NASA/TP-2010- 216136 

Desert Research and Technology Studies (DRATS) 2008: 

Evaluation of Small Pressurized Rover and Unpressurized 

Rover Prototype Vehicles in a Lunar Analog Environment 

Andrew F. J. Abercromby, Ph.D. 

Wyle Integrated Science and Engineering Group 

Johnson Space Center, Houston, Texas 

Michael L. Gernhardt, Ph.D. 

Johnson Space Center, Houston, Texas 

Harry Litaker 

Lockheed Martin 

Johnson Space Center, Houston, Texas 

November 2010 
 

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NASA/TP-2010- 216136 

Desert Research and Technology Studies (DRATS) 2008: 

Evaluation of Small Pressurized Rover and Unpressurized 

Rover Prototype Vehicles in a Lunar Analog Environment 

Andrew F. J. Abercromby, Ph.D. 

Wyle Integrated Science and Engineering Group 

Johnson Space Center, Houston, Texas 

Michael L. Gernhardt, Ph.D. 

Johnson Space Center, Houston, Texas 

Harry Litaker 

Lockheed Martin 

Johnson Space Center, Houston, Texas 

November 2010 
 

Available from: 

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Hanover, MD 21076-1320 Springfield, VA 22161 

301-621-0390 703-605-6000 

This report is also available in electronic form at http://techreports.larc.nasa.gov/cgi-bin/NTRS 
i 

CONTENTS 

1.0 INTRODUCTION ................................................................................................... 1 

1.1 Background and Significance ................................................................................. 2

1.2 Hypotheses and Test Objectives ............................................................................. 7 

2.0 METHODS ............................................................................................................... 8 

2.1 Protocol Design ....................................................................................................... 8 

2.1.1 One-Day UPR and SPR Traverses ....................................................................... 8 

2.1.2 Three-Day SPR Traverse ..................................................................................... 8 

2.1.3 Test of Contextual Geological Observations ...................................................... 8 

2.1.4 Nighttime Traverses ............................................................................................. 9 

2.1.5 Procedures, Mission Rules, and EVA Tools ........................................................ 10 

2.1.6 Traverse Planning and “Day-in-the-Life” Timeline Development ...................... 10 

2.1.7 Crews and Crew Training .................................................................................... 19 

2.2 Test Hardware ........................................................................................................... 19 

2.2.1 Unpressurized Rover / Mobility Chassis (aka “Chariot”) .................................... 19 

2.2.2 Small Pressurized Rover (SPR) ........................................................................... 21 

2.2.2.1 Suit Port Mockup .............................................................................................. 25 

2.2.2.2 Mockup MkIII Spacesuits and EVA Tools ....................................................... 28 

2.2.2.3 Communications, Networking and Navigation Infrastructure ........................... 31 

2.2.2.4 Mobile Mission Control Center ....................................................................... 32 

2.2.2.5 SPR Exercise Ergometer ................................................................................... 33 

2.2.3 Hardware Inspection ............................................................................................ 34 

2.3 Metrics and Hypotheses Testing ............................................................................ 34 

2.3.1 Hypothesis 1: Comparing Productivity and EVA Suit Time ................................ 35 

2.3.2 Hypothesis 2: Comparing Range ........................................................................... 37 
ii 

2.3.3 Hypothesis 3: Contextual Observations ............................................................... 38 

2.3.4 Hypothesis 4: Suit Port Human Factors ............................................................... 39 

2.3.5 Hypothesis 5: Human Factors during 3-Day Traverse ......................................... 39 

2.3.6 Other Test Objectives .......................................................................................... 43 

2.3.7 Subjective Crew Health Metrics .......................................................................... 44 

 3.0 RESULTS AND DISCUSSION ............................................................................ 46 

3.1 Hypothesis 1: Comparing Productivity and EVA Suit Time .................................. 46 

3.2 Hypothesis 2: Comparing Range ............................................................................ 47 

3.3 Hypothesis 3: Contextual Observations .................................................................. 48 

3.4 Hypothesis 4: Suit Port Human Factors .................................................................. 49 

3.5 Hypothesis 5: Human Factors during 3-day Traverse ............................................ 50 

3.5.1 Driving-Related Human Factors .......................................................................... 51 

3.5.2 Displays and Controls Human Factors ................................................................ 53 

3.5.3 Visibility Human Factors ..................................................................................... 55 

3.5.4 Suit Port Human Factors ...................................................................................... 58 

3.5.5 Habitability of Crew Accommodations ............................................................... 58 

3.5.6 SPR Exercise Device Human Factors ................................................................. 63 

3.6 Other Test Objectives ............................................................................................. 66 

3.6.1 Nighttime Driving and Exploration, Mapping, and 

Geological Sample Collection and Documentation Tasks .............................................. 66 

3.6.2 Measure Performance Metrics During 1-day 

and 3-day (SPR only) Exploration, Mapping, and Geological Traverses........................ 66 

4.0 CONCLUSIONS ..................................................................................................... 71 

5.0 REFERENCES ....................................................................................................... 72 

6.0 ACKNOWLEDGEMENTS .................................................................................... 72 

7.0 APPENDICES ........................................................................................................ 73 
iii 

TABLES 

Table 1 – UPR Timeline Assumptions. ....................................................................................... 12

Table 2 - SPR Timeline Assumptions. ......................................................................................... 13

Table 3 – Pavilion Lake Research Project Traverse Science Merit rating scale. ........................ 35

Table 4 – Science questions addressed by UPR and SPR traverses at Black Point Lava Flow .. 36

Table 5 – Pavilion Lake Research Project Data Quality Scale. ................................................... 37

Table 6 – Subjective Assessment of Contextual Observations scale. .......................................... 38

Table 7 – Bedford Thermal Comfort Scale.................................................................................. 44

Table 8 – Borg Rating of Perceived Exertion Scale. ................................................................... 45

Table 9 – Acceptability ratings for SPR driving during 3-day traverse. ..................................... 53

Table 10 – Acceptability ratings for SPR displays and controls during 3-day traverse. ............. 55

Table 11 – Acceptability ratings for SPR visibility during 3-day traverse. ................................. 56

Table 12 – Acceptability ratings for SPR habitability during daily operations during 3-day 

traverse. ........................................................................................................................................ 59

Table 13 – Acceptability ratings for SPR sleep stations and general habitat during 

3-day traverse. .............................................................................................................................. 60

Table 14 – Acceptability ratings for SPR cockpit during 3-day traverse. ................................... 61

Table 15 – Acceptability ratings for SPR exercise device. .......................................................... 64

Table 16 – SPR exercise device set-up and break down times. ................................................... 64

Table 17 – Performance metrics for UPR and SPR traverses at DRATS 2008. .......................... 67

Table 18 – Black Point Lava Flow Field Test: Science Traceability Matrix. .............................. 79

 
iv 

FIGURES 

Figure 1 – EVA estimates for LAT-2 Option 2 lunar architecture. .......................................... 2 

Figure 2 – Features of the Small Pressurized Rover (SPR) concept. ........................................ 4 

Figure 3 – Size comparison of Apollo Rover and SPR. ........................................................... 5 

Figure 4 – Overview of the stand-alone test site, 4 km south of base camp and 1 km north of 

Spider Ranch road. The test area included the prominent red sandstone outcrops and stopped 

upslope just shy of the exposed basaltic caprock. The SPR is seen at the far southeast corner 

of the test area, and the Humvee is parked at the northwest corner. ................................ 9

Figure 5 – Example of “Targets of Opportunity” from 2008 Pavilion Lake Research Project. 13

Figure 6 – Example of traverse plan format. ............................................................................ 15 

Figure 7 – Example of detailed “day-in-the-life” EVA timeline. ............................................ 16 

Figure 8 – Annotated map of Black Point Lava Flow showing tentative EVA stations. ........ 18 

Figure 9 – Chariot lunar mobility prototype vehicle. ............................................................... 20 

Figure 10 – Chariot vehicle in Unpressurized Rover configuration (with Mockup MkIII 

spacesuits).......................................................................................................................... 21 

Figure 11 – Interior photos of the SPR. Upper left, front cockpit showing redundant controls and 

touch-screen displays; upper right, view from front to rear; lower left, view from rear to 

front; and lower right, sleep station with privacy curtain partially deployed. ................... ... 22 

Figure 12 – Small Pressurized Rover cabin integrated with Chariot chassis ........................... ... 23 

Figure 13 – Integrating the SPR cabin with the Chariot chassis at the test site. ....................... ... 24 

Figure 14 – SPR interior cameras and microphones for human factors evaluations. ............... 25 

Figure 15 – Rear view of SPR showing mockup suits attached to suit ports. .......................... 26 

Figure 16 – A crewmember detaching from the SPR suit port. ................................................ 27 

Figure 17 – Mark III suit at Desert RATS 2006. ...................................................................... 29 

Figure 18 – Two Global Effects, Inc. MkIII Mockup Suits...................................................... 30 

Figure 19 - Lunar communications architecture modeled at D-RATS 2008. ........................... 31 

Figure 20 – Mobile Mission Control Center (MMCC). ............................................................ 33 

Figure 21 – SPR exercise ergometer. ........................................................................................ 34 

Figure 22 – Cooper-Harper rating for vehicle handling qualities. ............................................ 41 

Figure 23 – Modified Cooper-Harper rating of operator compensation. .................................. 42

Figure 24 – Corlett and Bishop Discomfort Scale (Corlett & Bishop, 1976). .......................... 45

Figure 25 - UPR vs. SPR: Total EVA suit time (average per crewmember). 46 

Figure 26 - UPR vs. SPR: Performance (Scientific Productivity Index). 46

Figure 27 - UPR vs. SPR: Performance per EVA hour. ........................................................... 46 
v 

Figure 28 - UPR vs. SPR: Traverse Distance and Range. ........................................................ 47 

Figure 29 - Field geologist ratings of SPR contextual geological observations. ...................... 48 

Figure 30 – Acceptability ratings for 13 aspects of SPR suit ports. ......................................... 49 

Figure 31 – Cooper-Harper ratings for driving the SPR during the 3-day mission; the size of the 

dot represents the number of scores at that rating (scale on top right). From Litaker et al, 

2008. .................................................................................................................................. 52 

Figure 32 – Modified Cooper-Harper ratings for the displays and controls interface .............. 54 

Figure 33- Geologist using lower bubble to photograph a geologic item of interest (left). The 

SPR’s panoramic front window enhanced driving and scientific observations (right). .... 57 

Figure 34 – Night operations using the interior and exterior lighting of the SPR. ................... 57 

Figure 35 – Two CTB stowage areas: under the bench (left, shown as the bench is raised behind 

a cockpit seat) and under the floor (right). ........................................................................ 59

Figure 36 – Subjective fatigue ratings at the beginning (Pre) and end (Post) of 

of each of the 3-day traverse ..................................................................................................... 62 

Figure 37 – Participant demonstrating the SPR exercise device during simulated aerobic cycling 

and resistive exercise. ........................................................................................................ 65 

Figure 38 – Concept drawing of resistive upper body exercise with a bar and pulley system. 65

Figure 39- Nighttime EVA performed by one geologist with support from inside SPR. 66 

Figure 40 - Comparison of crew time breakdown for 1-day UPR and SPR traverses............. 68 

Figure 41 – Path of the SPR during the 3-day traverse (red: day 1, green: day 2, yellow: day 3). 

 ........................................................................................................................................... 68 

Figure 42 - SPR Egress and Ingress Durations. ........................................................................ 70 

Figure 43 – Desert-RATS 2008 Team (many other team-members not shown). ..................... 73 

Figure 44 – View of lava flow escarpment ~4 km (2.5 miles) from proposed base camp location. 

 ............................................................................................................................................. 74 

Figure 45 – Examples of geological sites of interest at Black Point Lava Flow. ..................... 75 

Figure 46 – Test Site: Black Point Lava Flow, Arizona. .......................................................... 76 

Figure 47 – Test site base camp location. ................................................................................. 77

Figure 48 – Looking south along the edge of Black Point Lava Flow; note varying slopes, varied 

geology, and representative vegetation. .................................................................................... 78 

Figure 49 – Example of slope variation, geological features and moderate vegetation at edge of 

Black Point Lava Flow.............................................................................................................. 78

Figure D1: The Black Point Lava Flow and its surroundings; the circle is 10 km in diameter and 

centered on the location of base camp, at the western edge of this 2.4 MY basalt flow. ......... 99 

Figure D2: Detailed view of Black Point Lava Flow and photogeologic map produced by the 

Science Team; the actual basalt flow is not explicitly mapped in this rendition, but other volcanic 
vi 

features are (in red), suggestive of additional volcanic events. The detailed mapping concentrated 

on more subdued morphologies, suggesting different rock types. The traverses concentrated on 

the Western edge of the flow and the adjacent units (brown ) to the West, as well as on the 

additional (red) volcanic formations. ........................................................................................ 100 

Figure D3 - 1 Day UPR and SPR traverses; note the addition of Station 3 for SPR over that of 

UPR. Initially, the SPR traverse was laid out along the green line, which however was not doable 

because of too many fences; the red line suggests the fastest way back to base camp, in case of 

unforeseen delays. The actual traverse followed the yellow line with the exception of Station 2, 

where the green line was followed. This traverse constituted Day 1 of the long duration (3days/2 

nights/56 km total travel) tests, yet SPR back tracked S (rather than towards base camp) from 

Station 5 for an overnight stop close to the blue spot (see Fig. 4). ........................................... 101 

Figure D4 - Traverses of Day 2 and Day 3 for the long duration (3 days/2 nights/covering 56 

km) SPR tests; overnight camps are depicted in pink as night 1 (N1) and night 2 (N2). ......... 102 
vii 

ACRONYMS 

CxAT_Lunar Constellation Lunar Architecture Team 

DRATS Desert Research and Technology Studies 

EVA Extra Vehicular Activity 

HMP Haughton-Mars Project 

LAT Lunar Architecture Team 

LER Lunar Electric Rover 

PLSS Primary Life Support System 

ECLSS Environmental Control/Life Support System 

SPR Small Pressurized Rover 

UPR Unpressurized Rover 

USGS United States Geological Survey 

 
viii 

ABSTRACT 

A system of two or more Small Pressurized Rovers (SPRs), also referred to as Lunar Electric 

Rovers (LERs), is an integral part of NASA’s plans for returning humans to the moon. In the 

SPR concept, each vehicle includes a small pressurized cabin to safely sustain two crewmembers 

on the surface for 14 to 28 days. Through suit ports, crewmembers may rapidly egress and 

ingress the cabin for extravehicular activities (EVAs). In addition to achieving a surface 

exploration range that is potentially orders of magnitude greater than what was achievable during 

the Apollo Program, the SPR concept offers many other benefits, particularly with respect to the 

health, safety, and productivity of crewmembers. 

The primary purpose of the Desert Research and Technology Studies (DRATS) 2008 field test, 

conducted at the Black Point Lava Flow in Arizona, was to objectively and quantitatively 

compare the scientific productivity and human factors during 1-day exploration, mapping, and 

geological traverses performed using Small Pressurized Rover (SPR) and Unpressurized Rover 

(UPR) prototype vehicles. The habitability, human factors, and performance characteristics of 

the SPR vehicle and crew were also recorded throughout a high-fidelity 3-day lunar traverse 

simulation. Before the field test began, a detailed test protocol and flight plan were developed 

including hypotheses, metrics, and prospectively defined levels of practical significance to be 

used in the testing of all hypotheses. 

Quantitative assessment of crew productivity by an on-site team of expert field geologists found 

that compared with UPR traverses, the same crewmembers were 57% more productive during 

SPR traverses and used 61% less EVA time. The study also indicated that the SPR increased 

comfort and decreased fatigue over the UPR. The habitability and human factors of the SPR 

throughout the 3-day traverses was acceptable according to the prospectively defined human 

factors metrics and acceptability criteria, although suggested modifications to several vehicle 

subsystems were identified in the assessment.
1 

1.0 INTRODUCTION

The Small Pressurized Rover (SPR), also known as the Lunar Electric Rover (LER), is an 

integral part of the lunar surface architectures that are under consideration by NASA. The SPR is 

expected to offer numerous health and safety advantages that will accrue from having a 

pressurized safe haven and radiation shelter in close proximity to the crew at all times during 

lunar surface operations. The SPR combines a comfortable shirtsleeve, sensor-augmented 

environment for gross translations and geological and mapping observations with the ability to 

rapidly place suited astronauts on the planetary surface using suit ports, to take full advantage of 

the unique human perception, judgment, and dexterity. This combination of features is expected 

to increase the productivity of crew extravehicular activity (EVA) time and provide significantly 

greater exploration ranges than an Unpressurized Rover (UPR). 

To objectively evaluate the potential benefits of the SPR compared with a UPR, Earth-based 

functional versions of the UPR and SPR vehicles were designed and fabricated to support this 

study. The primary objectives of the study were to 1) evaluate the productivity of the SPR 

compared to a UPR on 1-day geological and mapping traverses and 2) evaluate the human 

factors and crew accommodations of the SPR and suit ports on 1- and 3-day science, exploration, 

and mapping traverses. Other objectives included evaluation of single-person EVA capability 

and assessment of nighttime operations of the SPR and UPR. 

The primary objectives of this study were decomposed into specific hypotheses, which were 

tested with a combination of objective and subjective productivity, performance, and human 

factors metrics, which are detailed in Section 2.3. The study design incorporated a direct crossover comparison between the SPR and the UPR, using two different crews, each made up of a 

professional field geologist and an active NASA astronaut with EVA experience. Because the 

number of subjects was limited, use of inferential statistics was not warranted. However, 

descriptive statistics were combined with prospectively defined levels of practical significance to 

test each hypothesis. As an example, the various human factors ratings are based on a 10-point 

scale, composed of five distinct categories that range from totally unacceptable to totally 

acceptable, and a categorical difference was considered practically significant. These metrics, 

procedures, and data collection methods will also be applicable to future science and engineering 

evaluations. 

In this study the SPR was operated in a manner consistent with the SPR functional requirements 

in the Preliminary Report of the Small Pressurized Rover (IHMC, 2008). Detailed procedures 

and flight rules were developed to control the SPR operations within these constraints. The 

human factors and mechanisms of the suit ports to be used in this study were kinematically 

accurate and consistent with a fully pressurized engineering model of the suit port. The mockup 

suit port enabled quantitative evaluation of 12 different aspects of the preliminary suit port 

design related to suit donning and doffing and suit docking and undocking to and from the suit 

port. However, the Earth-based functional SPR and the lightweight EVA suits were not 

pressurized. Because of this limitation, the suit human factors in this study should not be 

considered representative of flight-like conditions. 

In the Lunar Architecture Team (LAT) studies (Humphries, 2006), detailed EVA analysis and 

timelines were generated for a wide range of construction tasks across the six options evaluated, 

as well as for four representative science tasks that ranged from geological exploration to a 

variety of small and large instrument package deployments and assembly operations. The 
exploration, mapping, and geolog

tasks for the SPR because of a co

reason a geological, exploration,

comparing the SPR with a UPR. 

engineering evaluations of the SP

Yard” facility. 

1.1 BACKGROUND AND SIGN

Fewer than 20 lunar extravehicula

Program. Architectures considere

(CxAT_Lunar), which followed t

exploration EVA time. As Figure

EVA hours in an extreme and cha

performed more than 3 lunar EVA

performing as many as 76 lunar E

and considerable dust contaminat

trauma (e.g. finger nail delaminat

current EVA suits often occurs du

consequences of a significant sola

exploration to potentially hundred

decompression sickness risk and 

cabin pressure compared to Apoll

Figure 1 – EVA estimates for LAT-2 O

2 

logical tasks represented both high-frequency and 

 combination of terrain, range, and observational d

and mapping traverse was selected for the initia

. Additional construction and science tasks and o

 SPR are planned to take place in the Johnson Spac

GNIFICANCE

ular activities (EVAs) were performed during the 

ered by NASA’s Constellation Lunar Architecture

d the LAT studies, could involve as many as 30,00

ure 1 demonstrates, these plans represent an enorm

challenging environment. No previous astronaut or

VAs, yet future astronauts and their EVA suits mu

r EVAs during a 6-month mission. Damage to suit

nation occurred during Apollo after only three EVA

nation, contusions, lacerations, shoulder injuries) o

 during a single EVA. Other challenges include th

olar particle event, galactic cosmic rays, the need 

reds of kilometers from an outpost, and the increas

d prebreathe requirements associated with 55 kPa

ollo’s 34.5 kPa (5 psi)/100% O2. 

2 Option 2 lunar architecture.

d demanding 

l demands. For this 

tial evaluation 

d other 

pace Center “Rock 

he entire Apollo 

re Team

,000 hours of lunar 

rmous increase in 

t or spacesuit has 

must be capable of 

uit components 

VAs; suit-induced 

of astronauts in 

 the risk and 

d to extend 

eased 

Pa (8 psi)/32% O2
3 

A novel approach to optimizing human safety and performance during planetary surface 

exploration is currently being considered by NASA. The heart of the concept is a system of two 

Small Pressurized Rovers (SPRs), each of which nominally accommodates two astronauts in a 

shirtsleeve environment as they explore the planetary surface. 

The SPRs (Figure 2) are intended to optimize human safety and performance in planetary 

exploration by combining a comfortable shirtsleeve, sensor-augmented environment for gross 

translations and geological observations with the ability to rapidly place suited astronauts on the 

planetary surface to take full advantage of human perception, judgment, and dexterity. As 

illustrated in Figure 2, each SPR is slightly larger than the unpressurized Apollo rover. The front 

cabin of the rover provides a pressurized shirtsleeve environment at the same pressure as the 

habitat or lander. Each SPR incorporates two suit ports, enabling both rapid egress to the 

planetary surface and rapid ingress to the shelter of the rover in response to solar particle events, 

suit malfunctions, or medical emergencies. A side hatch that mates with the habitat, lander, or 

other SPRs enables transfer of personnel and equipment under pressure. This capability, along 

with the capability to quickly step into the suits and perform surface operations, results in

crewmembers “going EVA” for only the limited portions of an EVA sortie that require the 

superior perception, judgment, and dexterity of an astronaut in an EVA suit. It may also enable 

single-person EVA operations wherein one crewmember performs boots-on-surface EVA tasks 

with in situ intravehicular activity (IVA) support from a second crewmember that remains inside 

the SPR. The SPRs also incorporate an EVA driving station, and therefore can be operated with 

all the advantages of a UPR. 
Figure 2 – Featu

4 

atures of the Small Pressurized Rover (SPR) concept. 
 

 Figure 3 – Size compa

5 

parison of Apollo Rover and SPR.
6 

Because the SPRs are capable of multi-day or week-long sortie durations rather than the rangelimited (8-hour) EVA activities achievable with a UPR, the overhead of returning to the outpost 

or lander at the end of each day will be avoided, and exploration range may be significantly 

greater than with UPRs. Furthermore, because each SPR is a backup to the other, and capable of 

supporting four crewmembers in a contingency return to the base or lander, the system of two 

SPRs provides greater range capability than a single larger pressurized rover. It is hypothesized 

that using SPR vehicles with this combination of features and capabilities will increase the safety 

and productivity of suited crew during exploration, mapping, and geological operations 

compared with using UPR vehicles. 

The SPRs are a central element in the lunar architectures currently being developed and 

evaluated by NASA. For this reason there is an immediate need to verify the feasibility and 

operational characteristics of the SPR concept and to refine mass, volume, dimension, range, 

consumables usage, and cost estimates not only for the SPRs but also for the EVA suits and other 

vehicles and systems with which the SPRs will interact. Estimates of performance metrics - such 

as drive time, distance driven, range achieved, stationary time, and EVA time and EVA 

frequency during exploration, mapping, and geological traverses - are necessary inputs to models 

of surface mobility power and energy storage used by NASA’s Lunar Surface Systems Project. 

EVA frequency and duration estimates are also sought by the Human Research Program for use 

in models of physiological adaptations during long-duration lunar missions. Quantifying the 

extent to which SPRs improve crew safety and productivity during lunar exploration over safety 

and productivity with UPR-based exploration is necessary to inform future lunar surface system 

architectural decisions. 

Performing a comprehensive comparison of the SPR concept with a UPR alternative would 

require that each vehicle be evaluated and compared under the full range of nominal and 

contingency operational scenarios in which it might be used on the lunar surface, for example, 

payload offloading, pressurized or unpressurized payload transportation, payload deployment, 

crew transportation, solar particle event, incapacitated crewmember, incapacitated vehicle, 

scouting, scientific exploration, scientific instrument deployment, berm building, and terrain 

clearing and leveling. However, flight-by-flight development of detailed EVA timelines during 

the Lunar Architecture Team Phase 2 (LAT-2) Project indicated that more than 90% of total 

EVA time would be spent on science and exploration activities over a 10-year lunar surface 

program. Thus, the purpose of this study was to evaluate the human factors, performance, and 

productivity of the SPR concept in an operational environment and to quantify and compare the 

performance and productivity achieved during exploration, mapping, and geological traverses 

performed using UPR and SPR vehicles. 

Baseline evaluation and comparison of the UPR and SPR vehicles was accomplished by 

planning and executing two 1-day exploration, mapping, and geological traverses with each 

vehicle on the Black Point Lava Flow near Flagstaff, Arizona (see Appendix A). Productivity, 

human factors, and performance metrics were also measured during a single 3-day SPR 

exploration, mapping, and geological traverse and during short (≤ 3 hours) nighttime UPR and 

SPR traverses. A single-person EVA operation concept with in situ IVA support from inside the 

SPR was also evaluated. The study design and metrics used to quantify productivity, human 

factors, and performance during all traverses are detailed in Section 2.0. 
7 

1.2 HYPOTHESES AND TEST OBJECTIVES

The hypotheses and engineering objectives for this study are detailed below. The statistical 

analysis and the specific metrics associated with each hypothesis are detailed in Section 2.3. 

Hypotheses: 

1) Productivity achieved during 1-day exploration, mapping, and geological traverses using 

the Small Pressurized Rover (SPR) will be equal to or greater than the productivity 

achieved during Unpressurized Rover (UPR) traverses, with less EVA suit time. 

2) The range achieved during 1-day exploration, mapping, and geological traverses in the 

SPR will be greater than during 1-day UPR traverses. 

3) Subjective assessment of contextual observations from inside an SPR will be equal to 

assessment of contextual observations from inside an EVA suit. 

4) Human interfaces with the SPR suit ports and alignment guides will be acceptable as 

assessed by human factors metrics. 

5) The human factors and crew accommodations within the SPR will be acceptable to 

support a 3-day exploration, mapping, and geological traverse. 

Other Test Objectives: 

6) Perform nighttime driving and exploration, mapping, and geological sample collection 

and documentation tasks using SPR and UPR vehicles. 

7) Measure performance metrics during 1-day and 3-day (SPR only) exploration, mapping, 

and geological traverses. 
8 

2.0 METHODS

The primary hypotheses (Section 1.2) were tested by planning and performing a series of 1-day 

and 3-day exploration, mapping, and geological traverses at the Black Point Lava Flow test site, 

during which productivity, human factors, and performance metrics, as well as other engineering 

data, were collected. The rationale for the use of the Black Point Lava Flow test site is described 

in Appendix A. 

Preliminary data reduction and analysis began during the field test to enable verification of data 

quality. Comprehensive reduction and analysis of data were completed after the field test 

concluded, and each study hypothesis was tested as described in Section 2.3. 

2.1 PROTOCOL DESIGN

2.1.1 ONE-DAY UPR AND SPR TRAVERSES

During the first of 2 weeks of testing at the Black Point Lava Flow test site, a series of four 

predefined 1-day exploration, mapping, and geological traverses were performed. During the 

pretest planning phase of the study, the Traverse Planning Team used photogeologic data to 

develop a detailed 1-day traverse plan designed to optimize scientific productivity based on 

clearly defined science objectives and the constraints and capabilities of the UPR. The same 

Traverse Planning Team also planned a 1-day traverse to optimize scientific productivity based 

on the same scientific objectives but the different constraints and capabilities of the SPR. The 

traverse planning and timeline development process is described in greater detail in Section 

2.1.6. 

Two crews of two people performed each of the planned 1-day traverses so that a total of two 

1-day UPR traverses and two 1-day SPR traverses were performed; that is, each two-person crew 

performed a traverse in each vehicle. The productivity, performance, and human factors of the 

subjects and vehicles during all traverses were measured and compared. 

2.1.2 THREE-DAY SPR TRAVERSE

In addition to the 1-day UPR and SPR traverses, the Traverse Planning Team planned – and 

detailed timelines were developed for – a 3-day SPR traverse that was performed during the 

second week of field testing. Because of time constraints the 3-day SPR traverse was performed 

by only one of the two-person crews. The same metrics were collected during the 3-day SPR 

traverse as during the 1-day traverses, with the purpose of evaluating the productivity, human 

factors, and performance in a way that was comparable with 1-day traverses. Furthermore, the 

3-day traverse allowed investigators to assess the acceptability of the SPR human factors and 

crew accommodations for supporting 3-day traverses. 

2.1.3 TEST OF CONTEXTUAL GEOLOGICAL OBSERVATIONS 

A stand-alone protocol was developed to evaluate the hypothesis that subjective assessment of 

contextual observations made from inside an SPR will be equal to assessment of contextual 

observations made from inside an EVA suit. Members of the DRATS Science Team, all trained 

geologists, investigated a relatively small test site on foot and subsequently from inside the SPR. 

The objective was to compare the observational capabilities and constraints of the SPR cabin 
9 

with the capabilities of an astronaut walking during an EVA. Because of practical constraints, 

the geologists did not wear the mockup suits, so the actual comparison performed was between 

the SPR and the “shirtsleeve” environment. 

The test site was about 200 × 300 m in size and contained typical geologic features of the general 

area: it was placed on a gradually steepening slope that was characterized – close to the bottom –

by an outcrop of red Moenkopi formation and capped – in mesa-type fashion – by the Black 

Point Lava Flow. Figure 4 illustrates typical scenes of the test area. 

Figure 4 – Overview of the stand-alone test site, 4 km south of base camp and 1 km north of Spider Ranch 

road. The test area included the prominent red sandstone outcrops and stopped upslope just shy of the 

exposed basaltic caprock. The SPR is seen at the far southeast corner of the test area, and the Humvee is 

parked at the northwest corner. 

Each of the three geologists first walked the entire test area for exactly 20 minutes and used a 

dictaphone to record verbal descriptions. No sampling tools were carried into the field and no 

rocks were collected, consistent with the objective of the test, which focused on observational 

capabilities only. Subsequently, each geologist spent up to 20 minutes inside the SPR, occupying 

the right-hand seat and the observation bubble, if so desired. The driver followed the geologist’s 

instructions on where to go and how to position the SPR windows. During the SPR portion of the 

protocol, geologists were instructed to make observations for 20 minutes. At the end of the 20 

minutes inside the SPR, the geologists were asked to rate the quality of the contextual 

observations that could be made from inside the SPR using an index defined in Section 2.3.3. 

Written evaluations by each individual geologist were generated at the end of the test. 

2.1.4 NIGHTTIME TRAVERSES

The ability to drive lunar rovers and perform EVA during darkness will be required during future 

lunar missions, during lunar night cycles and/or when it is necessary to operate in shadowed 

regions. Indeed, many sites of geological interest are situated in permanently shadowed regions 

of the Moon. 

Nighttime UPR operations (with crew remaining on board the vehicle) were performed during 

the Human Robotic Systems (HRS) field test near Moses Lake, Washington, in June 2008 

(Humphries, K., 2008). Lessons learned about navigation, lighting, and display colors and 

brightness during that exercise led to design modifications, which were tested during the 

performance of a short-duration (1-hour) nighttime traverse using the SPR vehicle. The traverse 
10 

involved vehicle driving, IVA contextual observations, and EVA geological sample collection 

tasks (rock sample, soil sample, trench sample, photodocumentation). Human factors and 

performance metrics were collected during these tasks with the purpose of identifying any 

inadequacies with system designs or procedures. 

2.1.5 PROCEDURES, MISSION RULES, AND EVA TOOLS

A controlled and meaningful evaluation and comparison of the UPR and SPR, as well as safety 

of subjects and protection of equipment, required consistency in the way that different tasks were 

performed by all subjects. UPR and EVA mission rules and procedures, including geological 

sampling procedures, were developed and successfully used during Apollo. However, future 

lunar missions will use different vehicles, tools, and instruments; will involve larger crews; and 

may define different levels of acceptable risk. Indeed, no one has had previous experience 

operating pressurized rovers during lunar exploration. 

Taking Apollo and comparable Shuttle and ISS procedures as a starting point, procedures and 

mission rules were developed, tested, and revised for UPR- and SPR-based EVA operations. 

Apollo-era EVA procedures for collecting geological samples (rock samples, soil samples, 

trenching samples, drive tube samples) were modified, documented, and used during the HRS 

Moses Lake field test. Apollo-style EVA tools were also used during sampling tasks. Putting 

into practice the lessons learned during Moses Lake testing (that is, excessive time spent on 

photodocumentation, inefficient use of the second EVA crewmember during sampling tasks, and 

inadequate information available to science CAPCOM/backroom), procedures were modified 

and EVA tools and camera equipment were developed and tested at field test on Devon Island, in 

the Canadian High Arctic, in August 2008. The Haughton-Mars Project (HMP) (Lee, P., 2009) 

test was also the first opportunity to test many mission rules and procedures not tested during the 

Moses Lake field test, such as “Targets of Opportunity”, SPR checkout, SPR power-up, Suit 

PLSS/Suit Port checkout, Suit Port egress, and Suit Port ingress. Lessons learned during the 

HMP field test were then used to further refine procedures, mission rules, and EVA tools before 

testing at Black Point Lava Flow. 

2.1.6 TRAVERSE PLANNING AND “DAY-IN-THE-LIFE” TIMELINE DEVELOPMENT

Traverse plans and detailed timelines were developed that were consistent with defined 

capabilities, constraints, and assumptions. The assumptions used when developing timelines for 

UPR and SPR traverses are listed in Table 1 and Table 2, respectively. The functional 

requirements of the SPR, as described in the Preliminary Report of the Small Pressurized Rover 

(IHMC, 2008), are described below: 

Small Pressurized Rover Functional Requirements 

• Contingency return capability always available 

• Nominal 2-person crew per SPR, 4-person crew in contingency

• Power-up and check-out include suit and Portable Life Support System (PLSS) power-up and 

check-out: ≤ 1 hour

• Dock with or undock from habitat or lander: 
11 

o ≤ 10 minutes 

o ≤ 0.03 kg gas loss 

o Capable of several (TBD) dock/undock cycles per day

o Robust to dust contamination

• Nominal velocity: 10 kilometers per hour

• Driving naked-eye visibility should be comparable to walking in an EVA suit; that is, eyes at 

the same level, and a similar field of view.

o Augmented by multi-spectral cameras and instruments

• Visual accessibility to geological targets comparable to EVA observations; that is, naked 

eyes ≤ 1 m of targets

o Possibility of magnification optics providing superior capability over EVA 

observations

• Suit donning and ingress or egress

o ≤ 10 minutes

o ≤ 0.03 kg gas losses per person

o Capable of several (TBD) dock/undock cycles per day

o ≥ 2 independent methods of ingress and egress

o Robust to dust contamination

• Vehicle mass (excluding mobility chassis): ≤ 2400 kg

• Habitable volume: ~10 m3

• 12 two-person EVA hours at 200-km range on batteries and nominal consumable load

• Ability to augment power and consumables range and duration to achieve ≥ 1000 km 

• PLSS recharge time ≤ 30 minutes

• Crewmembers ≤ 20 minutes from ice-shielded lock radiation protection (including translation 

to SPRs and ingress)

• Heat and humidity rejection provided by airflow through ice-shielded lock and condensing 

heat exchanger 
12 

Table 1 – UPR Timeline Assumptions. 
13 

Table 2 – SPR Timeline Assumptions. 

The Desert RATS Science Team identified and prioritized specific sites of scientific interest in 

the test site region, using remote sensing data. The resolution of remote sensing data used was 

equivalent to that which is expected to be used before a crewed lunar mission that has not been 

preceded by robotic or crewed missions to that site. A traverse plan was then developed for a 

1-day UPR traverse based on the assumptions, constraints, and capabilities associated with that 

vehicle. The process was repeated for the SPR vehicle. The Science Team planned traverses 

with the objective of maximizing productivity with each vehicle. Traverse paths for UPR and 

SPR 1-day traverses were expected to differ because of the differing capabilities of the vehicles. 

A 3-day SPR traverse plan was also developed by the science team based on the same set of 

predefined prioritized science sites and objectives. 

Traverse plans included detailed timelines and EVA stations, each with specific tasks associated 

with the science objectives at those stations. Also included in traverse plans were “get-ahead” 

tasks, which were secondary tasks that would be accomplished if the nominal tasks were 

completed and the subjects were ahead of the timeline by a predefined amount of time. 

Figure 5 – Example of “Targets of Opportunity” from 2008 Pavilion Lake Research Project. 

Targets of 

Opportunity

Max Duration 

of Stay

GPS 

Fix

Video 

Priorities

Observations to 

Record Collection Deploy Marker

Groundwater 20 min Yes Context

Extent of flow. 

Assoc . fauna. 

Assoc . microbialites.

N/A Yes

Datable Structure 20 min 

If collec t - 30 min Yes Context Morphology of microbialites if > 35 m No

Microbial Mats 20 min 

If collec t - 30 min Yes Context Zoom

Extent, thickness. 

Color. 

Surface texture.

if > 35 m No

Unusual 

Morphology 10 min Yes 360 around structure

Gross morphology. 

Surface roughness. 

Mound relationships.

No No
14 

In addition to the nominal and “get-ahead” tasks, the Science Team developed a list of prioritized 

“Targets of Opportunity”, which were defined as features of scientific interest that might be 

observed during a traverse but were not stated as traverse objectives in the detailed traverse plan. 

Mission rules were documented that defined the appropriate course of action when Targets of 

Opportunity were identified, based on the value of the Targets of Opportunity, the remaining 

traverse objectives, and the time remaining. 

Figure 5 is an example of a traverse plan from the Pavilion Lake Research Project (nominal tasks 

and get-ahead tasks not shown). This format was modified to include specific nominal and getahead science objectives at each station. For each vehicle, the detailed timeline for the entire 

traverse day was also developed consistent with the current surface operations assumptions of 

the Lunar Surface Systems Project and with guidance from the Johnson Space Center (JSC) 

Mission Operations Directorate. Examples of a traverse plan and a “day-in-the-life” EVA 

timeline are shown in Figure 6 and Figure 7, respectively. 
15 

Figure 6 – Example of traverse plan format. 
16 

Figure 7 – Example of detailed “day-in-the-life” EVA timeline. 
17 

An annotated map of the Black Point Lava Flow test site is shown in Figure 8, and a brief 

overview of the geology of Black Point Lava Flow is included in the Science Team’s report in 

Appendix D. The team developed the Science Traceability Matrix, which includes prioritized 

science stations and targets of opportunity, and is included in Appendix B. The matrix was 

derived from preliminary interpretation of a U.S. Geological Survey (USGS) aerial photomosaic 

of the test area. Using this preliminary interpretation, the Science Team identified the following 

geologic units and associated objectives: 

Geologic Units 

• Volcanics 

o Black Point Lava Flow or “The Flow” 

o Lava flows – undifferentiated 

o Cinder cones 

o Dissected layered unit and lava flow cap rock 

• Undetermined (sedimentary? igneous?) 

o Marbled terrain north of flow (includes marbled albedo unit, dissected unit, 

nondissected transitional unit, and “knobby” unit) 

o Marbled terrain south of flow 

o Layered terrain northeast of (“below”) scarp 

o More layered terrain – undifferentiated 

o Layered topographic highs 

o Chaotic terrain 

o Dissected layered unit and valley 

• Other 

o High-albedo units 

o Fluvial channel 

Overarching Scientific Objectives

1) Determine the origin and the nature of the geologic units represented at the site. 

2) Understand age relationships and reconstruct the geologic evolution of the site. 

Specific Scientific Objectives

1) Understand the geology of the Black Point Lava Flow (BPLF), in particular its 

morphology, structure, petrology, mineralogy, chemistry, age, and any spatial and 

temporal variations of these characteristics. 

2) Understand the geology of other lava flows and volcanic features in the area and their 

relation to the BPLF in space and time. 

3) Understand the origin and nature of other geologic units and features in the area and their 

relation to the BPLF in space and time. 
18 

Figure 8 – Annotated map of Black Point Lava Flow showing tentative EVA stations.
19 

2.1.7 CREWS AND CREW TRAINING

Before deployment into the field, four test subjects (“crewmembers”) were identified. Each twoperson crew included one astronaut with EVA experience and one field geologist. Subjects were 

briefed on the objectives and methods of the study and participated in a pretest training program 

that included review and practice of the following: 

- Study hypotheses and objectives 

- Metrics and data collection procedures 

- Mission rules 

- SPR procedures 

- UPR procedures 

- Mockup Mark III spacesuit fit check and familiarization 

- Suit port ingress and egress procedures 

- UPR driving 

- SPR driving 

- EVA geological sampling tasks 

- Geological briefings 

- Communications protocols 

Upon deployment to the field test site, all subjects completed a brief refresher course. The 

combination of pretest training and the refresher course ensured the safety of the subjects and 

protection of the equipment, and minimized potential confounding of results because of timevarying crewmember learning effects. 

2.2 TEST HARDWARE 

2.2.1 UNPRESSURIZED ROVER / MOBILITY CHASSIS (AKA “CHARIOT”) 

A prototype of a lunar vehicle, known as Chariot,(Figure 9) was used throughout this test, first as 

an Unpressurized Rover (UPR) and then as the mobility base of the SPR. The Chariot is a new 

multipurpose, reconfigurable, modular lunar surface vehicle. The basic vehicle consists of a 

“mobility base”; that is, a chassis, wheel modules, electronics, and batteries. It is capable of 

multiple modes of operation: human direct control from on board, teleoperation with small time 

delays from a habitation module or lander, and supervision under longer time delays from Earth. 

With the right attachments and/or crew accommodations, the Chariot configuration will be able 

to serve a large number of functions on the lunar surface. Functions may include serving as a 

cargo carrier, regolith mover, and cable layer, and as human transportation. 

Among the most important features of the Chariot chassis are the combination passive and active 

suspension and the crab steering. The suspension can lower the vehicle for easy mounting by the 
20 

crew, then raise it to a height that provides optimum clearance but would otherwise be 

undesirable for crew accessibility. An active suspension provides the ability to dynamically 

level the body when the vehicle is traversing a slope, avoiding the feeling that one is about to fall 

out of the vehicle, which the Apollo crew had noted. Redundancy in wheel modules is enhanced 

through active suspension. If the steering, brake, or drive of a wheel module fails, that wheel can 

be lifted off the surface and the vehicle will go home on five wheels. This is not possible with a 

four-wheeled configuration. Crab steering means each of the six wheels can rotate 360 degrees, 

giving the vehicle the ability to move in any direction or rotate at any point. This makes 

maneuvering possible in tight places where a conventionally steered vehicle could not operate. 

Figure 9 – Chariot lunar mobility prototype vehicle. 

During testing, Chariot was first used in the UPR configuration (Figure 10), in which two suit 

attachment and support structures, or “turrets,” were attached to the chassis. The turrets are 

based on the Mark III (MkIII) EVA suit donning stand and allow users to dock the waist ring of 

the suit to the structure and thereby secure the suit in place and unload the weight of the suit 

from the crewmember. Each turret also incorporates a vehicle control interface, enabling either 

crewmember to control the vehicle and also allowing the turrets to be rotated through 360°. 

After all UPR test conditions were completed, the turrets were removed and the SPR cabin was 

integrated onto the Chariot vehicle (see Section 2.2.2). Differential GPS data were collected 

from the Chariot during all test conditions. 
21 

Figure 10 – Chariot vehicle in Unpressurized Rover configuration (with Mockup MkIII spacesuits). 

2.2.2 SMALL PRESSURIZED ROVER (SPR) 

The SPR cabin used in this study was developed as a collaborative effort between JSC, Langley 

Research Center, Ames Research Center, and Glenn Research Center. The cabin was not 

pressurized but incorporated functional suit ports including alignment guides and clamping 

mechanisms, included all necessary crew accommodations to support a traverse of 3+ days, and 

was fully integrated with the Chariot chassis (Figure 12 and Figure 13) consistent with NASA’s 

current lunar architecture assumptions. Rigorous testing of the integrated Chariot-SPR was 

performed at the JSC “Rock Yard” facility before it was deployed to the field. 

For living accommodations, the SPR had two sleep stations with privacy curtains, a functional 

hot and cold water dispenser and waste containment system (WCS), functional floor and cabin 

stowage areas, and seven Crew Transport Bags (CTBs) filled with a variety of food, equipment, 

and other consumables. 
22 

 

 

Figure 11 – Interior photos of the SPR. Upper left, front cockpit showing redundant controls and touchscreen displays; upper right, view from front to rear; lower left, view from rear to front; and lower right, 

sleep station with privacy curtain partially deployed.

Six small cameras and one wide-angle dome camera were positioned throughout the SPR to 

record the internal interactions between the humans and the machine’s habitable volume and 

systems (Figure 14). Of these six cameras, four small cameras were located in the front cockpit 

area of the vehicle – one focused on the participants while they were in the front seats, another 

focused outside the left front window panel to record the terrain, and the final two focused on 

both the starboard and port suit ports. The remaining two small cameras were mounted in the 

rear over each suit port and were focused forward to record such things as hand placement when 

participants entered the suit port and crew interaction inside the cabin (for example, meal 

preparation and sleep station setup). The wide-angle dome camera was placed aft of the vehicle 

center as a backup camera. This camera had a view of the entire vehicle from the port side hatch 

to the front windows. In addition, an array microphone was positioned in the front of the vehicle 

above the cockpit as a dual source of wireless radio communications and audio recording. 

Recording was accomplished by two digital video recorders (DVR) and a sound mixer 

positioned under the floor of the vehicle. 
23 

Figure 12 – Small Pressurized Rover cabin integrated with Chariot chassis. 
24 

Figure 13 – Integrating the SPR cabin with the Chariot chassis at the test site. 
Figure 14 – SPR interio

2.2.2.1 Suit Port Mockup 

The suit port is an element of the 

was located on the aft bulkhead o

doff aids as well as exterior platfo

mockup suit ports are shown in F

25 

ior cameras and microphones for human factors evalua

he SPR by which the crew performs EVAs. The su

d of the SPR cabin structure and included interior s

tforms to accommodate crewmembers of differen

Figure 15 and Figure 16. 

uations.

 suit port mockup 

or suit don and 

ent heights. The 
26 

Figure 15 – Rear view of SPR showing mockup suits attached to suit ports. 
27 

Figure 16 – A crewmember detaching from the SPR suit port. 

Initial human factors evaluation of the suit ports was performed at JSC in the Building 9 high 

bay and the “Rock Yard” facility. This testing continued during the October field test, when four 

crewmembers repeatedly used the suit ports during the 1-day and 3-day SPR traverses. 

The human factors evaluation of the suit port mockup (at JSC and during the October field test) 

focused on the following specific features and functions of the suit port: 

Suit don and doff capabilities and features of the suit port architecture: 

- Location and usability of interior handholds for suit don and doff 

- Usability of an “ottoman” as an interior booster seat for suit don and doff 

- Usability of exterior handrails for alignment guides and positioning during suited 

ingress operations 

- Leg angle positioning for suit don and doff operations 

- Adequacy of adjustable exterior platform heights for various crewmembers 

Features of suit undocking from and docking to the suit port / hatch interface area: 

- Usability of the actuator to unlock and lock the inner hatch 

- Usability of the actuator to close and open the inner hatch 

- Method of closing and opening the PLSS to the suit 
28 

- Usability of the actuator to unlock and lock the closure mechanism attaching the suit 

to the suit port entry hatch 

- Ability of a suited test subject to detach and reattach the suit to the suit port 

- Alignment guides and exterior platform height 

- External umbilical access and functional operation characteristics 

However, it is important to note that a) the suit port did not pressurize (a pressurized engineering 

unit has since been fabricated), b) the mockup suits were unpressurized and were not specifically 

designed for use with suit ports, c) the testing was performed in a 1-g environment, and d) the 

mockup suits and suit ports did not incorporate the additional complexities associated with an 

actual PLSS and the data, power, gas, and fluid connections between the suits and the SPR. 

Testing in a 1-g environment using unpressurized suits that are not specifically designed for use 

with suit ports is likely to increase the time and difficulty associated with suit port egress and 

ingress tasks, whereas the reduced complexity of the suit port mockup compared with that of a 

fully functioning pressurized version will mean that EVA overhead and technical challenges 

associated with this complexity were not identified during this study. Results of the suit port 

evaluation are presented and interpreted within the context of these limitations. Further 

discussion of the use of mockup EVA suits is in the following section. 

2.2.2.2 Mockup MkIII Spacesuits and EVA Tools 

The Mark III (MkIII) suit, also called the H-suit, represents a hybrid spacesuit configuration in 

that it is composed of hard elements such as a hard upper torso and hard brief section and of soft 

components such as the fabric elbows and knees. A key feature of the suit is its use of bearings 

in multi-axis mobility joint systems. The MkIII has bearings at the shoulder, upper arm, waist, 

upper hip, mid-hip, upper leg (3 bearing hip), and ankle joints. The suit is donned through a rear 

entry hatch. Subjects are integrated to the suit by a waist belt weight relief system and shoulder 

straps. The boots of the H-Suit are modified Extravehicular Mobility Unit (EMU) boots. The 

stiff fiberglass sole of the EMU boot was replaced with a commercial work boot sole. The MkIII 

suit weighs about 55 kg. Figure 17 below shows the MkIII suit as tested at the Desert Research 

and Technology Studies (RATS) 2006 remote field test. 
29 

Figure 17 – Mark III suit at Desert RATS 2006. 

The MkIII supports testing that assists with requirements development for future exploration 

class EVA systems. Some testing requires a suit that weighs less than the MkIII but is similar in 

appearance and with similar mobility limitation features, such as the three-bearing hip. Using 

lightweight suits minimizes injury risk, and they more closely represent the suit weights that will 

be experienced by astronauts on the lunar surface. 

Global Effects, Inc. designed and fabricated eight lightweight suits modeled after the MkIII to 

use in the movie industry. An additional suit was fabricated for NASA Headquarters to use as a 

Public Affairs Office display model. In June 2008, Global Effects, Inc. delivered four mockup 

suits to NASA JSC. These lightweight mockups were modeled after NASA’s MkIII suit. Figure 

18 shows two of the four MkIII mockup suits that were delivered. 
30 

Figure 18 – Two Global Effects, Inc. MkIII Mockup Suits. 

The mockup suits weigh about 28 kg, are cosmetic representations of the MkIII suit, and have 

mobility limitations similar to those of the MkIII suit (for example, waist bearing, hip bearings, 

and shoulder convolutes). The suits have the following parts: 

- Hard Upper Torso in fiberglass with correct hemisphere size, PLSS latch system, 

internal shoulder and waist harness, shoulder bearings, and a switch for the vent fan 

system 

- Hemispherical visor with a simple smoke sun visor with lift tabs and sun visor cover 

- Functional rolling convolute shoulders, with aluminum and cast metal 

- Sleeves made from nylon with anodized aluminum bayonet-style wrist disconnects 

- Glove Thermal Micrometeoroid Garments (TMGs) in Teflon with silicone palms 

- Waist bearing 

- Hip rotary joints with bearings in fiberglass 

- Legs made from nylon fabric 

- Shuttle-style PLSS volume with vent pressure fan system and batteries 

- Removable and machine-washable liners for sleeves and legs 

- Bearing spacers for torso and waist in 1′′ and 1⁄2′′ increments 

- Combat-boot style integrated with ankle ring 

Two of the four suits were modified to interface with the SPR suit port. Changes included the 

addition of an interface plate to the rear entry hatch, increasing the Portable Life Support System 

(PLSS) volume, and addition of a communication system, a GPS, and a data logger. 

During EVA activities, subjects were prompted for self-reported ratings of discomfort and 

exertion (see Section 2.3.7). If a subject reported a discomfort rating > 7 (on the Corlett and 

Bishop 10-point discomfort scale) for two consecutive recording periods during suited testing, 
31 

the subject was asked to doff the suit and continue the test wearing a lightweight backpack 

alternative that incorporated communications hardware and a GPS data logger. If a subject had 

reported a discomfort rating > 7 (on the Corlett and Bishop 10-point discomfort scale) for two 

consecutive recording periods during lightweight backpack operations, that specific test would 

have been terminated. 

Although the mockup suits have mobility limitations similar to those of the real MkIII suits, it 

should be noted that the mockup suits have several additional limitations. The objectives of this 

study did not require a pressurized planetary spacesuit prototype such as the MkIII. Indeed, the 

crewmember fatigue that results from the ~100kg (220lb) pressurized suits would have made 

completion of this test impossible and would have confounded the data by simulating a suit mass 

of more than 1000kg (2200lb). The Mockup MkIII suits enabled evaluation of the suit ports 

while also enabling completion of simulated EVAs lasting up to 8 hours. However, human 

performance data in the Mockup MkIII suits during this test is not representative of performance 

in the lunar environment. 

The EVA Physiology, Systems and Performance (EPSP) project has conducted studies which 

demonstrate the limitations of pressurized suits in 1-g test conditions and shows that no existing 

suit prototype or mockup suit accurately reflects lunar metabolic profiles. Detailed reports on 

these studies are available from the EPSP project. 

2.2.2.3 Communications, Networking and Navigation Infrastructure 

The Information Technology and Communications Directorate (ITCD) at Kennedy Space Center 

(KSC) was responsible for engineering, implementing, testing, and deploying operationally a 

diverse communications and networking infrastructure to support test operations. This 

infrastructure is known as a Lunar Communications and Network Emulator (LCNE), and the 

system was deployed to model an Agency Lunar Comm and Network architecture to evaluate the 

architecture and identify gaps in planning. 

Figure 19 - Lunar communications architecture modeled at D-RATS 2008.
32 

The KSC ITCD team provided the following major areas of support: 

• Installed communication and networking assets on nearby Elden Mountain to serve as 

aggregate broadband network bandwidth to the field test from a commercial Internet 

service provider 

• Secured the network from Internet attacks, and tunneled test site traffic back to NASA’s 

networks 

• Measured network utilization and performance useful for future lunar data requirements 

planning 

• Engineered and deployed a duplicate network tunnel from a JSC location to allow 

engineers to test their field configuration before the outing during dry run operations 

• Engineered, tested, and deployed the entire test site video, voice, and data network, which 

included multiple routers, switches, and even tactical fiber deployment at the test site 

• Engineered, fabricated, tested, and deployed a mockup Lunar Communication Terminal 

(LCT) 

• Provided spectrum management leadership for the entire D-RATS test team 

• Engineered, fabricated, tested, and deployed pan/tilt/zoom cameras that were remotely 

controlled throughout the field test 

• Engineered and fielded on-suit EVA megapixel science cameras and associated science 

CAPCOM image and video stream data display system 

• Assisted with design and testing of SPR rover audio and radio system 

• Validated performance of a low-data-rate high-definition mobile camera standard for 

lunar rovers and suits 

Navigation and asset tracking and recording for the rovers at the field test was facilitated through 

the use of the U.S. Global Positioning System (GPS). Use of the U.S. GPS system was adequate 

for the purposes of navigating traverses during this test and recording the progress of the 

operations. Future tests will involve the utilization of navigation techniques that more accurately 

model the lunar navigation architecture. 

2.2.2.4 Mobile Mission Control Center 

The KSC ITCD Mobile Mission Control Center (MMCC – Figure 20) was deployed at the base 

camp to accommodate the test support team, which included Capsule Communicator 

(CAPCOM), Traverse Director, Human Factors, Rover, Science Backroom, and Networking 

personnel. 
33 

Figure 20 – Mobile Mission Control Center (MMCC). 

2.2.2.5 SPR Exercise Ergometer 

The SPR contained a fully functional exercise ergometer (Figure 21). The device and its 

integration within the SPR were included in the human factors evaluation of the SPR crew 

accommodations. 
34 

Figure 21 – SPR exercise ergometer. 

2.2.3 HARDWARE INSPECTION

Before the start of each phase of this study, NASA Safety evaluated all hardware at test readiness 

reviews. Before and after each test session, the test operators visually inspected all testing 

equipment to ensure hardware safety. 

2.3 METRICS AND HYPOTHESES TESTING

Descriptive statistics were used to characterize the performance, productivity, and human factors 

metrics under all test conditions. Inferential statistics were not utilized to test the study 

hypotheses (Section 0) because the study had low statistical power. Instead, practically 

significant differences in specific metrics were prospectively defined for the testing of the study 

hypotheses. This process has been used during previous EVA suit-testing protocols conducted 

by the EVA Physiology, Systems, and Performance Project in which small sample sizes 

precluded the use of inferential statistics. For example, a practically significant difference in 

metabolic rate has been defined as ≥ 3.5 ml/kg/min, which is about equal to a person’s resting 

metabolic rate and also corresponds to the difference in metabolic rate that a person can perceive. 

The specific metrics used to evaluate each of the study hypotheses are described in the following 

sections. For comparative hypotheses, the difference value for each metric that was considered 

practically significant is defined and the rationale explained. For noncomparative hypotheses, 

the absolute value of each metric that accepted or rejected each hypothesis is defined and the 

rationale explained. 
35 

2.3.1 HYPOTHESIS 1: COMPARING PRODUCTIVITY AND EVA SUIT TIME

Hypothesis 1: Productivity achieved during 1-day exploration, mapping, and geological 

traverses using the Small Pressurized Rover (SPR) will be equal to or greater than the 

productivity achieved during Unpressurized Rover (UPR) traverses, with less EVA suit time. 

EVA suit time was recorded on data sheets during all traverse operations. Two methods of 

quantifying traverse productivity were used during this study: Pavilion Lake Research Project 

(PLRP) Traverse Science Merit Rating and Scientific Productivity Index (SPI). Each metric was 

developed and used to quantify a different aspect of the productivity, as described below. 

Metric: Pavilion Lake Research Project Traverse Science Merit Rating 

The Pavilion Lake Research Project (PLRP) uses a 1-5 Likert scale to quantify the scientific 

merit of submersible research traverses, shown in Table 3. The scientific merit of each traverse 

with respect to predefined scientific questions is rated before and after the traverse is performed. 

For each defined science question, the pre-traverse rating is a measure of the anticipated merit of 

that traverse with respect to that question. The post-traverse rating measures the actual scientific 

merit, that is, the extent to which that traverse will enable the science question to be answered. 

The merit of each traverse is also rated 2 years post traverse, after data from the traverse have 

been analyzed and possibly published. All ratings are based on the consensus of 4 or more 

subject matter experts. The PLRP Science Merit Rating was applied to each of the DRATS 2008 

field test traverses. The science merit data sheet completed before and after each traverse is 

shown in Table 4, including the specific science questions identified by the DRATS Science 

Team. 

Table 3 – Pavilion Lake Research Project Traverse Science Merit rating scale. 

Practically Significant Difference and Rationale 

By definition, any change in category on the scale represents a qualitatively significant 

difference in the metric. The mean values of pre- and post-traverse science merit for traverses 

with each vehicle were compared, with a difference of 1 category or more being prospectively 

defined as a significant difference. 

 

METRIC DESCRIPTOR DEFINITION 

1 Limited Data provide limited scientific value 

2 Adequate Data reaffirm existing hypotheses and facts 

3 Significant Data elucidate existing hypotheses in new areas or detail 

4 Exceptional Data resolve a major scientific question or highly significant hypothesis 

5 Discovery Data introduce a novel idea or hypothesis 
36 

Table 4 – Science questions addressed by UPR and SPR traverses at Black Point Lava Flow. 

Metric: Scientific Productivity Index

The Scientific Productivity Index (SPI) metric enables relative comparison of the productivity of 

different traverses in the same region. Whereas the PLRP Science Merit metric quantifies the 

scientific merit of a traverse as a whole, the SPI provides a measure of the success with which 

each predefined traverse objective is accomplished. Each traverse objective is assigned a value 

(VTO) before the traverse begins and, for each objective, the quality of data (DQ) collected 

during the traverse is rated according to a data quality scale. 

Scientific Productivity Index = ∑ VTO (n) × DQ (n) 

where 

VTO (n): value of traverse objective n, on a 1–3 scale 

 1 = low anticipated scientific importance 

 2 = moderate anticipated scientific importance 

 3 = high anticipated scientific importance 

DQ (n): Quality of data collected at traverse waypoint objective n, on a 0–4 scale 

Science Question Pre-Traverse 

Science Merit 

Post-Traverse 

Science Merit 

1 Will observations and samples collected allow 

characterization of Black Point Lava Flow 

(BPLF), in particular its age, morphology, 

structure, petrology, mineralogy, chemistry, 

and spatial and temporal variations? 

2 Will observations and samples collected allow 

characterization of the Marbled Unit, in 

particular its age, morphology, structure, 

petrology, mineralogy, chemistry, and spatial 

and temporal variations? 

3 Will observations and samples collected allow 

characterization of other geologic units and 

their relation to the BPLF in space and time? 

4 Will observations and samples collected allow 

determination of the geologic history of the 

site and determine the absolute ages of the 

major units in so far as possible? 
37 

The Pavilion Lake Research Project Data Quality Scale is a metric originally developed and used 

to quantify the quality of data collected during sorties performed by submersibles equipped with 

video cameras and manipulators. The scale is shown in Table 5. 

Table 5 – Pavilion Lake Research Project Data Quality Scale. 

 DESCRIPTOR DEFINITION 

0 No data No data or other relevant observations were made. 

1 Limited 

Video and navigation did not support scientific observations and other relevant data 

was of limited use. 

2 Adequate 

Quantitative data adequate for general documentation of findings. Provides useful 

context and enables efficient return. Data is marginally publishable. 

3 Significant 

Quantitative data adequate to support specific documentation of scientific findings 

and yielding publishable results. 

4 Exceptional 

High quality video, navigation, and other quantitative data that supports and 

enhances scientific merit. 

Thus, if no data were collected for a particular traverse objective of any value, the weighted sum 

for that objective would be zero. If exceptional data were collected for a traverse objective of 

high importance, a weighted sum of 12 would be assigned. 

Practically Significant Difference and Rationale 

The mean values for traverses with each vehicle were compared. A difference in SPI of 9 points 

reflected completion of one high priority science objective with high quality data and was 

considered a practically significant difference in productivity for the purposes of this test. 

Metric: EVA Suit Time 

Time spent inside the EVA suit increases suit-induced trauma and increases usage of 

consumables because of the evaporative cooling process. It was hypothesized that having the 

ability to make contextual geological observations from inside the SPR would mean that less 

EVA suit time would be required to achieve equal or greater productivity during 1-day SPR 

traverses than during 1-day geological UPR traverses. EVA suit time was manually recorded on 

data sheets during all traverse activities. The maximum and mean EVA suit time for each 

vehicle was calculated for the 1-day and 3-day traverses. 

Practically Significant Difference and Rationale

A difference in mean or maximum EVA suit time of ≥ 10% was prospectively defined as 

practically significant. Although the relationship between EVA suit time and suit trauma is 

variable and difficult to quantify, the relationship between EVA suit time and consumables usage 

is better defined. 

2.3.2 HYPOTHESIS 2: COMPARING RANGE

Hypothesis 2: The range achieved during 1-day exploration, mapping, and geological traverses 

in the SPR will be greater than during 1-day UPR traverses. 
38 

Metrics: Range, Distance Driven, Terrain Factor, Speed 

The different capabilities of the SPR and UPR mean that greater range is achievable using the 

SPR. Range as well as distance driven and speed (average and maximum) of each traverse were 

measured using GPS. The means of the maximum range for each of the 1-day traverses using 

each vehicle were calculated and compared as the test of Hypothesis 2. 

Practically Significant Difference and Rationale 

A difference in mean of maximum range or distance driven of ≥ 10% was prospectively defined 

as being practically significant. 

2.3.3 HYPOTHESIS 3: CONTEXTUAL OBSERVATIONS

Hypothesis 3: Subjective assessment of contextual observations from inside an SPR will be equal 

to contextual observations from inside an EVA suit. 

Metric: Subjective Assessment of Contextual Observations 

A Subjective Assessment of Contextual Observations scale (Table 6) was used to evaluate the 

ability of four subjects (members of the science team) to make contextual observations from 

inside the SPR compared with observations from inside an EVA suit. 

Table 6 – Subjective Assessment of Contextual Observations scale. 

 DESCRIPTOR DEFINITION 

1 Limited Observation quality is significantly limited by the vehicle compared with that 

achievable by the same person, in the same amount of time, walking shirtsleeve. 

2 Adequate 

Observation quality is adequate; marginally limited by the vehicle compared with 

that achievable by the same person, in the same amount of time, walking 

shirtsleeve. 

3 Shirtsleeve 

Equivalent 

Observation quality is not limited by the vehicle; equivalent to that achievable by 

the same person, in the same amount of time, walking shirtsleeve. 

4 Exceptional 

Observation quality is enhanced by the vehicle; exceeds that achievable by the 

same person, in the same amount of time, walking shirtsleeve (for example, due to 

accessibility, use of cameras and sensors, elevation, intra-site translation speed) 

Subjects rated their own Geological Observation Quality when inside the vehicle. The rating was 

not a measure of the quality of data collected nor was it a measure of the expertise of a 

crewmember; it was a measure of the extent to which the vehicle enabled subjects to make 

geological observations at a particular traverse station. A rating of 3 indicated that the quality of 

observations was equivalent to that which could be achieved by the same person, in the same 

amount of time, while walking in “shirtsleeves.” Comparison with suited EVA operations was 

not performed during this test. 

In addition to assigning a rating, reviewers made note of the significant factors that enhanced or 

inhibited subjects’ ability to make geological observations, including vehicle features and 

capabilities (such as use of cameras and sensors, elevation of subjects, intra-site translation 

speed, and trafficability) and also features of the station (such as slopes, blockiness, and 

geology). 

Practically Significant Difference and Rationale 
39 

By definition, any change in category on the scale represents a qualitatively significant 

difference in the metric. It was hypothesized that the mean rating among all geologists would be 

about equal to 3. 

 2.3.4 HYPOTHESIS 4: SUIT PORT HUMAN FACTORS

Hypothesis 4: Human interfaces with the SPR suit ports and alignment guides will be acceptable 

as assessed by human factors metrics. 

Metric: Subjective Ratings of Suit Port Human Factors 

The following Likert scale was developed to evaluate the acceptability of SPR suit ports and 

alignment guides: 

Crewmembers were asked to evaluate the following aspects of the suit ports and alignment 

guides: 

1) Overall human factors 

2) Internal access 

3) Interior handholds 

4) General IVA operations 

5) External access 

6) External handholds 

7) General EVA operations 

8) Donning of suit 

9) Doffing of suit 

10) Interior vehicle volume for donning 

11) Interior vehicle volume for doffing 

12) Translation into suit port 

13) Translation out of suit port 

Hypothesis Accept-Reject Criteria and Rationale 

To test the hypothesis, median ratings of overall human factors were calculated. By definition, 

ratings of ≤ 4 indicated acceptable human factors. However, even where median values were ≤

4, the reasons for any outlying data points > 4 (that is, unacceptable human factors) were 

recorded to help inform the redesign of the suit ports and alignment guides. 

2.3.5 HYPOTHESIS 5: HUMAN FACTORS DURING 3-DAY TRAVERSE

Hypothesis 5: The human factors and crew accommodations within the SPR will be acceptable to 

support a 3-day exploration, mapping, and geological traverse. 
40 

A combination of existing human factors metrics and customized questionnaires were used to 

evaluate the acceptability of the SPR and UPR human factors. Data collection intervals were 

incorporated into the detailed EVA timelines. Data were collected primarily using data sheets, 

but data from built-in video cameras inside the SPR (Figure 14) were also analyzed after the field 

test to yield additional usability information. Data were collected daily to assess any trends that 

might suggest that the acceptability of the human factors and crew accommodations were 

decreasing as the 3-day traverse continued. 

Metric: Subjective Ratings of SPR Human Factors 

A questionnaire and interview were completed at the end of each traverse day. Five groups of 

questions concerned the functionality of the SPR in the areas of driving, visibility, cockpit 

displays and controls, seating, and EVA. One group of questions focused on overall acceptability 

of each vehicle configuration. The same Likert scale used in assessing suit port human factors 

was used: 

The post-traverse questionnaire also had four open-ended questions about the limiting factors for 

performance, the overall configuration, changes in configuration that could make traverses more 

efficient, and any additional comments that were not covered in the ratings. 

Hypothesis Accept-Reject Criteria and Rationale 

By definition, ratings of ≤ 4 indicated acceptable human factors. However, even where mean 

values were ≤ 4, the reasons for any outlying data points > 4 (that is, unacceptable human 

factors) were recorded to help inform the redesign of the vehicle. 

Metric: Cooper-Harper Rating of Vehicle Handling Qualities

One aspect of the human factors evaluation is the handling qualities of the vehicle. The CooperHarper rating of vehicle handling qualities is shown in Figure 22 and was used in evaluating 

UPR and SPR vehicle handling qualities. 

Hypothesis Accept-Reject Criteria and Rationale 

As Figure 22 shows, a Cooper-Harper rating of 3 corresponds to “Satisfactory without 

improvements” with “minimal compensation required for desired performance.” For the 

purposes of this evaluation, a Cooper-Harper rating of ≤ 3 was therefore considered acceptable. 
41 

Figure 22 – Cooper-Harper rating for vehicle handling qualities. 

Metric: Modified Cooper-Harper Rating

In addition to evaluating the vehicle handling qualities, the degree of operator compensation 

required for operation of SPR displays and controls was also quantified. The modified CooperHarper rating of operator compensation has been successfully used during multiple NASA/JSC 

Integrated Suit Testing protocols. The scale is shown in Figure 23.

Hypothesis Accept-Reject Criteria and Rationale 

The study hypotheses required that the acceptability of human factors be assessed. For this 

purpose, a Modified Cooper-Harper rating of ≤ 3 was considered acceptable. As Figure 23 

shows, a Cooper-Harper rating of 3 corresponds to “Satisfactory without improvements” with 

“minimal compensation required for desired performance.” 

 
42 

Figure 23 – Modified Cooper-Harper rating of operator compensation. 

Metric: Fatigue Rating 

The following Likert scale was defined to measure fatigue during the 1-day and 3-day traverses: 

Unlike Borg’s Rating of Perceived Exertion scale, which measures acute exertion during a 

particular activity, the fatigue scale measures the level of underlying fatigue that a crewmember 

feels while resting. Fatigue was measured at the beginning and end of each traverse day. 

Hypothesis Accept-Reject Criteria and Rationale 

By definition, ratings of ≤ 4 indicate that subjects are not fatigued to an extent that would 

compromise performance. A rating of > 4 would indicate unacceptable fatigue, which might 

indicate inadequate human factors or crew accommodations or an overly demanding traverse 

timeline. 

 
43 

2.3.6 OTHER TEST OBJECTIVES

6) Perform nighttime driving and exploration, mapping, and geological sample collection 

and documentation tasks using SPR and UPR vehicles. 

7) Measure performance metrics during 1-day and 3-day (SPR only) exploration, mapping, 

and geological traverses. 

Several parameters were categorized as performance metrics. As described above, some metrics 

were used to test specific study hypotheses, while others were collected and compared with 

performance estimates used in existing Lunar Surface Systems and Human Research Program 

engineering and physiological models, as noted in the Hypotheses and Test Objectives (Section 

1.2). Several metrics are inputs to engineering and physiological models used by the 

Constellation Program. The metrics not specifically used in the testing of study hypotheses but 

used to meet Test Objectives 6 and 7 are described below: 

Metric: EVA Boots-on-Surface Suit Time 

EVA boots-on-surface suit time is generally the time during which greatest scientific 

productivity is being achieved. Time spent inside the EVA suit during vehicle ingress and egress 

is considered nonproductive EVA time. By comparing EVA suit time to EVA boots-on-surface 

suit time, the efficiency with which EVA suit time is used may be quantified. Physiological 

modeling of the ameliorating effects of EVA exercise on bone and muscle atrophy also requires 

estimates of EVA boots-on-surface suit time. 

Practically Significant Difference 

Not applicable (metric not directly used in hypothesis testing). 

Metric: Number of EVAs 

The number of EVAs performed during traverses affects the consumables lost during ingress and 

egress operations, the energy required to operate gas reclaim pumps (with airlock) and the 

number of egress/ingress cycles on suit ports or the Mobile Habitat airlock. Although it was 

anticipated that having suit ports on the SPR would mean that EVAs from an SPR are typically 

shorter and more frequent, this had not been verified during operations. It was possible that the 

terrain and distribution of traverse stations would make even the rapid SPR egress and ingress an 

inefficient use of time. 

Practically Significant Difference and Rationale 

Not applicable (metric not directly used in hypothesis testing). 

Metric: EVA Distance Walked

Physiological modeling of the ameliorating effects of EVA exercise on bone and muscle atrophy 

requires estimates of typical EVA walking distances. These data are also valuable in estimating 

the number of joint cycles on EVA suit components. 

Practically Significant Difference 

Not applicable (metric not directly used in hypothesis testing). 

Metric: EVA Task Completion Times 
44 

Subjects verbally communicated to the CAPCOM when tasks were started and finished. Times 

were recorded using data sheets and the duration of each task was calculated. 

Practically Significant Difference and Rationale 

Not applicable (metric not directly used in hypothesis testing). 

Metrics: Range, Distance Driven, Terrain Factor, Speed

Quantifying the range achieved and distances driven during multi-day exploration, mapping, and 

geological traverses in a lunar-like environment enables improved estimation of exploration 

range from a fixed lunar outpost and the development of a Global Coverage Map. The model 

used to size the solar arrays and energy storage systems on lunar surface mobility systems 

requires estimates of these metrics. Current inputs for this model are speculative and will be 

compared with field test data from this study. The range achieved and power usage are affected 

by vehicle speed and terrain factor, which is equal to the distance driven divided by range 

achieved (for a one-way traverse). 

2.3.7 SUBJECTIVE CREW HEALTH METRICS

Subjects were prompted at intervals of not more than 30 minutes during all traverses for 

subjective ratings on each of the following scales: a) Thermal Comfort Scale (Bedford, 1936), 

b) Discomfort Scale (Corlett and Bishop, 1976), and c) Perceived Exertion Scale (Borg, 1982). 

Because of the limitations of the 1-g test environment and the mockup MkIII suits, the data were 

not used in a comparative sense; the data were used to ensure the health and safety of the 

subjects throughout the field test and to identify any deficiencies in test equipment. The use of 

subjective crew health metrics as Test Termination Criteria is described in Section 2.2.2.2. The 

scales are shown in Tables 7-8 and Figure 24. 

Table 7 – Bedford Thermal Comfort Scale. 

Bedford Thermal Comfort Scale 

-3 Much too cool 

-2 Too cool 

-1 Comfortably cool 

0 Comfortable 

1 Comfortably warm 

2 Too warm 

3 Much too warm 

The Corlett-Bishop Discomfort Scale (Figure 24) is a subjective self-reported scale in which 

participants indicates their level of physical discomfort and the area of the body where the 

discomfort is located. Because of the limitations of the 1-g test environment and issues 

concerning the mockup Global Effects MK III suits, data from the Corlett-Bishop Discomfort 

Scale were primarily used to ensure crew health and safety throughout the field test. However, 

discomfort ratings at the start and end of each day during the 3-day traverse were used to 

determine whether any time-dependent discomfort was developing as the traverse progressed. 

 
45 

Figure 24 – Corlett and Bishop Discomfort Scale (Corlett & Bishop, 1976). 

Table 8 – Borg Rating of Perceived Exertion Scale. 

BORG RATING OF PERCEIVED EXERTION SCALE

6 No exertion at all 

7 Extremely light 

8 

9 Very light (easy walking slowly at a comfortable pace) 

10 

11 Light 

12 

13 Somewhat hard (quite an effort; you feel tired but can continue) 

14 

15 Hard (heavy) 

16 

17 Very hard (very strenuous, and you are very fatigued) 

18 

19 Extremely hard (you cannot continue for long at this pace) 

20 Maximal exertion 

 

A1

C1 B1

D1

E1

F1

Front of Participant

G1 H1

I1 J1

K1

M1

O1

L1

N1

P1

A

B C

E

H

D

F

G

L

I

K

J

M

N O

P Q

R S

T U

V

X Y

W

Back of Participant

10 Extremely High Discomfort 

9

8

7 Very High Discomfort 

6

5 High Discomfort 

4

3 Moderate Discomfort 

2 Low Discomfort 

1 Very Low Discomfort 

0.5 Extremely Low Discomfort 

0 Nothing at All 

Discomfort Scale

Q1 R1

S1 T1

OF NF

Z1 Z
46 

3.0 RESULTS AND DISCUSSION

Results of the field test are presented and discussed in the following pages. Results are presented 

in order according to the hypotheses and test objectives described in Section 0. 

3.1 HYPOTHESIS 1: COMPARING PRODUCTIVITY AND EVA SUIT TIME

Hypothesis 1: Productivity achieved during 1-day exploration, mapping, and geological 

traverses using the Small Pressurized Rover (SPR) will be equal to or greater than the 

productivity achieved during Unpressurized Rover (UPR) traverses, with less EVA suit time. 

Comparison of UPR and SPR traverse productivity as measured by the Scientific Productivity 

Index (SPI) showed that productivity during 1-day SPR traverses was an average of 25.5 points 

(or 57%) greater than during equivalent 1-day UPR traverses (Figure 26). 

As described in Section 2.3.1, a difference in 

SPI of 9 points reflects completion of one highpriority science objective with high-quality data 

and was prospectively defined as a practically 

significant difference in productivity for the 

purposes of this test. Thus, a difference of 25.5 

points meets and exceeds the prospectively 

defined criteria for significantly greater 

productivity and indicates that SPR 1-day 

traverses achieved almost three more highpriority science objectives with high data 

quality than the corresponding UPR traverses. 

A difference in mean or maximum EVA suit 

time of ≥ 10% was prospectively defined as 

practically significant. As shown in Figure 25, EVA suit time during 1-day SPR traverses was 

61% less than during the corresponding UPR traverses. 

Normalization of productivity, as measured by SPI, by EVA suit time yields the performance per 

EVA hour. When combined with the productivity and EVA suit time data collected during days 

Figure 25 - UPR vs. SPR: Total EVA suit time 

(average per crewmember). 

Figure 26 - UPR vs. SPR: Performance (Scientific 

Productivity Index).

Figure 27 - UPR vs. SPR: Performance per EVA hour.
47 

2 and 3 of the 3-day SPR traverse, the average productivity per EVA hour during SPR traverses 

was 4.7 times greater than during UPR traverses (Figure 27). 

There are several reasons behind the large increase in productivity per EVA hour. In addition to 

being inside the SPR during long translations, the ability to make contextual observations from 

inside the SPR means that boots-on-surface EVA time at each site – if any – is spent on 

refinement of those observations and targeted sample collection. And when intravehicular 

observations indicate that EVA is warranted, in many cases it is only necessary for one 

crewmember to egress the SPR. Subjects also noted that the ability to easily and clearly 

communicate with each other about geological observations while inside the SPR was greatly 

superior to the UPR, which in turn led to greater productivity. 

Although the Science Merit Rating metric developed by the Pavilion Lake Research Project (see 

www.pavilionlake.com) was also used to compare the science merit of UPR and SPR traverses, 

the UPR and SPR traverses yielded consistently low science merit ratings because of the fact that 

the geology of the Black Point Lava Flow has already been extensively studied and the data 

collected during the SPR and UPR traverses added little to what was already known about the 

area. Of course, the purpose of the traverses was to compare the capabilities of the UPR and 

SPR vehicle concepts rather than to advance terrestrial scientific knowledge, and the science 

merit rating was intended only to provide another method of comparison. However, the metric 

did not prove useful in this respect as the science merit in all cases was consistently low. 

3.2 HYPOTHESIS 2: COMPARING RANGE

Hypothesis 2: The range achieved during 1-day exploration, mapping, and geological traverses 

in the SPR will be greater than during 1-day UPR traverses. 

The maximum range achieved during 1-day SPR traverses was 5.3 km compared with 5.0 km 

during UPR traverses. A difference of ≥ 10% was prospectively defined as a significant 

difference in range. The observed difference of 6% was therefore not significant. Average 

distance driven during each traverse was also compared, which showed 4.3 km (31%) greater 

distance driven during SPR traverses. 

The observed increase in traverse distance 

without a corresponding increase in range 

was due primarily to communications 

constraints at the field test site. Although 

SPR operations in intentionally degraded 

communications coverage are planned for 

DRATS 2009, it was decided that the 2008 

field test would be performed with 

continuous real-time communications 

between the rover vehicles and the MMCC, 

in which the mission operations and 

science teams were located. 

The primary constraint limiting the distance 

and range of UPR traverses is the power 

and consumables in the EVA suit PLSS. 

Although the mockup EVA suits used during this test did not use an actual suit PLSS, the 

Figure 28 - UPR vs. SPR: Traverse Distance and 

Range.
timelines were developed and exe

assumptions used when developin

2.1.6. 

The limitations of the test therefo

would achieve greater range than

same limitations is expected to co

3.3 HYPOTHESIS 3: CONTEX

Hypothesis 3: Subjective assessm

to contextual observations from i

Four experienced field geologists

protocol described in Section 2.1.

inside the SPR with observations 

four field geologists rated their ob

“observation quality is not limited

person, in the same amount of tim

observations as a 2.5, indicating s

compared with shirtsleeve. 

Particularly given that the compa

the hypothesis that subjective ass

equal to suited contextual observa

suits are required to assess wheth

inside an EVA suit. 

The Moenkopi outcrop was readi

to reach the basalts in the outcrop

consequence, all basalt observatio

ejecta that cover most of the luna

All geologists elected to drive sid

the outcrops with the front of the

outcrops, starting with the Moenk

and then getting as close as possib

basalt outcrops. Most of the drive

was spent getting upslope and do

many observations related essenti

mapping, with detailed descriptio

diversity of basalt textures and pu

searches for the basalt/sandstone 

happened to be buried under the f

location. 

Analysis of the post-test question

completed by each geologist reve

observations made from the SPR 

in some respects and inferior in o

strengths and weaknesses balanc

48 

executed based on flight-like constraints and assum

ping timelines for UPR and SPR traverses are deta

efore precluded valid testing of the hypothesis that

an UPR traverses. However, future analog testing

 confirm this intuitive hypothesis. 

EXTUAL OBSERVATIONS

sment of contextual observations from inside an SP

 inside an EVA suit. 

sts from the DRATS Science Team completed the

.1.3, which compared the quality of geological ob

s made by the same person walking in shirtsleeve

 observations from inside the SPR as a 3.0, indicat

ited by the vehicle; equivalent to that achievable b

time, walking shirtsleeve.” The fourth geologist ra

g slight decrements in observational quality from i

parison was made with shirtsleeve rather than suit

ssessment of contextual observations from inside 

rvations was accepted. Future evaluations using lig

ether SPR-based observations are superior to those

dily reached by the SPR, yet the slope was too ste

rop; the basalt outcrops were just outside the test a

ations related to dislodged float, a good analog for 

nar surface.

sideways along 

he SPR facing the 

enkopi sandstone 

ssible to the 

ive, however, 

down again, and 

ntially to float 

tions of the 

 purposeful 

ne contact, which 

e float at this 

onnaires 

veals that 

R were superior 

n others; and the 

nced out overall. 

Figure 29 - Field geologist ratings

geological observat

umptions. The 

etailed in Section 

at SPR traverses 

ing without the 

 SPR will be equal 

he stand-alone 

observations from

eves. Three of the 

cating that 

 by the same 

t rated SPR 

m inside the SPR 

uited performance, 

de an SPR are 

 lightweight EVA 

se made from

steep and bouldery 

t area. As a 

or typical crater 

gs of SPR contextual 

ations.
This is consistent with the philoso

contextual observations from insi

sampling, particularly in less acce

was very positive. All comments

3.4 HYPOTHESIS 4: SUIT PO

Hypothesis 4: Human interfaces 

as assessed by human factors met

Thirteen different aspects of the h

were quantitatively assessed usin

the assessment are summarized in

acceptability ratings for each of th

day and 3-day SPR traverses perf

Figure 30 – Acceptability ratings for 1

The median ratings indicated that

aspects except for external access

Acceptable range. Median ratings

Therefore, the hypothesis that hum

accepted. However, the data and 

factors could be further improved

49 

osophy of using SPRs to reduce EVA time by mak

nside the vehicles and using EVA for follow-up ob

ccessible areas. Overall, geologist feedback on SP

nts provided by the field geologists are included in

PORT HUMAN FACTORS

es with the SPR suit ports and alignment guides wi

etrics. 

e human interfaces with the SPR suit ports and ali

sing the acceptability rating defined in Section 2.3.

in Figure 30, which shows the median, maximum

the 13 aspects of suit port usability. Results are b

erformed by both crews. 

r 13 aspects of SPR suit ports.

hat the human interfaces with the suit ports were a

ess and general EVA operations, which were in the

ngs of “overall human factors” were in the Accepta

human interfaces with the SPR suit ports are accep

d the follow-up questionnaires indicated that the s

d. The highest ratings for external access and gen

aking preliminary 

observations and 

SPR capabilities 

in Appendix C. 

 will be acceptable 

alignment guides 

.3.4. Results of 

um, and minimum 

e based on the 1-

e acceptable in all 

 the Borderline 

ptable range. 

ceptable was 

e suit port human 

eneral EVA 
50 

operations were 7, indicating that, even although human factors were acceptable overall, in some 

instances these aspects of the suit port human factors were unacceptable. 

The primary reasons reported for Borderline Acceptable ratings for external access were 

inadequate space between latching mechanism levers, which precluded simultaneous operation 

of levers on both suit ports, combined with minor deficiencies in the alignment guides. External 

handholds on the vehicle were also suggested to help maintain balance and each handhold should 

be strong enough for a crewmember to put all their weight on it if necessary. 

Borderline ratings for general EVA operations were attributable in part to the aforementioned 

issues about external access and also to the fact that the mechanism for actuating the Marman 

bars on the suit ports was found to be unreliable and required occasional support from 

technicians to assist subjects in securing and releasing the suits from the suit ports. In a flight 

suit port this would represent a serious safety issue, but a post-test redesign of the actuation 

mechanism for the Marman bars has already yielded significant improvements, and a separate 

effort to develop and test a higher fidelity pressurizable suit port engineering unit is ongoing. 

The development and testing of a safe and robust suit port is a central component of the plan for 

a future SPR; the purpose of testing the nonpressurized suit ports at DRATS 2008 was solely to 

evaluate the human interfaces of the preliminary suit port design concept. 

Human factors for translation into and out of the suit port were considered acceptable overall, 

although Borderline Acceptable ratings (5) were also recorded in both cases. Participants noted 

that donning or doffing the suit while the vehicle was on a slope was difficult because the PLSS 

hatch was continually falling in on them. They also reported that when doffing the suit they were 

physically using their head to initially open the PLSS hatch. 

No issues arose with the internal volume in terms of donning and doffing of the suits. A 

cushioned ottoman was available to help aid suit translation but was used only 50% of the time. 

Participants reported that the interior handholds for the suit port and translating out to the suit 

port were acceptable. The chin up and dip bar were used the most when subjects were 

translating into or out of the suit in the suit port, but test subjects rarely used the side vertical bar. 

Descriptive statistics regarding suit port egress and ingress durations and frequency are in 

Section 3.6.2. 

3.5 HYPOTHESIS 5: HUMAN FACTORS DURING 3-DAY TRAVERSE

Hypothesis 5: The human factors and crew accommodations within the SPR will be acceptable to 

support a 3-day exploration, mapping, and geological traverse. 

As detailed in Section 2.3.5, a combination of existing human factors metrics and customized 

questionnaires were used to evaluate the acceptability of the SPR and UPR human factors. 

Results of the 3-day evaluation of SPR habitability are also documented in a separate report 

(Litaker et al, 2008). 

Overall, results indicated that the SPR prototype successfully met all objectives in terms of 

human performance and crew accommodations. In addition, the SPR adequately supported EVA 

operations through the use of suit ports and operational support for the EVA crewmember. 

However, several areas were identified where redesign could further increase performance and 

productivity. 
51 

For vehicle operations, participants needed better situational awareness of the SPR with respect 

to vehicle alignment capabilities and sideways driving. In addition, improvements in the displays 

and controls were suggested, specifically with respect to stability of the cockpit control and 

display quality in brightly lit conditions. Participants had difficulty with side window visibility 

that led to the issues with situational awareness and problems with the bright sunlight from the 

front windows that obscured the displays. 

It was discovered that the type of terrain did not adversely affect driving performance, but did 

have an effect on operating the display and controls because of vibration. With respect to EVA 

performance, the type of terrain was related to physical exertion and fatigue. In addition, 

participants had difficulty translating on and off the vehicle because of its height from the 

ground, and operation of the suit port external controls was problematic. Suggestions were to 

have more easily operated controls as well as guides for the crewmember sliding back into the 

suit port. 

Overall, the interior of the vehicle was rated as acceptable. Suggested minor improvements 

included better adjustability of cockpit seats, addition of a foot rest, and improved stowage. 

Participants found that, despite adequate volume within the vehicle, built-in stowage was 

inadequate and access to the stowage compartments was problematic. In addition, inadequate 

stowage space was allocated for waste, which accumulated quickly over the 3-day mission. The 

sleeping accommodations were found to be comfortable. 

The results of the SPR human factors evaluation are described in greater detail in Sections 3.5.1 

to 3.5.6 (adapted from Litaker et al., 2008). 

3.5.1 DRIVING-RELATED HUMAN FACTORS

A total of 12.5 hours of driving time was completed during the 3-day SPR traverse over a variety 

of terrain. Cooper-Harper ratings indicated that, regardless of the type of terrain, driving 

performance was at a desirable level with minimal operator compensation required (Figure 31). 

The one Cooper-Harper rating of 4 was recorded during night driving operations. These results 

suggest that although acceptable performance was achievable with driving, improvements could 

be made, especially for dark or nighttime driving conditions. 
52 

Figure 31 – Cooper-Harper ratings for driving the SPR during the 3-day mission; the size of the dot 

represents the number of scores at that rating (scale on top right). From Litaker et al, 2008. 

In addition to the Cooper-Harper ratings, 12 different aspects of driving-related human factors 

were rated by participants using the acceptability scale defined in Section 2.3.5. Results are 

summarized in Table 9. Ratings indicated that subjects experienced little fatigue while riding or 

driving. Straight forward driving, arc driving, and vehicle acceleration were all rated as 

acceptable. Participants indicated the need for better situational awareness by improving the 

lateral field of view (FOV) of the vehicle for crabbing and body alignment. Participants 

commented that for vehicle leveling, an inclinometer would be useful in the cockpit. In addition, 

they stated that minor improvements were needed for fine alignment driving and overall noise 

reduction, as well as vibration dampening, especially for the displays. 

Level 1 Level 2 Level 3

Number of 

Responses
53 

Table 9 – Acceptability ratings for SPR driving during 3-day traverse. 

Note: N=2. SA is situational awareness. Best = 1, Worst = 10.

3.5.2 DISPLAYS AND CONTROLS HUMAN FACTORS

Subjects rated the degree of operator compensation required when operating the SPR displays 

and controls using the Modified Cooper-Harper scale. While most Modified Cooper-Harper 

ratings for displays and controls were a three (minimal operator compensation required), there 

was some variability in the ratings, particularly during the first 2 days with ratings ranging from 

2 to 5 (Figure 32). This improvement in the consistency of ratings across the 3 days is assumed 

to be the effect of training or familiarity with the Displays and Controls as task difficulty did not 

change from day 1 to day 3. 

SPR Driving Tasks Day 1 Day 2 Day 3 Average

Straight away forward driving capabilities 3.00 3.00 3.00 3.00

Arcing driving capabilities 3.00 3.00 3.00 3.00

Fine alignment capabilities for driving 4.00 3.50 3.50 3.67

Sideways driving capabilities 3.50 4.00 3.50 3.67

Overall vehicle handling and steering capabilities 3.50 3.50 3.50 3.50

Vehicle leveling capabilities 3.00 3.50 3.50 3.33

Vehicle acceleration capabilities 3.00 2.50 3.00 2.83

Sound installation for noise reduction 3.00 4.00 4.00 3.67

Dampening for vibration while driving 3.00 4.00 3.50 3.50

SA of vehicle body alignment while driving 5.50 5.50 5.50 5.50

Physical fatigue while driving 3.00 3.00 2.50 2.83

Physical fatigue while riding 2.50 2.00 2.00 2.17

Overall Average 3.33 3.46 3.38 3.39
54 

Figure 32 – Modified Cooper-Harper ratings for the displays and controls interface 

 of the SPR over the 3 day mission. 

Subjects also rated 16 different aspects of the displays and controls using the acceptability scale 

defined in Section 2.3.5. The acceptability data (Table 10) indicate that improvements are 

warranted with respect to a) responsiveness of the touch screen, b) stability of the displays and 

controls while driving, c) display brightness during day operations, d) readability of the display 

while driving, e) adjustability of the display, and f) navigation of the display menu. 

Participants indicated that it was extremely difficult to accurately press a menu tab while both 

their body and the display were bouncing in the vehicle with bumpy terrain. Attempting to finetune a navigational waypoint or accessing the command menu was almost impossible while 

driving on certain terrains. At times, the participants had to stop the vehicle to access the menu. 

It was noted that a major issue was the stability of the arms that held the display, which tended to 

move up and down easily on bumpy terrain. Coupled with the already difficult task of accessing 

a specific menu, participants found the display frustrating to use while driving. Though 

participants rated the display adjustability unfavorably, they noted that it was easy to swivel their 

screen to another crewmember, which was helpful. 

Other issues with the display included menu lockouts of navigational pages and the complexity 

of selections on command menus. Subjects found that having to drill down several pages to find 

a certain command or navigational menu was both time-consuming and frustrating, especially 

over rough terrain. In addition to the issues of display complexity and number of levels, subjects Level 1 Level 2 Level 3

Number of 

Responses
55 

did not like the inconsistent use of color (such as black versus grey background, and each 

“button” being a different color), display density, and the replication of information on each 

display (for example, direction and waypoint indicator). 

Some difficulty reading the displays during daylight operations also compounded performance 

issues when subjects interfaced with the displays. The crew reported that sun glare made the 

displays ineffective and suggested either adding another display position within the cockpit that 

was shaded from the sun or adding some type of sun shade to the front window. However, for 

night operations, participants reported the display readability to be effortless and clear. Overall, 

the Cooper-Harper scores were borderline in meeting the rating criteria of 3, suggesting 

improvements are warranted. 

Table 10 – Acceptability ratings for SPR displays and controls during 3-day traverse. 

 Note: N=2. Best = 1, Worst = 10. 

3.5.3 VISIBILITY HUMAN FACTORS

Subjects rated the acceptability of 12 aspects of visibility (Table 11) using the acceptability scale 

defined in Section 2.3.5. 

On all days, the lack of window shading was found to be unacceptable with improvements 

mandatory. Currently, the SPR does not have any way of blocking sunlight from entering the 

cockpit. Some type of visor or film that could reduce the sun glare and reduce heat radiation 

within the vehicle is needed. Other suggestions included research on prototype window tinting, 

exterior vents or blinds, or reducing the size and angle of the front window. This issue alone 

caused problems with readability of display screens and increased eye fatigue. Particularly given 

SPR D&C Tasks Day 1 Day 2 Day 3 Average

Layout of the D&C in the rover cockpit 5.00 4.00 4.50 4.50

D&C within reach of your seating position 4.00 3.50 3.50 3.67

Touch screen responsiveness to your commands 5.00 6.00 6.00 5.67

Navigation of the display menus 4.50 4.00 3.50 4.00

Vehicle navigation displays understandable 4.50 5.00 3.50 4.33

Communications with ground support/EVA support 3.50 3.50 3.50 3.50

Adjustability of cockpit D&Cs 4.50 5.00 4.00 4.50

Stability of cockpit D&C during nominal driving 6.50 5.50 5.50 5.83

Readability of displays during driving 4.50 4.50 5.50 4.83

Display brightness for day operations 6.00 6.00 6.50 6.17

Display brightness for night operations 2.50 2.00 2.00 2.17

Eye fatigue with display while driving 3.00 3.00 3.50 3.17

Hand fatigue with controller while driving 3.50 3.50 3.50 3.50

Hand fatigue with display while driving 3.00 3.50 3.50 3.33

Eye fatigue with display while riding 3.00 3.00 3.50 3.17

Hand fatigue with display while riding 2.50 3.00 2.50 2.67

Overall Average 4.09 4.06 4.03 4.06
56 

the low sun angle at the south polar region of the Moon, further research is warranted to identify 

a solution to this problem. 

Table 11 – Acceptability ratings for SPR visibility during 3-day traverse. 

 Note: N=2. Best = 1, Worst = 10. 

Areas judged as needing minor improvements were eye fatigue while driving (mostly because of 

the shading issue previously discussed), visibility through the lower corner windows for driving 

and avoidance of obstructions, visibility of side windows for driving, and camera views for blind 

spots. Participants reported the lower corner windows were excellent for observing fine textures 

of soil but found them difficult to use for obstacle avoidance because they could not see the 

vehicle’s wheels. 

Side and aft views of the vehicle were difficult to nonexistent. A better lateral field of view out 

of the side windows for obstacle avoidance and vehicle body alignment for sideways driving is 

desired. Future side window concepts suggested were a bubble-type window similar to the lower 

bubble or a small diver-type mask inset in the window. Any window concept would need to be 

accessible from a seated position within the vehicle’s cockpit and should provide the 

crewmember an extended view of the side of the vehicle and a downward view of the wheels. 

For aft viewing, camera views with dedicated displays in the cockpit would improve visibility, 

but it is likely that whenever possible crewmembers will simply turn the vehicle around to obtain 

superior visibility through the windows rather than drive backward with a camera view. 

Participants rated visibility of the front windows for driving and lower bubble for observations as 

acceptable. Comments indicated enjoyment in the excellent viewing and likened it to watching 

an IMAX movie as they drove along the test site or observed some geological formation up 

close. In addition, the current window configuration contributed to the perception of the interior 

volume appearing more spacious. The lower bubble was found to enhance the ability to perform 

quality scientific study of sites to determine whether an EVA was needed, as well as allowing 

recording of the site as a reference for future geological activities. The geologist participants 

SPR Visibility Tasks Day 1 Day 2 Day 3 Average

Visibility of front window for driving 2.50 2.00 2.00 2.17

Visibility of side windows for driving 4.50 4.50 5.00 4.67

Visibility of lower corner windows for driving 4.00 3.50 3.00 3.50

Visibility of lower bubble for observations 2.50 2.00 2.00 2.17

Overall visibility to avoid obstructions 4.00 3.00 3.50 3.50

Camera views for blind spots 5.00 5.00 4.50 4.83

Display brightness for night operations 4.00 2.00 2.00 2.67

Window shading during day operations 7.50 7.00 7.00 7.17

Interior lighting during night operations 3.00 2.50 2.50 2.67

External lighting during night operations 2.50 2.50 2.50 2.50

Eye fatigue while driving 3.00 3.00 3.00 3.00

Eye fatigue while riding 3.00 2.50 2.50 2.67

Overall Average 3.79 3.29 3.29 3.46
57 

used the bubble extensively for observations and photographic archiving of geological points of 

interest (Figure 33). 

 

Figure 33- Geologist using lower bubble to photograph a geologic item of interest (left). The SPR’s panoramic 

front window enhanced driving and scientific observations (right).

Other highly acceptable ratings included the external and interior lighting during night 

operations, and display brightness for night operations. Participants found the interior cabin 

lighting (light-emitting diodes) comfortable for their sleep stations, and they found the lower 

floor lights extremely helpful for night driving operations (Figure 34). 

Figure 34 – Night operations using the interior and exterior lighting of the SPR.

 
58 

3.5.4 SUIT PORT HUMAN FACTORS

The human factors evaluation of the suit ports and suit port interfaces was a stand-alone test 

hypothesis and results are in Section 3.4. 

3.5.5 HABITABILITY OF CREW ACCOMMODATIONS

During the 3-day traverse, participants spent 64 hours and 24 minutes in the SPR vehicle and 

performing EVAs from the SPR (see Section 3.6.2 for detailed time breakdown). Evaluation of 

crew accommodations habitability was separated into i) daily operations within the vehicle, ii) 

sleep and general habitation, and iii) cockpit seating. 

Habitability of Crew Accommodations: Daily Operations

Subjects rated 19 different aspects of SPR habitability during daily operations using the 

acceptability scale defined in Section 2.3.5. The results (Table 12) show that the primary aspects 

in which the human factors were borderline (acceptability between 3 and 6) were stowage and 

waste disposal. Stowage issues had the most negative ratings by far, with size of and access to 

stowage being the most significant issues. These were followed by location of the stowage 

compartments and access to food stowage. Crew transfer bags (CTB) were used as stowage 

containers for personal items, food, exercise equipment, EVA equipment, hygiene and WCS 

products, mission supplies (such as pens, pencils, and flashlights), and trash collection supplies. 

Seven CTBs of various sizes were arranged either underneath the aisle and cockpit floor, or 

underneath the benches (Figure 35). 

Participants reported that CTBs needed to be packaged more efficiently for better utilization of 

the internal volume. For this field trial, products were placed in the bags without any 

compartmentalization of the items. CTBs were organized to some degree with respect to the 

articles inside (some were food CTBs, others EVA CTBs, and so on), and each CTB was 

numbered and labeled. However, the subjects were not familiar with the locations and contents 

of each CTB. In addition, the bags were rather large, and suggestions were to design smaller 

containers about the size of shoeboxes. Better access to the stowage containers was requested, as 

well as addition of stowage to the side hatch area. One suggestion was to create a soft wall locker 

where items could be placed for easier access and removal. For waste and trash management 

concerns, participants suggested designing an opening in one of the floor panels with a sealable 

flap to stow trash in a container under the floor or design a small manual trash compactor. 

 
59 

Table 12 – Acceptability ratings for SPR habitability during daily operations during 3-day traverse. 

Note: N=2. SA is situational awareness. Best = 1, Worst = 10.

 

Figure 35 – Two CTB stowage areas: under the bench (left, shown as the bench is raised behind a cockpit 

seat) and under the floor (right).

Volume for meal preparation, eating together, meal cleanup, general housekeeping, access to the 

hygiene area during normal operations, and waste containment system (WCS) privacy received 

some of the best ratings from participants. 

However, rating of the volume to deploy and stow the WCS, the ability to use the WCS during 

sleeping hours, and accessibility of the sink area were rated as needing minor improvements. 

SPR Daily OPS Tasks Day 1 Day 2 Day 3 Average

Access to food stowage 6.50 5.00 6.00 5.83

Volume for crew to prepare a meal 3.50 2.00 1.50 2.33

Volume for crew to eat together 3.00 2.00 1.50 2.17

Volume within SPR for meal cleanup 3.00 2.00 1.50 2.17

Accessibility to sink area for dispensing of water 5.00 5.50 3.50 4.67

Volume to deploy the WCS for use in SPR 3.50 3.00 2.50 3.00

Access to the hygiene area during normal crew OPS 3.50 3.00 2.00 2.83

Volume for using the WCS during sleeping hours 3.50 3.00 3.50 3.33

WCS area provided adequate privacy 3.00 2.50 3.00 2.83

Volume to stow WCS 4.00 2.50 3.50 3.33

Volume for general housekeeping activities 3.00 2.50 2.50 2.67

Volume for waste/trash disposal 4.50 4.50 5.50 4.83

Volume for waste/trash stowage 5.00 5.50 6.50 5.67

Location for daily trash collection 4.00 6.00 7.00 5.67

Access to stowage areas 6.00 5.50 6.50 6.00

Volume for personal stowage 5.50 4.50 5.50 5.17

Location of the stowage compartment within SPR 6.50 6.00 5.00 5.83

Size of the stowage compartments within SPR 6.00 6.00 6.00 6.00

Overall habitable living of the SPR 4.00 3.00 3.00 3.33

Overall Average 4.37 3.89 4.00 4.09
60 

Participants reported that the sleep station rear curtains, when attached together across the aisle 

in front of the WCS, provided inadequate space when using the WCS. They also noted that when 

the curtains were down in the sleep station position, they tended to fold down over the WCS as 

well, thus reducing the ability to properly use the WCS. To gain better access to the sink and 

water station in the vehicle, participants suggested replacing the current levers with longer levers 

and hoses to fill drink cups and food bags. 

Participants reported that over the 3-day mission the waste and trash accumulated quickly. 

Because of time constraints, the prototype vehicle did not include a dedicated waste and trash 

disposal system and the crew used large white plastic trash bags for disposal of the waste and 

trash. 

Habitability of Crew Accommodations: Sleep Stations and General Habitat

Subjects rated 12 different aspects of the habitability of SPR sleep stations and general habitat 

operations using the acceptability scale defined in Section 2.3.5. Results are shown in Table 13. 

Deployment and stowage of the sleep station were the only aspects that were rated Borderline. 

Participants indicated that the Velcro that attached the curtain sections together was difficult to 

match up, suggesting zippers as an alternative. Participants reported that deployment and 

stowage of sleep stations was easier with two persons. However, with more training, this could 

be done with only one person. Suggestions for redesigning deployment and stowage methods 

were to add stiffeners between the panels to make them easier for a single person to stow. 

Table 13 – Acceptability ratings for SPR sleep stations and general habitat during 3-day traverse. 

Note: N=2. SA is situational awareness. Best = 1, Worst = 10.

Participants indicated that although the layout of the sleep stations was good, personal stowage 

within the station needed improvement (described in Section 3.5.5). Better access to light 

switches and holders for personal items such as water, iPods, and pens was also desired. With 

SPR Sleep and General HAB Tasks Day 1 Day 2 Day 3 Average

Sleep station in the rover easily deployable 4.50 4.00 4.50 4.33

Volume for crew sleep station 2.50 2.50 2.00 2.33

Sleep station layout 3.50 2.50 3.00 3.00

Volume for personal privacy 2.50 2.50 3.00 2.67

Sleep quality while resting in rover 3.50 3.00 3.00 3.17

Sleep station in rover easily stowed 4.50 4.00 3.50 4.00

Volume for the rover habitat's workstation areas 3.00 3.00 3.00 3.00

Volume to limit cross-contamination 3.00 3.00 3.50 3.17

Volume for co-location of related functions/operations 3.00 3.00 4.00 3.33

Volume of SPR layout for a 3 day mission 2.00 2.00 1.50 1.83

Volume of SPR layout for a 14 day mission 2.00 2.00 1.50 1.83

Volume of SPR layout for a 30 day mission 2.00 4.00 3.50 3.17

Overall Average 3.00 2.96 3.00 2.99
61 

regard to the quality of comfort for sleep, participants reported the memory foam cushions were 

“very comfortable and made for a good night’s sleep.” 

Test participants, vehicle engineers, and scientists involved with the vehicle over the 2 weeks of 

testing commented that from the outside the SPR looked small; however, once inside and 

working, the majority reported the interior volume was “spacious and comfortable.” When asked 

what made the interior feel this way, they stated it was the color selection, textures of the fabric, 

and the panoramic windows in front of the vehicle. Participants reported that the cockpit and 

cabin were great, and the ability to fully stand up was the best quality. The multifunctional 

capability of the cabin area (for example, benches turned into beds) was also considered good 

and was relatively simple to change when needed. 

Habitability of Crew Accommodations: SPR Cockpit

Subjects rated eight different aspects of the habitability of the SPR cockpit using the 

acceptability scale defined in Section 2.3.5. Results are shown in Table 14. 

A wire for adjusting the seats broke during the mission and participants remarked that this 

mechanism needed to be more stable and robust for a seat adjustment system. Additionally, the 

crew requested that foot rests be added to the seats. Otherwise, the seats and cockpit were rated 

favorably, with participants particularly approving of the comfortable cushions and pleasing 

appearance (see Figure 11). 

Table 14 – Acceptability ratings for SPR cockpit during 3-day traverse. 

Overall Habitability of SPR 

Participants were asked to rate the acceptability of the overall SPR habitable volume and the 

overall acceptability of the SPR. Subjects were also asked whether or not they would recommend 

the SPR habitable configuration, overall. 

For the overall habitable volume of the SPR, participants rated the volume as acceptable (mean = 

3.17) with minor improvements to the stowage system desired for better efficiency and 

utilization of available space. Subjects commented that the overall volume of the cabin and 

cockpit was great, with the ability to fully stand up as one of the best qualities. 

Overall acceptability of the vehicle was seen as “acceptable–minor improvements desired” 

(mean = 3.33). The test crew indicated that there were good human factors in the design for 

p g y yf

SPR Seating Characteristics Day 1 Day 2 Day 3 Average

Comfortable cockpit seating for driving 3.50 3.00 3.00 3.17

Adjustability of cockpit seat 3.00 4.00 4.00 3.67

Stability of cockpit seat while driving 3.00 3.00 3.00 3.00

Foot and arm rest for cockpit seats 3.50 3.00 3.00 3.17

Height of cockpit seat 3.00 3.00 2.50 2.83

Width of cockpit seat 2.50 2.50 2.50 2.50

Depth of cockpit seat 3.00 2.50 2.50 2.67

Comfortable seating while doing OPS tasks 3.00 2.50 2.50 2.67

Overall Average 3.06 2.94 2.88 2.96

Note. N = 2.
living comfortably in the vehicle,

rearranging functions in the cabin

could have been used for persona

suggested a double side hatch opt

for docking SPR to SPR, or not li

provide more personal volume fo

Participants commented on sever

longer duration missions. These i

climbing in and out of the suit po

stowage, and crew dynamics. Wa

ability to dispense the waste and 

addressed. Personal preparation ti

resupply consumables was also a 

recommend the current SPR conf

Section 2.3.5) collected througho

duration of the 3-day traverse (Fi

Figure 36 – Subjective fatigue ratings

of each of the 3-day traverse

 

62 

le, such as the multifunctional aspects and simplic

bin. Between the bench and the exterior hatch was

nal stowage, such as a mounted locker system. Th

option for the vehicle (that is, a hatch on each side 

t limited to a single side for outpost docking), whi

 for each crewmember. 

eral factors that could cause issues for the crew, e

e included limited areas for personal hygiene, mus

 port, waste and trash management, workload in ge

aste and trash built up quickly over the 3-day mi

d trash at a reasonable rate to decrease crowding w

n time for an EVA mission was a concern and the 

 a key concern. However, both subjects indicated 

nfiguration for a 3-day mission. Subjective fatigu

hout the 3-day traverse showed no increase in fatig

(Figure 36). 

gs at the beginning (Pre) and end (Post) of 

licity of 

as space that 

The participants 

de of the vehicle 

hich would also 

, especially during 

uscle fatigue 

 getting to 

mission. The 

g will have to be 

he ability to 

ed they would 

igue ratings (see 

atigue over the 
63 

3.5.6 SPR EXERCISE DEVICE HUMAN FACTORS 

Upon completion of the 3-day SPR traverse, one subject completed an evaluation of the SPR 

exercise device. The subject unstowed the ergometer, completed a series of simulated aerobic 

and resistive exercises (actual exercising was not permitted during the field test without medical 

monitoring), then disassembled and stowed the equipment. The entire demonstration took about 

45 minutes. The participant rated the exercise equipment on 16 factors (Table 15) using the 

acceptability scale defined in Section 2.3.5. The time to set up and break down the equipment 

was also recorded (Table 16). 

All aspects of the exercise device human factors were within the acceptable range. The 

participant stated that the seat was simple to set up and was easily adjustable to his leg length; by 

moving the seat forward or aft by using the Velcro that held down the bench cushions, the 

participant was able to quickly adjust the seat and secure it. It was noted that the bench cushions 

could be used as a backrest, if needed. The participant felt there would be no problem exercising 

while the vehicle was moving. Figure 37 shows the participant simulating cycling and resistive 

exercise using the ergometer. 

It was noted that another resistive outlet on the front of the device down near the base would be 

useful and that alignment guides on the base plate of the ergometer to assist in getting the 

machine into the correct position would also be helpful. Other suggestions for redesign were to 

have a bigger display in the front of the device, to provide a straight bar for resistive exercising, 

and using a pulley system for resistive upper body exercises (see example in Figure 38). 
64 

Table 15 – Acceptability ratings for SPR exercise device. 

Table 16 – SPR exercise device set-up and break down times. 

SPR Exercise Demo Rating

Volume for 1 crew performing resistive exercise 2.00

Volume for 1 crew performing aerobic exercise 2.50

Design of ergometer to perform resistive exercise 2.00

Design of ergometer to perform aerobic exercise 3.00

Placement to secure equipment for resistive use 3.00

Placement to secure equipment for aerobic use 3.00

Accessibility to resistive exercise equipment 3.00

Accessibility to aerobic exercise equipment 3.00

Accessibility to workstations during resistive exercise 3.00

Accessibility to workstations during aerobic exercise 3.00

Stowage volume for exercise equipment 3.00

Comfort of the exercise seat 3.00

Stability of the exercise seat 2.00

Adjustability of the exercise seat 2.00

Setup of the exercise seat 2.00

Stowing of the exercise seat 2.00

Overall Average 2.59

Note. N = 1.

q p

Task Approximate Times

Unstow and Setup Time 10 mins

Seat Cushion Reconfig Time 4 mins 21 sec

Breakdown and Stow Time 2 mins
65 

 

Figure 37 – Participant demonstrating the SPR exercise device during simulated aerobic cycling and resistive 

exercise.

Figure 38 – Concept drawing of resistive upper body exercise with a bar and pulley system. 

 
66 

3.6 OTHER TEST OBJECTIVES

3.6.1 NIGHTTIME DRIVING AND EXPLORATION, MAPPING, AND GEOLOGICAL SAMPLE COLLECTION 

AND DOCUMENTATION TASKS 

One nighttime EVA lasting 25 minutes was 

completed during which one crewmember 

egressed the SPR via the suit port and performed 

a series of EVA tasks while the second 

crewmember provided support from inside the 

SPR (see Figure 34 and Figure 39). No nighttime 

EVAs were performed from the UPR. 

Illumination for the EVA crewmember was 

provided by lights on the helmet of the mockup 

EVA suit and flood lights mounted on the SPR. 

The illumination during nighttime EVA and 

driving was rated as acceptable using the same 

Acceptability Rating scale utilized in the other 

human factors evaluations. A Cooper-Harper 

rating of 4 for nighttime driving was reported 

indicating that moderate operator compensation 

was required to achieve the desired driving 

performance. The EVA crewmember 

successfully completed all geological sampling 

tasks. 

As reported in Section 3.5, subjects reported that 

the external and interior lighting during night 

operations was highly acceptable with the lower 

floor lights being extremely helpful for night 

driving operations. 

3.6.2 MEASURE PERFORMANCE METRICS DURING 1-DAY AND 3-DAY (SPR ONLY) EXPLORATION,

MAPPING, AND GEOLOGICAL TRAVERSES

Performance metrics were collected for all UPR and SPR traverses throughout the field test. A 

summary of the metrics for each of the traverse days is shown in Table 17 and a graphical 

comparison of the crew time metrics for 1-day UPR and SPR traverses is shown in Figure 40. 

The average speed in motion of the vehicles is given to present an accurate notion of average 

speed; it does not include idle time because of EVA events. Figure 41 shows traverse paths of 

the SPR over the 3 day period, as denoted by the red (day one), green (day 2) and yellow (day 3) 

paths. 

Figure 39- Nighttime EVA performed by one 

geologist with support from inside SPR. 
67 

For the purposes of recording crew time classifications subjects verbally communicated to the 

CAPCOM when tasks were started and finished. Times were recorded using data sheets and the 

duration of each task was calculated. EVA Overhead was defined as tasks required before, 

during and after EVAs such as SPR egress, suit purge, tool retrieval, tool and sample stowage, 

and SPR ingress, which are necessary when performing EVAs but do not themselves directly 

accomplish any of the EVA objectives. 

Table 17 – Performance metrics for UPR and SPR traverses at DRATS 2008. 

EVA boots-on-surface suit time is generally the time during which most scientific productivity is 

being achieved whereas time spent inside the EVA suit during vehicle ingress and egress is 

nonproductive EVA time. By comparing EVA suit time to EVA boots-on-surface suit time, the 

efficiency with which EVA suit time is used may be quantified. As shown in Table 17, 

productive EVA time represented an average of only 28% of total EVA time during UPR 

traverses compared with 79% during equivalent 1-day traverses using the SPR. 
Figure 40 - Comparison of crew time

Figure 41 – Path of the SPR d

68 

me breakdown for 1-day UPR and SPR traverses.

 during the 3-day traverse (red: day 1, green: day 2, yellow: day 3).
69 

The number of EVAs performed during traverses affects the consumables lost during ingress and 

egress operations, the energy required to operate gas reclaim pumps (with airlock) and the 

number of cycles on suit ports or the Mobile Habitat airlock. The SPR traverses planned by the 

Science Team and executed by the crews at DRATS 2008 averaged almost 5 EVAs per person 

per day. This high frequency of EVAs led to the total EVA overhead per traverse day being only 

slightly less than with the UPR traverses; however it was the ability to use EVA only when 

required that enabled the 62% reduction in EVA time while achieving 57% greater performance, 

as described in Section 3.1. 

Over the 4 days of SPR traverses a total of 38 SPR egress/ingress cycles were performed. 

However, not all of these vehicle egress/ingress cycles were completed using the suit ports 

because of limitations of the Mockup EVA suits. Although intended to be lightweight, the fully 

instrumented EVA suits were too heavy for subjects to wear for all EVAs without risking 

unacceptable levels of exertion and/or discomfort. In accordance with the test plan (see Section 

2.2.2.2), subjects were free to transition to the lightweight backpacks at any time and were 

required to use the lightweight backpack or terminate the test when reporting a discomfort rating 

> 7 (on Corlett and Bishop 10-point Discomfort scale) for two consecutive recording periods 

during suited testing. 

During the four 1-day traverses, participants in the mockup EVA suits lasted about 5 hours 30 

minutes in the UPR configuration before switching to lightweight backpack alternatives. By 

comparison, the same subjects during the SPR traverses lasted about 7 hours and 30 minutes 

before switching to backpacks. Because the lightweight backpacks cannot be used with the suit 

ports, subjects would egress the SPR via the side hatch and don the lightweight backpack. In all 

cases, the times associated with suit port egress procedures were followed to ensure that vehicle 

timelines were not biased by the side hatch egress/ingress cycles. Measured task time data from 

side hatch egress/ingress cycles were not included in any subsequent data analysis. The egress 

and ingress durations for the four 1-day SPR traverses, excluding side hatch egresses as 

described, are shown in Figure 42. 

 
Figur

During the Arizona desert analog

important to note that these numb

because the concept of operations

with a series of short duration (1-

test. The relatively local explorat

of those which would be perform

Although not included in this rep

both provide a baseline of operati

chassis system provided data that

For example, the day one traverse

consisted of fine dust-like particle

one traverse was 10.5%. The day

rolling resistance during this perio

the difference in power required t

70 

ure 42 - SPR Egress and Ingress Durations.

og tests, the SPR travelled 148 kilometers over 14

mbers should not be generalized to a 14-day longons and the traverse planning will differ significan

-3 days) and short range (< 6km) traverses perfo

ration traverses conducted during this test are like

rmed early in the lunar architecture. 

eport, data was collected on all subsystems for use

ration and to improve upon the current SPR config

hat illustrates how the vehicle operated in the analo

rse occurred mainly on a ranch road that was flat, 

icles. The average rolling resistance during this pe

ay 2 traverse occurred on a more firm, rocky surfa

eriod of the day 2 traverse was 8.0%. These measu

d to drive the SPR on dissimilar terrains. 

14 days. It is 

-range traverse 

antly compared 

rformed during this 

kely representative 

use by engineers to 

figuration. The 

alog environment. 

at, soft and 

period of the day 

rface. The average 

asurements show 
71 

4.0 CONCLUSIONS

1) Productivity achieved during 1-day exploration, mapping, and geological traverses using 

the Small Pressurized Rover (SPR) was 57% greater than the productivity achieved 

during Unpressurized Rover (UPR) traverses, with 61% less EVA suit time. Excellent 

visibility from inside the SPR combined with the ability to rapidly egress and ingress the 

SPR via suit ports enabled utilization of high-frequency short-duration EVAs, including 

single-person EVAs performed with IV support from inside the SPR. 

2) Range achieved during 1-day exploration, mapping, and geological traverses in the SPR 

was not significantly greater than during 1-day UPR traverses because of 

communications constraints at the field test site. Average distance driven during 1-day 

exploration, mapping, and geological traverses in the SPR was 4.3 km (31%) greater than 

during 1-day UPR traverses primarily because the 8-hr consumables limit on UPR 

traverses reduces the available driving time as compared with SPR traverses. 

3) Subjective assessments of contextual observations from inside an SPR were 

approximately equal to walking shirtsleeve. A controlled comparison of contextual 

observations from inside the SPR with contextual observations from inside an EVA suit 

was not performed but it is anticipated that the added mass, limited mobility and reduced 

field of view in an EVA suit will make the SPR equal to or better than the EVA suit for 

making contextual observations. 

4) Human interfaces to the SPR suit ports and alignment guides were acceptable as assessed 

by human factors metrics. Several modifications were identified to improve human 

factors and reliability in subsequent SPR suit port designs. 

5) The human factors and crew accommodations within the SPR were acceptable to support 

a 3-day exploration, mapping, and geological traverse. Multiple modifications were 

identified to improve human factors and crew accommodations in subsequent SPR 

designs. 

6) Nighttime driving and exploration, mapping, and geological sample collection and 

documentation tasks were performed successfully using the SPR with acceptable human 

factors. 

7) Performance metrics were recorded during 1-day and 3-day (SPR only) exploration, 

mapping, and geological traverses. These metrics, combined with metrics from 

subsequent field test activities, will be used in the development of models by the Lunar 

Surface Systems Project and the Human Research Program. 
72 

5.0 REFERENCES 

Bedford, T. (1936) The warmth factor in comfort at work. MRC Industrial Health Board Report 

No. 76, London HMSO. 

Borg, G.A. (1982) Psychophysical bases of perceived exertion. Medicine and Science in Sports 

and Exercise, 14(5), 377-381. 

Braukus M, Dickey B, Humphries K. “NASA Reveals Global Exploration Strategy and Lunar 

Architecture.” NASA. December 04, 2006. Web. June 15, 2010. 

<http://www.nasa.gov/home/hqnews/2006/dec/HQ_06361_ESMD_Lunar_Architecture.html> 

Corlett, E.N. and Bishop, R.P.A. (1976). A technique for assessing postural discomfort. 

Ergonomics, 19(2), 175-182. 

Haughton Mars Project. 24 August 2010. National Aeronautics and Space Administration. 15 

June 2010. 

http://www.nasa.gov/exploration/humanresearch/analogs/research_info_analoghaughton.html

Preliminary Report of the Small Pressurized Rover (SPR), IHMC Technical Report 01-2008, 

Submitted to NASA Exploration Systems Mission Directorate, (February 2008). 

Litaker, H. (2008). Small Pressurized Rover (SPR) Three Day Desert Trial: A Human Factors 

Assessment. Internal NASA Document. 

Schierholz S, Hautaluoma G, Dean B, Humphries K, Prucey R. “NASA Tests Lunar Robots and 

Spacesuits on Earthly Moonscape.” NASA. June 13, 2008. Web. June 15, 2010. < 

http://www.nasa.gov/home/hqnews/2008/jun/HQ_08149_Moses_Lake.html > 

6.0 ACKNOWLEDGEMENTS

The authors would like to acknowledge the enthusiasm, dedication and excellence demonstrated 

by the entire Desert RATS Team throughout the 2008 campaign. And for their contributions to 

the preparation of this report, the authors acknowledge and thank Dale Ward and Jennifer 

Jadwick. 
73 

Figure 43 – Desert-RATS 2008 Team (many other team-members not shown). 

7.0 APPENDICES

APPENDIX A: RATIONALE FOR USE OF ANALOG TEST SITE

FACILITIES AND PERFORMANCE SITE

Based on analyses performed during the LAT-2 study, science and exploration EVA could 

constitute more than 90% of total EVA time over a 10 year lunar architecture. A geologically 

relevant and scale-appropriate test site (such as Devon Island or Black Point Lava Flow) is 

essential when testing productivity, performance and human factors during exploration, 

mapping, and geological traverses. 

Test subject training and dry-run activities were conducted at the JSC Rock Yard and in the 

Space Vehicle Mockup Facility (B9) at JSC. Testing occurred at the Black Point Lava Flow test 

site, about 40 miles north of Flagstaff, Arizona (Figure 46). 

Detailed side-by-side comparisons of the SPR’s and UPR’s theoretical performance, productivity 

and safety capabilities and constraints have been performed and previously documented during 
74 

the LAT-2 and CxAT_Lunar projects. This test was designed to validate previous findings and to 

add fidelity and realism to the comparisons, particularly with respect to SPR IVA productivity 

and human factors. Based on these objectives, the primary test site requirements with respect to 

EVA and Surface Operations are discussed and detailed below. 

GEOLOGICALLY RELEVANT TERRAIN

Geologically relevant terrain was necessary to assess the ability of subjects to make geological 

contextual observations from inside the SPR compared with the UPR. It was also required to 

enable estimation of SPR performance and productivity metrics such as number of EVAs, 

maximum separation of EVA astronaut and SPR, boots-on-surface EVA time and average drive 

speed, all of which are largely terrain dependent. To the extent that performance metrics can be 

accurately estimated based on realistic field tests, the accuracy of estimated ranges, masses, 

dimensions and power, energy storage and consumables requirements produced by existing 

mobile surface systems models will also be improved. 

The Black Point Lava Flow test site includes a wide variety of surface features with geological 

relevance. The geological features and terrain particularly along the edge of the lava flow 

provided many opportunities to evaluate the IVA and EVA science and exploration capabilities 

of the SPR during exploration, mapping, and geological traverses. Additional information on the 

geology of the Black Point Lava Flow test site is included in Appendix D. 

Figure 44 – View of lava flow escarpment ~4 km (2.5 miles) from proposed base camp location. 
75 

Figure 45 – Examples of geological sites of interest at Black Point Lava Flow. 

SCALE-APPROPRIATE TEST SITE 

Theoretical UPR and SPR sorties developed during the LAT-2 and CxAT_Lunar studies 

involved driven distances of up to 40 km per day. There are several reasons that long-distance 

sorties must be performed during field testing, and they relate to the anticipated benefits of SPRbased traverses as compared with UPR-based traverses. 

In a UPR, exploration traverses are limited to 8 hours, which is the maximum time that can be 

spent in an EVA suit. The capability to perform exploration traverses lasting many days is 

among the most significant benefits of the SPR concept as compared with a UPR alternative. 

SPRs also offer greater boots-on-surface EVA time during which to perform science tasks 

because of the EVA time that is saved by driving to and from exploration sites inside the 

shirtsleeve SPR environment. Furthermore, the shirtsleeve environment inside the SPR when 

driving between EVA sites potentially enables more productive use of crew time than is possible 

when performing the same drives on a UPR. 

Evaluating the extent to which these perceived benefits are realized required that detailed and 

accurate exploration, mapping, and geological traverses were planned and executed on scales 

comparable to those which are anticipated during actual lunar traverses and that translation 

distances and times were not artificially constrained. 
76 

The size of the Black Point Lava Flow site and the abundance of exploration, mapping, and 

geological features would potentially enable extended range exploration, mapping, and 

geological SPR traverses (potentially > 100km+ driven distance with 7 -14 days of operational 

time). 

Figure 46 – Test Site: Black Point Lava Flow, Arizona. 

Base Camp

Gravel Road – 1 mile long 
77 

UPR AND SPR NEGOTIABLE TERRAIN CONDITIONS:

The slopes, soil mechanics, surface properties and existing terrain features of the test site were 

required to be negotiable by the UPR and SPR vehicles. The slopes from the top to the base of 

the Black Point lava flow vary from very slight (approx 6o

) to vertical. Terrain conditions vary 

from powdery sand with minimum to significant vegetation (< 12”) to harder packed ground 

with numerous small and medium-sized rocks and minimal vegetation (Figure 47 – Figure 49). 

The base camp location was on top of the lava flow on a hard packed surface (193 kPa / 28 PSI 

load bearing capability) artificially created next to a gravel quarry. Vegetation was minimal in 

the base camp area and the nearby ash and gravel quarry but became denser in some locations. 

Figure 47 – Test site base camp location. 
78 

Figure 48 – Looking south along the edge of Black Point Lava Flow; note varying slopes, varied 

geology, and representative vegetation. 

Figure 49 – Example of slope variation, geological features and moderate vegetation at edge of Black 

Point Lava Flow. 
79 

APPENDIX B: BLACK POINT LAVA FLOW SCIENCE TRACEABILITY MATRIX Table 18 – Black Point Lava Flow Field Test: Science Traceability Matrix.Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

Volcanics Black Point Lava Flow 1 What is the 

absolute age of the BPLF? 

Dating lunar volcanic events 

Radiometric dating of a sample representative of the BPLF 

EVA Station A Collect 2 fresh (edge of flow) hand samples from the BPLF 

Positioning To+ Camera + RocHammer (igneous) + Sample Bag 

1 What is the 

composition (mineralogy, chemistry) of the BPLF? 

Composition of lunar volcanic materials 

Mineralogy and geochemistry of a representative sample of the BPLF

EVA Station A Collect 2 fresh (edge of flow) hand samples from the BPLF 

Positioning To+ Camera + RocHammer (igneous) + Sample Bag 
80 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

2 Does the BPLF 

present spatial variations in composition? 

Spatial variation in composition of materials from a single volcanic event 

Mineralogy and geochemistry of a suite of samples collected along the length of the BPLF. 

EVA Stations A, B, C. Collect 2 fresh (edge of flow) hand samples at each of at least 3 locations 1 km apart along the length of the BPLF 

Positioning To+ Camera + RocHammer (igneous) + 3 Sample Bags 

1 Target of Opportunity 

Does the BPLF contain large xenoliths? 

Search for lunar mantle xenoliths in lunar volcanic materials 

Look out for any occurrence of large xenoliths along length of the BPLF 

EVA Stations X Collect 2 fresh hand samples from at least one location if encountered 

Positioning To+ Camera + RHammer (igneous) + 3 Sample Bags 

2 What petrologic 

textures does the BPLF present? Any lateral variations? 

Petrologic textures of lunar volcanic materials 

Petrology of a suite of samples collected along the length of the BPLF. 

EVA Stations X Collect 2 fresh hand samples of any instance of significant lateral petrologic variation along the length of the BPLF 

Positioning To+ Camera + Rhammer (igne+ 10 Sample b
81 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

2 Target of Opportunity 

What petrologic textures does the BPLF present? Any vertical variations? 

Petrologic textures of lunar volcanic materials 

Petrology of a suite of samples collected along one or more vertical sections of the BPLF 

EVA Stations X If vertical variations in rock texture are found: Collect at least 2 hand samples at each of 3 levels along a vertical section of the BPLF. Repeat at other vertical section locations along the length of the BPLF if needed. 

Positioning To+ Camera + RHammer (igneous) + 3 Sample Bags 
82 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

2 What 

morphologic and structural features does the BPLF present? (Lava Tubes, Collapse Features, Sags, Faults, Joints, etc.) 

Morphologic and Structural features associated with lunar volcanic units 

Morphologic and Structural observations and analysis of the BPLF 

EVA Stations X Document any significant structural features of the BPLF. EVA Station S Examine sag associated with high albedo feature on surface of BPLF 2 km south of camp. 

Positioning To+ Camera 

1 What features 

are present in the apparent “Source Area” of the BPLF? 

Investigation of “Source Areas” of lunar volcanism 

Geologic characterization of “Source Area” of the BPLF 

EVA Station Z Document and sample materials from the apparent “Source Area” of the BPLF. 

Positioning To+ Camera + 1Sample Bags 
83 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

1 What is the 

geologic relationship between the BPLF and underlying lithologic units? What is the geologic and evolutionary history nature of these underlying units? 

Investigations of the geologic relationship between lunar volcanic flows and underlying lithologic units. 

Geologic characterization of the contact between the BPLF and underlying lithologic units. 

EVA Stations A to C Follow contact between BPLF and underlying lithologic units. Note dip and strike of any underlying layered units. 

Positioning To+ Camera + 1Sample Bags 

2 What is the 

nature of the High Albedo Features on the top surface of the BPLF? Do the albedo features represent eolian deposits? 

Investigation of discrete and/or anomalous albedo features on the Moon 

Geologic characterization of the High Albedo features on top of the BPLF. 

EVA Station S Document and sample materials from the High Albedo Units on top of the BPLF. 

Positioning To+ Camera + 3 Sample Bags 
84 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

Other Lava Flows and Volcanic Features 2 What is the 

absolute age of Other Lava Flows and Volcanic Features near the BPLF? 

Dating lunar volcanic events 

Radiometric dating of samples representative of the Other Lava Flows and Volcanic Features near the BPLF 

EVA Stations D, E, F Collect 2 fresh hand samples from the Other Lava Flows and Volcanic Features near the BPLF 

Positioning To+ Camera + RocHammer (ignerocks)+SamplBag 

2 What is the 

composition (mineralogy, chemistry) of the Other Lava Flows and Volcanic Features near the BPLF? 

Composition of lunar volcanic materials 

Mineralogy and geochemistry of a representative samples of the Other Lava Flows and Volcanic Features near the BPLF 

EVA Stations D, E, F Collect 2 fresh hand samples from the Other Lava Flows and Volcanic Features near the BPLF 

Positioning To+ Camera + RocHammer (ignerocks) + SampBag 
85 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

3 Target of Opportunity 

Do the Other Lava Flows and Volcanic Features near the BPLF present spatial variations in composition? 

Spatial variation in composition of materials from a single volcanic event 

Mineralogy and geochemistry of a suite of samples collected along the length of a selected Lava Flow or Volcanic Feature near the BPLF. 

EVA Stations D, E, F. Collect 2 fresh hand samples at each of at least 3 locations 1 km apart along the length of a selected Lava Flow near the BPLF and/or from distinct Volcanic Features near the BPLF 

Positioning To+ Camera + RocHammer (ignerocks) + 3 SamBags 

1 Target of Opportunity 

Do the Other Lava Flows near the BPLF contain large xenoliths? 

Search for lunar mantle xenoliths in lunar volcanic materials 

Look out for any occurrence of large xenoliths along length of Other Lava Flows near the BPLF 

EVA Stations X Collect 2 fresh hand samples from at least one location if encountered 

Positioning To+ Camera + RHammer (ignerocks) + 3 SamBags 
86 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

3 What petrologic 

textures do the Other Lava Flows near the BPLF present? Any lateral variations? 

Petrologic textures of lunar volcanic materials 

Petrology of a suite of samples collected along the length of a selected Lava Flow near the BPLF. 

EVA Stations X Collect 2 fresh hand samples of each instance of significant lateral petrologic variation along the length of a selected Lava Flow near the BPLF 

Positioning To+ Camera + Rhammer (ignerocks) + 10 Sample bags 
87 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

3 Target of Opportunity Target of Opportunity 

What petrologic textures do the Other Lava Flows and Volcanic Features near the BPLF present? Any vertical variations? 

Petrologic textures of lunar volcanic materials 

Petrology of a suite of samples collected along one or more vertical sections of a selected Lava Flow near the BPLF 

EVA Stations X If vertical variations in rock texture are encountered: Collect at least 2 hand samples at each of 3 levels along a vertical section of a selected Lava Flow near the BPLF. Repeat at other vertical section locations along the length of the selected Lava Flow near the BPLF if needed. 

Positioning To+ Camera + RHammer (ignerocks) + 3 SamBags 
88 

Priority 1=high 3=low 

Science Question 

Relevance to the Moon 

Observation(s) & Analysis Needed 

Traverse Task(s) Traverse Too

Needed 

2 What 

morphologic and structural features do the Other Lava Flows and Volcanic Features near the BPLF present? (Cinder Cones, Vents, Lava Tubes, Collapse Features, Sags, Faults, Joints, etc.) 

Morphologic and Structural features associated with lunar volcanic units 

Morphologic and Structural observations and analysis of the Other Lava Flows and Volcanic features near the BPLF 

EVA Stations X Document any significant structural features of the Other Lava Flows and Volcanic Features near the BPLF. 

Positioning To+ Camera 
89 

Other Geologic Units and Features Marbled Terrain North of Flow 1 What is the 

nature and evolutionary history of the Marbled Albedo Unit? 

General lunar geology science operations. Lunar regolith science operations. 

Systematic geologic observations, characterization, and sample analysis. 

EVA Stations A, B, C, G, H. 

Positioning T+ Camera + Rock Hamme(SedimentaryTrenching To+ 8 Sample Bags 

3 What is the 

nature and evolutionary history of the dissection in the Dissected Unit? 

Lunar rill science operations. 

Systematic geologic observations, characterization, and sample analysis. 

EVA Station J Positioning T

+ Camera + Rock Hamme(SedimentaryTrenching To+ 4 Sample Bags 
90 

3 What is the 

nature and evolutionary history of the Non-Dissected Transitional Unit? 

General lunar geology science operations. Lunar regolith science operations. 

Systematic geologic observations, characterization, and sample analysis. 

EVA Stations J and K 

Positioning T+ Camera + Rock Hamme(SedimentaryTrenching To+ 4 Sample Bags 

2 What is the 

nature and evolutionary history of the Knobby Unit? 

Lunar hummocky terrain science operations.

Systematic geologic observations, characterization, and sample analysis. 

EVA Station K Positioning T

+ Camera + Rock Hamme(SedimentaryTrenching To+ 2 Sample Bags 
91 

Layered Terrain NE of ( “Below”) Scarp2 What is the 

nature and evolutionary history of the Layered Unit Below 

General lunar geology science operations. Lunar regolith science operations. 

Systematic geologic observations, characterization, and sample analysis. 

EVA Station L Positioning T

+ Camera + Rock Hamme(SedimentaryTrenching To+ 4 Sample Bags 

Scarp 1 What is the 

nature and evolutionary history of the Scarp separating the Marbled Terrain North of the Flowand the Layered Unit NE of the Scarp? 

Lunar tectonics science operations. Lunar wrinkle ridge science operations. 

Morphologic and structural observations and analysis. 

EVA Station L Positioning T

+ Camera 
92 

Marbled Terrain South of Flow 2 What is the 

nature and evolutionary history of the Marbled Unit South of the Flow. 

General lunar geology science operations. 

Systematic geologic observations, characterization, and sample analysis. 

EVA Station T Positioning T

+ Camera + Rock Hamme(SedimentaryTrenching To+ 2 Sample Bags 

Other Albedo Features 3. Target of Opportunity

What is the nature and evolutionary history of the discrete and/or anomalous albedo features near the BPLF? 

Investigation of discrete and/or anomalous albedo features on the Moon. 

Geologic characterization and analysis of discrete/anaomalous albedo features near the BPLF. 

EVA Stations A to C. 

Positioning T+ Camera + Rock Hamme(SedimentaryTrenching To+ 12 Sample Bags 
93 

APPENDIX C: FIELD GEOLOGIST FEEDBACK ON SPR CONTEXTUAL 

OBSERVATION CAPABILITY

Field Geologist #1 

Rating: 2.5 

Overall Design: Windows presented an excellent view forward and to side for 10's of feet. 

Mobility: The ability to get close when the terrain was suitable, was remarkable. View was clear. 

I could get within inches of the rock. Could really see rock details. 

Cameras and Sensors: Did not use cameras and sensors. 

Other: I think this is an incredible vehicle to scout a possible EVA and plan collection sites in 

advance and make the traverse much more focused. 

Ability to observe across sufficient scales and/or fields of view: It was easy to move from the cm 

scale to the meter scale to the km scale and relate features to one another. It was comfortable to 

sit back and absorb the whole scene in front of you and synthesize your observations. 

Ability to consider and communicate multiple working hypotheses on the fly: My mind usually 

soaks in the observations for a considerable time before I start drawing conclusions, but I do 

have a steady flow of ideas I am considering all the time. 

_______________ 

Field Geologist #2 

Rating: 3.0 

Overall Design: Windows were very good for observing far field (seated view) and near (bubble) 

view. My only comment for improvement would be better ergonomic space between seats to 

access bubble view. The environment was very comfortable -- some heat on legs via sunny 

window while seated, but otherwise very, very nice. 

Mobility: The mobility was good. Approach to rocks was possible and made better with 

lowering vehicle and bubble view while lowered. Could not get as close as a human to cliff face 

because of boulders in front, but view was adequate and we could get as close to ground clasts, 

maybe closer considering pack blocks my human ability to bend over. We did get stuck for a 

couple of minutes. 

Cameras and Sensors: The camera worked well; we took one image of the caprock. Sensors 

seemed to work well also. 

Other: Very comfortable, little to no human exertion; good way to cover a lot of terrain with 

adequate access to rocks. 

Ability to observe across sufficient scales and/or fields of view: The vehicle compared very well 

to human walking in far and near field. The only difference was the vehicle's inability to reach 

cliffs because of obstructing boulders in front. So far and near field was equivalent. At cliff face 

the vehicle was limited. 
94 

Ability to consider and communicate multiple working hypotheses on the fly: The only difference 

is that a human could walk a bit faster and closer to red rock cliff -- perhaps observing rock 

geometries and contacts that would help in interpretation process. However, my observations 

did not change, nor did my interpretations using the vehicle, so the vehicle compared well and 

was shirtsleeve equivalent. 

_______________ 

Field Geologist #3 

Rating: 3.0 

Overall Design: Windows provide excellent forward-looking views of both the horizon and 

ground within inches of the vehicle. The environment is cool and controlled. This probably 

makes a difference over long durations; it was not important during a 30-minute test. 

Mobility: Fine. 

Cameras and Sensors: Did not use cameras and sensors 

Other: I think this is an incredible vehicle to scout a possible EVA and plan collection sites in 

advance and make the traverse much more focused 

Ability to observe across sufficient scales and/or fields of view: I was able to evaluate models of 

regional topography and test them with outcrop and rock-scale observations. 

Ability to consider and communicate multiple working hypotheses on the fly: Yes, this was 

possible (that is, nature of slope between red-colored bedrock bench and basalt bench above). 

_______________ 

Field Geologist #4 

Rating: 3.0 

Overall Design: Windows provide an impressive view of the surroundings: greater than 180 

degrees. Peripheral vision is nice, although the best feature of the windows is that they wrap 

around the bottom of the vehicle. This low view allows closer viewing of the ground and rocks 

than you would have walking. This is a huge geological advantage while driving. The vehicle is 

very comfortable and the ease of conversation provides lots of opportunity for discussion and 

collaboration during decision making and working through scientific ideas. The bubble window 

is a nice addition for looking up close. Might be nice to have more room at the front windows; 

being able to fold a seat up and sit or kneel on the floor of the vehicle would be awesome! 

Mobility: Really great... smooth ride that encourages doing observations while traveling. The 

ability to turn easily in place enables relatively quick views of the surrounding environment. I 

was surprised at how close to the sandstone outcrop we could get. Mobility is really only limited 

when it comes to getting to outcrops at the top of steep slopes with lots of large rocks and 

boulders. 

Cameras and Sensors: Did not use cameras and sensors 

Other: The need for EVAs for doing geology will never be eliminated, however, this vehicle 

enables and encourages excellent geologic observations at an impressive spread of scales. 
95 

Ability to observe across sufficient scales and/or fields of view: This vehicle allows observations 

of cm to km scale features. This allows the observer to build up an adequate initial 

understanding of geologic context. 

Ability to consider and communicate multiple working hypotheses on the fly: Yes, the 

comfortable interior of the vehicle will allow easy conversation between the crewmembers, 

which is likely to improve the quality of the field science. The context that can be gained in the 

vehicle will allow planned EVAs to be more focused and efficient, which will allow for a better 

investigation of multiple hypotheses. 

APPENDIX D: SCIENCE TEAM REPORT AND COMMENTS

UPR/SPR FIELD TESTS 

Flagstaff, AZ 

Oct.18-31 

SCIENCE EVALUATION: 

BACKGROUND 

INTRODUCTION: 

 The UPR/SPR field tests in the Black Point Lava Flow area, some 40 km N of Flagstaff, 

AZ, were primarily intended to evaluate the (lunar) surface mobility afforded by unpressurized 

(UPR) and pressurized (SPR) rovers, the latter critically depending on innovative suit port 

concepts for efficient egress and ingress. Predetermined test objectives and time lines were 

implemented remotely via trailer-housed mission control; the latter included a science team to 

monitor the geologic observations and sampling activities. The entire campaign was thus 

characterized by a very high degree of fidelity and realism relative to anticipated lunar surface 

operations. 

 This report summarizes the first order impressions of the science team regarding the 

utility of the tests. Time did not permit to produce a summary evaluation by the entire team in 

real time. Instead, the members of the science team were asked to individually compose their 

impressions, both positive and negative, on no more than two pages. This brief “background” 

document is intended to provide some general introduction for these evaluations, all part of this 

document, hopefully reducing wasteful introductions and redundancies in individual reports. 

SITE GEOLOGY 

 The Black Point Lava Flow and its surroundings were recognized during the Apollo era as 

highly suitable analog for the development of lunar surface exploration activities; as a 

consequence, a detailed geologic map was produced by USGS, Flagstaff. The latter was recently 

augmented and expanded by M. Chapman, USGS, Flagstaff, to specifically support the present 

Human Robotic Systems (HRS) activities; Chapman was thus the resident local expert during the 

2008 HRS tests. 
96 

 The major geologic formations of interest were the Black Point Lava Flow and its substrate, 

the Moenkopi Formation. The latter is of Triassic age (some 220 to 240 MY old) and reflects a 

series of diverse sediments ranging in grain size from clay-rich mudstone deposits to sand-rich 

strata, some finely bedded at centimeter scales and easily eroded, others of more massive and 

indurated character, up to 5 meters thick, forming prominent cliffs and ledges that can be traced 

for kilometers in lateral continuity. A wide variety of sedimentary structures, such as cross 

bedding, pebble horizons, ripple marks, etc., are readily observed in the field, indicating an 

estuarine environment akin to Louisiana’s present day Mississippi delta. Outcrops of these 

Moenkopi (MK) sediments are common in the area, allowing the collection of samples within 

stratigraphic context. 

 In contrast, the Black Point Lava Flow (BPLF) is a relatively recent feature, some 2.4 MY 

old; it is part of the regional “San Francisco Volcanic Field” that produced a number of well 

known basalt flows, some older, some younger than BPLF. The BPLF is more than 10 km long 

and in places as wide as 5 km; its actual source is buried by younger flows to the south of the test 

site. The thickness of the flow is highly variable, as it flowed and ponded in local topographic 

lows of an eroded surface in the MK formation. Most of the test traverses ranged along the 

exposed edges of the flow where basalt thicknesses are measured in a few meters. These 

exposures reveal a wide variety of basalt textures at scales < 1 m, ranging from dense to highly 

porous basalts, some displaying flow banding and lineation of vesicles, others more massive and 

vuggy; most basalts cooled sufficiently fast to yield “aphanitic” textures, implying that their 

component minerals are so small that they cannot be resolved by the unaided eye; on occasion 

cooling rates were sufficiently slow, however, to allow for millimeter size crystals that could be 

recognized in the field. Collectively, these textures suggest that the solidifying crust of the basalt 

flow was repeatedly broken and reincorporated into the viscous flow, thereby preserving a wide 

variety of textures and cooling phenomena in close juxtaposition. 

TRAVERSE PLANNING 

 Traverse planning occurred in two discrete phases: 

1) Photogeologic interpretation and prioritization of science objectives 

2) Detailed traverse routes, station objectives, and time lines. 

Re.1) The entire Science Team convened for 1 day to interpret the local geology from an aerial 

photograph at some 10 m resolution (see Figure 1). A topographic map was available as well and 

supported some of the interpretations. No field knowledge was allowed during this activity. The 

lava flow was readily observed and mapped, as was the sedimentary unit, yet its exact nature 

could not be discerned. The pre-mission photogeologic map produced by the science team is 

attached as Figure 2. A number of science considerations, too detailed for this report, identified 

the basalt flow as the highest priority objective, followed by the “Marbeled Unit” of poorly 

defined origin (and that turned out to be the MK sediments). Additional geologic units, such as 

the “channeled” and “chaotic unit” were differentiated and mapped as well, with both deemed of 

relatively low priority. 

Re.2) Detailed traverse planning was conducted by a sub-group of the science team as it involved 

almost daily interaction with evolving operational constraints, such as total duration of each 
97 

EVA, available range of communications, expected rover speed, detailed time-lines for vehicle 

egress and ingress, including depressurization, local “logistics” related to trafficability such as 

fence lines and roads. These detailed traverse plans were then distilled into cuff-check lists for 

the crew and other operational products for the back room; they also formed the basis for the 

quantitative pre-mission and post-mission evaluations of both UPR and SPR. The detailed 

duration for science activities during a crew’s workday was provided to the traverse planners by 

JSC-CB; the latter was also responsible for all other activities (and constraints) that were 

unrelated to science, and that needed to be accounted for during a full 15 hour crew day. 

A total of 4 individual traverses were planned: a) “1 Day UPR”; actually some 6:30 hrs duration; 

b) “1 Day SPR” (actually: 9:30 hrs); both crews A and B each conducted identical UPR and 1-

day SPR traverses for meaningful comparisons of UPR and SPR; the longer (18 km) SPR 

traverse included substantial portions of the UPR (12 km) traverse, again to allow meaningful 

comparisons, yet it ranged further and added an additional sampling station (see Figure 3). Two 

additional traverses supported the long-duration SPR tests which lasted 3 full days and 2 nights: 

day one coincided with the above SPR traverse, yet days 2 and 3 covered new territory and 

mandated dedicated traverses (see Figure 4) for a cumulative range of 56 km for the continuous 

3-day test. A detailed traverse package, detailing way points, sampling stations, science 

objectives and timelines served as the basis for extensive pre- EVA science briefings of both 

crews. 

SCIENCE OPERATIONS: 

 The science operations were substantially patterned after similar Apollo training exercises 

and focused on two basic functions: a) field observers and b) science back room. 

 Typically two field observers, one for each crew, followed the suited subjects in the field and 

made notes about the quality of observations, sample selections, and sampling procedures. These 

field observers were equipped with radios and thus able to listen to the crews’ descriptions 

throughout the entire traverse, including the comments offered while driving. 

 The science back room consisted of a Field Geology PI and one or two CoIs, a Science 

Capcom, a Navigator, and a Note Taker. The table below identifies the individuals and their 

specific functions during diverse traverses; the objective of these rotating assignments was 

obviously to cross-train a number of individuals for future field tests of this nature. The back 

room was in continuous radio contact with the crew and able to advise the latter, if needed. 

Also, up to 5 video cameras were displayed in the back room: forward, aft facing and central 

mast-mounted devices on the rover (including panoramic capabilities), and especially two suitmounted cameras, one each for a suited subject, that also could acquire single frame still images. 

These real time video capabilities imply vastly different back room operations and requirements 

relative to Apollo (which almost exclusively relied on verbal descriptions only). Typically, after 

completion of each traverse a science-debriefing re. operational science issues was staged during 

which field observers and back room personnel offered constructive critique. An overall science 

briefing was held on the last day of field camp (11/30). The science team concluded that suitable 

observations and samples were acquired to address all major pre-mission science objectives. 

 EV 1 EV 2 FIELD, A FIELD, B CAPCOM PI CoI, A Navigator Notes 

 

UPR, A Gernhardt Garry Lofgren Chapmann Horz Kring Eppler Wilkinson Nelson 

UPR, B Walheim Lee Chapman Kring Eppler Horz Lofgren Wilkinson Nelson 

SPR, B Walheim Lee Eppler Horz Kring Lofgren Chapmann 
98 

SPR, A Gernhardt Garry Horz Kring Lofgren Chapmann Rice / Lee Wilkinson Nelson 

Day2, A " " Lofgren Rice Chapmann Kring Horz Wilkinson Nelson 

Day3, A " " Chapmann Horz Lofgren Rice Kring Wilkinson Nelson 

 

SPR SCIENCE TEST: 

Although not part of the initial test plans, most science team members were afforded the 

opportunity to ride in the SPR and to compare the observations from inside the SPR with those 

of a shirtsleeved geologist walking across a specific test site. The latter was some 200 x 200 m in 

extent and contained tell-tale sedimentary structures as well as a wide diversity of basalts, the 

latter in the form of dislodged float covering the local slope. During both activities, each lasting 

20 minutes, the geologists verbalized their observations and recorded them via dictaphone, 

walking first, followed by observations inside SPR. 

 A general description of the test area is attached to this report; detailed analysis of this 

test is in progress, yet all participants deemed this test significant and highly beneficial. A 

dedicated report is anticipated. 

SAMPLE STATISTICS: 

All rock and soil samples collected during the 6 EVAs were placed into prelabeled bags 

and shipped to JSC for additional analysis that will be documented via a separate report. The 

following, first order results were obtained to date: 

Note: a) variance among crews with crew B tending to collect more samples and/or A 

being more selective. Also, crew B tended to collect modestly larger samples. 

 b) EVA time is total hours; n/hr and kg/hr should be recalculated for “boots on the 

ground” time (which was not readily available at the time of this tabulation). 

 c) Sample mass collected during approx. 50 hours of total EVA approaches the 

current limit for sample return mass (100 kg) for a base-line Earth return for 

Constellation (the field mass is pure sample and does not include additional 

containers and packing material, nor any biological specimen). 

 Sample Bags Total mass average EVA n/hr kg/hr 

 sample mass (hours) 

 n kg g 

UPR, A 26 12.410 477 6:30 4.0 1.91 

UPR, B 33 18.147 550 6:30 5.1 2.79 

SPR, B 52 20.787 400 9:30 5.4 2.19 

SPR, A 37 18.056 488 9:30 3.9 1.90 

SPR, Day 2 39 14.653 376 9:30 4.1 1.54 

SPR, Day 3 19 7.128 375 7:00 2.7 1.02 

 Totals 206 91.181 442 48.5 4.3 1.88 
99 

Figure D1: The Black Point Lava Flow and its surroundings; the circle is 10 km in diameter and centered on 

the location of base camp, at the western edge of this 2.4 MY basalt flow. 
100 

Figure D2: Detailed view of Black Point Lava Flow and photogeologic map produced by the Science Team; 

the actual basalt flow is not explicitly mapped in this rendition, but other volcanic features are (in red), 

suggestive of additional volcanic events. The detailed mapping concentrated on more subdued morphologies, 

suggesting different rock types. The traverses concentrated on the Western edge of the flow and the adjacent 

units (brown ) to the West, as well as on the additional (red) volcanic formations. 
2

4

UPR Traverse

6:30 hrs

Figure D3: 1 Day UPR and SPR trav

the SPR traverse was laid out along th

the red line suggests the fastest way b

followed the yellow line with the excep

constituted Day 1 of the long duration

(rather than towards base camp) from

101 

1b 1a

3

4

averses; note the addition of Station 3 for SPR over that

g the green line, which however was not doable because o

 back to base camp, in case of unforeseen delays. The ac

ception of Station 2, where the green line was followed. T

ion (3days/2 nights/56 km total travel) tests, yet SPR bac

om Station 5 for an overnight stop close to the blue spot

at of UPR. Initially, 

e of too many fences; 

 actual traverse 

. This traverse 

back tracked S 

ot (see Fig. 4).
102 

2

5

1

3

SPR 3 Day Traverse

Day 2

N2

N1

2

3

1

4

5

SPR 3 Day Traverse

Day 3

N2

Figure D4: Traverses of Day 2 and Day 3 for the long duration (3 days/2 nights/covering 56 km) SPR tests; 

overnight camps are depicted in pink as night 1 (N1) and night 2 (N2). 
103 

INDIVIDUAL REPORTS:

MARY CHAPMAN 

UPR/SPR Field Tests 

Field Observer Comments for UPR, B: 

Distances were hard for the subjects to judge, but overall the exercises went well. Bagging the 

samples seemed hard for all the crews each day including this one. The suit subjects were unable 

to walk the contact of the BPLF to find the pepperite at the base (10 feet away)—because of end 

of the day fatigue. 

Field Observer Comments for UPR, A: 

There were numerous problems with sound systems on this day (people talking over each other 

etc.). 

Col, A Comments for SPR, B: This task was basically to make sure labels on sample bags were 

written down as they were received over the comm. system, keep track of timing between 

Engineering Capcom and training team, and observe the PI & CapCom. Not too much change in 

performance of the crew from the previous day. 

PI, Comments for SPR, A day 1: This task was to keep track of cameras, take images as needed, 

and make science requests for CapCom to pass onto team. I thought the team did very well and 

even located a contact of BPLF with little coaching. There were lots of technical difficulties 

with cameras and sound systems on this day. Most of the day we were without suit cameras. 

Crew A took a different route and split up a bit to cover territory. 

CapCom Comments for SPR, day 2: This task was to pass on requests from PI and Science team 

to training crew. I think the day went well, even when the crew got out of comm. range they 

were still able to function very well. This was one long day though, with some vehicle problems 

at the end of the day. The crew made some very good observations and interpretations on the top 

of the flow on this day. 

Field Observer Comments for SPR, day 3: Short day, the crew performed very well. However 

the backroom left them very little rope for making their own decision, requesting pinpoint 

stratigraphic data on flows to the extent that the crew was overlooking very important 

inclusions/fabric of lava flow surface. I believe the crew would have performed better with less 

backroom requests. 

SPR Science Test: I was very impressed with the SPR performance, the view from the bubble 

when SPR was lowered was excellent and the saving for human excursion was impressive. 

However, some cliff surfaces were out of reach because of large boulders obstructing the way of 

the SPR and the ergonomic space to get in and out of the floor bubble was awkward and tight. 
104 

My final comment is that it would be great if the Science Team had the ability to pinpoint objects 

and locales on the computer screen images of SPR & suits for transmission to the training crew, 

so the crew could route themselves onto requested targets. 
105 

DEAN EPPLER

TRIP REPORT: 

This was a very impressive test, easily the best test since Joe Kosmo first took hardware to the 

desert in 1998. The things that stand out the most were having a limited, well-defined set of test 

objectives, participation by individuals and hardware limited to those groups and machines that 

would support those objectives, and very hard work by all the support people to be able to pull 

off the test. In the latter category, everyone stood out: Joe Kosmo and Barbara Romig for 

organizing and directing the effort, all of Rob Ambrose's people for support all the Chariot and 

SPR activities, Fred Horz and his entire science team, the SPR team under Mike Gernhardt and 

Andrew Abercromby, the communications folks under Mark Seibert that got the comms 

working, and Zane Ney and his folks for doing valiant data gathering on the operations in realtime. 

Some specific comments as follows: 

Suits – the suit mockups purchased from Global Effects probably worked as well as they could 

under the circumstances, but they were clearly not designed for such hard work under difficult 

environmental conditions. Having said that, they provided a good data set on the differences 

between using an unpressurized rover and the SPR, something that I was skeptical could be done 

from a limited run in one of the suits. The suit techs are to be commended for their heroic efforts 

to keep suits up and running. One issue I did note is that the accommodations in the suit 

necessary to test the ability to self-don in the SPR put a significant strain on the suit subjects, 

considerably more (in my opinion) that a real pressure garment would have. I think this was 

necessary for this test, but having proved the point, I think we should devote some time to 

figuring out a method of allowing a shirtsleeved subject to interface with the suit port hardware 

(for example, something similar to a conventional packframe with the appropriate interfaces that 

allows crewmembers to operate out of the SPR) without putting the unnecessary strain on the 

subjects. Something like this was developed to use in the Apollo geology joint-integratedsimulations (see attached photos) so the crew could practice with volumetrically and 

procedurally accurate hardware without the physical strain of a full A7LB and PLSS. I think 

some effort should be put into developing this kind of concept before the next field test, as I'm 

certain the SPR will be with us for some time. 

SPR – Great vehicle, great concept. The SPR team is to be congratulated on putting together 

such a complete, functional mockup in such a short time. Its ability to do reconnaissance 

operations is unmatched – I think this is one of the best new approaches that has come out of the 

LAT process. The one issue I have with the vehicle is that while it provides a great platform for 

reconnaissance activities, the complicated geology of the Moon will still require boots on the 

ground work. The best illustration of this is that during the week I was on site, no rover crew 

accurately identified the location and altitude of the contact between the Blackpoint Lava Flow 

and the underlying member of the Moenkopi Formation. Identifying contacts is a critical activity 

in geology, and one that we will need to be able to do on the lunar surface. The disposition of 

considerable Blackpoint boulders on the slopes made finding this contact difficult, but it was 
106 

possible to find it by doing what Dave Kring described as "looking for rattlesnake kisses.” 

Finding this contact required a close-up inspection of the slopes that the SPR was not able to 

provide, and could only be done by getting out of the vehicle and walking the slopes until that 

contact could be established. This is something we will need to work into future field operations. 

Having said that, the SPR worked superbly, and it clearly will allow the crewmembers to do the 

initial reconnaissance in low-stress comfort so that, when they do egress and do the detailed 

geology, they will be more apt to make good observations. 

Chariot – Again, great vehicle, great concept. Several things were very impressive to me: first, 

the ability of the vehicle to go into country that only the HumVee could adequately follow in; 

second, the robustness of the vehicle in spite of the punishment it took, and third, it's ability to be 

fixed without complicated procedures and tool sets, and to operate in degraded modes that still 

allowed the mission to be completed. 

Science Operations – The science operations setup that Fred Horz and Gary Lofgren came up 

with worked very well, in my opinion, far better than we have been able to do in the past. I think 

it worked well because it had limited staff, and the positions rotated so each team member 

worked the back room and got into the field with the crewmembers. Some science operations 

practices that the crewmembers devised that "bleed over" into general operations need to be 

noted: first, parking the SPR facing the worksite the suited crewmember(s) will be working so 

that they can be observing and coming up with detailed plans was a great practice; second, 

conducting solo EVAs with one crewmember out, one in worked very well and should be part of 

the standard operations on the lunar surface; third, the use of a high resolution suit-cam that the 

backroom can do frame-grabs from proved to be extremely useful, both for backroom situational 

awareness, and for removing some of the documentation workload off the crewmembers. 

Anyone that has any specific questions, please feel free to contact me. 

Dean Eppler 

SAIC-Constellation Lunar Surface Systems Office/Planetary EMU Crash Test Dummy (otp) 

281-244-8216/dean.b.eppler@nasa.gov 

Note from Eppler, dated 11/5, to Science Team: 

The one point I'd like to make, relative to the science activities, is that one of the most important 

things one has to do in the field geologically is establish the geographic location of contacts. 

For the two SPR and two UPR runs, nobody ever established that contact, and at least one 

subject had a completely wrong impression of where it was. I was able to get close to it on a 

couple of occasions doing what Dave so aptly called, "kissing rattlesnakes", and it was not near 

where one would guess, based on the view from either SPR or UPR. I think we need to call out 

that particular point in our evaluation, to emphasize that the only way to find many kinds of 

geologic data is by getting out and poking around at a detail you cannot do by remaining in a 

rover. 
107 

FRIEDRICH HORZ

Science Related Impressions 

Positive: 

• The SPR/UPR is an amazingly nimble vehicle with outstanding terrain capabilities and 

excellent range and speed, far better than the Apollo rover. 

• The SPR cabin allows for essentially unobstructed (> 1800) views of the surrounding 

geology, including surface details (through the curved front window, a feature that must 

be preserved, yet I am not sure whether the “bubble” is really needed). The elevated 

viewing position in the cabin is highly suited for “float-mapping,” the dominant mode of 

operation on the Moon because of crater ejecta. 

• The SPR allows for longer ranges/more mobility than UPR, yet total “boots on the 

ground” time is only modestly longer; crew reports that shirtsleeved driving is a welcome 

reprieve from wearing the cumbersome suits during long station times. 

 Thus SPR and suit port concept seem highly beneficial for science ops. 

• One man EVAs on short stops seem promising, as is independent rock sampling by 

individual crews; these 1 man science-activities seem desirable, yet they need extensive 

practicing and associated procedures. 

• Suited geologists in the field added considerable realism to these tests 

• The SPR video cameras (mast; aft; bubble) are excellent and highly informative 

• The suit mounted video cameras with still capability are very useful and a “must.” 

• Audio communications were excellent; the video stream suffered on occasion from 

camera-related failures. 

• GPS navigation was excellent, accurate, and of great help to back room. 

• The interaction of the “science” capcom with the “mission control” capcom was excellent 

and should be implemented during real lunar missions. 

• “Can Do” team spirit was omnipresent and Apollo-like. 

• Overall: this was a highly focused campaign; general operations proceeded nominally 

along well-perceived plans; most test objectives were accomplished, some exceeded. By 

comparison, Moses Lake was somewhat disjointed as too many tests/operations of 

diverse systems took place simultaneously. 

Negative: 

• Suit mounted video cameras failed too often; must be redesigned/ruggedized (note: kudos 

to the KSC folks involved in developing this capability with off the shelf hardware and 

software that were not intended for demanding field work). 

• EVA tools and tool pallet were of low fidelity and must be improved; this includes 

provisions to attach diverse tools to the suit while EVA, especially for single man 

operations. 
108 

• The utility of the extensive/cumbersome Apollo-photodocumentation –including the 

gnomon device- must be reevaluated in view of the video capabilities which seem 

adequate to document the sampling process. 

• Traverse planning could have been better re. trafficability, fence crossings etc; an 

advance team should have visited the site to lay out the final routes; some of this had to 

be done in real time and associated modification of existing traverses distracted from 

other activities.

• Science back room seemed understaffed (3 folks for 5 cameras etc), yet placing the 

science back room into the field (rather than Houston) was very beneficial. 

SUGGESTIONS/LESSONS LEARNED: 

 Minor: 

• Redesign surface tools and their mounting on tool pallet and suit 

 Larger rover-mounted bag to deposit all collected samples 

 Less friction in tongs; make second tong for independent EV1 and EV2 ops 

 Better mount for individual sample bags on suit 

 Better mount for sample collection bag (black nylon bag) on suit 

 Possible mounts/tethers for tongs and hammer on suit 

 Fixed mount of still cameras (if used) on suit 

 Ruggedize video suit cameras 

 Practice, practice, practice the use of tools and associated procedures 

 A number of committees are looking into these general issues and need our 

 collective input, notably CAPTEM. 

* I was somewhat reluctant to buy into the quantitative evaluation of “science 

 productivity” as it is an intrinsically difficult task, possibly flawed by subjective 

 judgments; however, there was an unusual degree of internal consistency (identical 

traverses; identical personnel; well understood criteria etc) during these tests and I think 

the numerical rankings will be meaningful. 

 

Major: 

• Develop operational concepts and requirements for Science Back Room 

 The advent of real time, digital imagery will make for dramatically different back 

 room operations compared to Apollo; details need to be worked out. 

• Hybridize UPR/SPR by advancing the “cheap seat”- concept to include the ability 

 to drive the SPR externally, while suited. 

• Provide for some mechanism external to SPR, most likely at the front that can grab rocks 

and soil samples while the crew is inside and shirtsleeved. 

• Instrument assisted “high-grading” of rocks, such as via handheld XRF, IR or Raman 

devices, may be difficult to accomplish in real EVA time, as these analyses typically 

take minutes to complete, a rather long time compared to crew activities and 

observations (the crew is quickly on to another rock or topic; the back room was 

frustrated that it took a long 5 sec to capture and display a still-image). Point is: 
109 

instrument assisted highgrading seems most profitably done during sleep times etc. 

Efficient use of SPR suggests that considerable thought go into the 

design/development of rover-mounted analysis capabilities, such as close up photostation, XRF or IR/Raman etc. Rocks that turn out to be duplicates/ uninteresting can 

be tossed by the crew, once EVA. I do not think that instruments taking longer than a 

minute to produce analyses should be carried by the crew. 
110 

DAVID KRING 

Evaluation of Science Operations 

Top-level Evaluation 

• The science team was an excellent mix of Apollo-era geologists, mid-career lunar geologists, 

and students. The group provided experience with procedures that work, lunar-relevant 

geology, test-site geology, and exposure to new technical capabilities. 

• The entire simulation team was excellent. The program managers identified people with the 

technical capability and can-do attitude needed to move the program forward in a substantive 

way. 

• Collectively, the simulation integrated a broad range of expertise (for example, astronaut 

office, suit specialists, rover specialists, mission operation specialists, communication 

specialists, crew trainers, and geologists) to produce a realistic simulation and, thus, much 

better results than available previously. The outcome of the simulations verifies several of 

the conclusions in a previous report1

. 

• It became clear that realistic lunar surface operations involving lunar-like geology affect 

traverse activities and, thus, need to be part of future simulations so that accurate accounting 

of traverse timelines, consumables, and crew exertion in different suit-rover combinations 

can be made. 

Black Point Simulations vs. the Moses Lake Simulation2, 3 

• The flight rules were much clearer in the Black Point simulations, greatly enhancing the 

flow of activity throughout the simulations. 

• Having the science backroom in an on-site field trailer is much more productive than at a 

distant location. It provided the backroom isolation needed during a simulation, while 

facilitating communication with all other team members to upgrade operations during an 

extended (2-week) series of tests. 

• Good traverse timelines are essential. This was a lesson-learned from the Moses Lake 

test of June 2008. The Black Point simulations demonstrated that a detailed traverse 

timeline provides a more realistic test, including serious trades between objectives when 

issues (like hardware problems or an unexpected science discovery) occur during a 

planned traverse. 

• A geologist on the crew greatly assisted in station activities and the crew’s ability to 

implement changes in planned activities that the local geology may dictate. 

1

 Developing a Concept for Astronaut Training and Analogue Studies for Lunar and EVA Surface Operations. 

Report from David A. Kring to Wendell Mendell, Constellation Systems Program Office, 22 September 2007, 5p. 

2 Science Operations during the Moses Lake Field Test, 9-12 June 2008: Perspective from the Science Backroom, 

JSC Bldg 9. Report from David A. Kring, 1 July 2008, 4p. 

3 Geologic View of the Moses Lake Test Site Based on K-10 Red Rover and Crew EVA Observations: Preliminary 

Report. David A. Kring, 1 July 2008, 5p. 
111 

UPR vs. SPR 

• SPR is easier on crew; the crew had more energy at stations when traveling in SPR and, 

thus, was more productive at each station. 

SPR vs. Geologist in Shirtsleeve 

• The view from the SPR is very good. I saw most of the features seen in shirtsleeve at the 

scale of outcrops and individual rocks, although I was unable to rotate the latter in the 

light to better evaluate crystal morphologies. 

• The SPR was nearly as good as shirtsleeve in the limited test site, but the result will be 

highly dependent on the complexity of the topography and geology. For example, I 

stepped over small vertical outcrops that were impassable for the SPR. 

• The biggest difference between the two methods is reaction time. If I needed to turn to 

modify my view or walk in a different direction, I can implement that change 

immediately in shirtsleeve. In the SPR, there is a built-in delay needed to communicate 

an action to the commander and for him to make the mechanical adjustments needed to 

change the SPR’s motion. 

Operational Lessons Learned from the Black Point Simulations 

• Rover imaging is critical to the success of the science backroom and its capability to 

advise crew with traverse activities. It provided the backroom, for example, the 

capability to examine the geologic context of a station and, thus, direct crew when they 

were inhibited by the “tunnel vision” that can occur within helmeted suits. 

• If the SPR is oriented correctly at each station, EVA crew (and science backroom via 

video) can evaluate the station during the suit egress sequence. 

• Suit video is also critical: it provided immediate documentation of sample context and 

the samples selected. 

• A navigational GPS tracking tool should be available to the science backroom to 

maximize the value of its interaction with crew and adjust traverse activities if needed. A 

window with current crew position data on one of the two Science PI monitors will also 

help future simulations. 

• Better science could have been accomplished by the crew if they were trained for that 

particular type of geologic site. In this case, a 3-hr training field trip to the nearby SP 

crater and lava flow would have enhanced crew capability during the UPR/SPR tests. 

• Rotation of science team members through the positions of Science Capcom, Science PI, 

Science Co-I, and Field Geologist was very good. Not only did it provide an opportunity 

for cross-training and different perspectives, it also kept the team fresh over the course of 

a 2-week test with extensive overtime hours. 

• Situational awareness and capability to multi-task are critical skills for the Science PI and 

Science Capcom. 
112 

• A new traverse option was identified: EV1 can scout a second station in SPR, while EV2 

is conducting sampling and other EVA activities at the first station. 

• Potential new rover tools: (i) A telescopic imaging system might assist crew on a rover 

and (ii) a robotic sample manipulator or rake with controls within SPR might assist crew 

when EVA is not an option. 
113 

GARY LOFGREN

Overall impression: This was an engineering performance test of two rover concepts, 

unpressurized (UPR) and small pressurized (SPR). The rover and a support crew of 10’s of 

people provided the core of the exercise and they performed well keeping the rover working over 

very difficult terrain for the entire exercise. This was an engineering activity supported by 

mission operations people and evaluated by human factors people. The goal was to contrast the 

different modes of operation between the two rovers concepts and their relative merit. That goal 

appears to have been achieved. 

Rover Operation and design: The rover is a complex machine designed to replace the Apollo 

Lunar Rover and it does that very well; I was very impressed with its capabilities. The rover in 

either of its configurations was able to traverse without difficulty very rough terrain littered with 

large, angular basalt boulders and steep slopes that stopped all but a Hummer. I found both the 

UPR and SPR to be functional and well thought out concepts. The standing position on the UPR 

was a surprise, but once explained and observed in operation was found to be a logical design. 

The supports that hold crew in place relieves them of much of the weight of their suit while they 

move. The only disadvantage I could see was the increased distance between the eyes of the 

crew and the ground. A forward looking camera with a display for the crew positioned like the 

bubble camera on the SPR (see below) would help the crew with a close-up view of the surface 

and the rocks thereon. The SPR design and concept has definite advantages. The crew has more 

EVA time for doing geology and drives between stations are done in shirtsleeve comfort. The 

EVA can be planned from the inside in conjunction with science support from an outpost or an 

Earth bound science support team. Clearly the 8 hours of EVA time can be used more 

effectively so that more time is spent doing science. I did an observation exercise from within 

the SPR and the visibility is superior as currently designed (hopefully that level of visibility can 

be maintained in the lunar version). The SPR had 5 video cameras, one on a mast that stands 

above the rover and has a 360 rotation; it is perfect to follow the activities of the crew. There is a 

camera in the bubble low and in front that points straight ahead and gives a good constant view 

forward and can be turned down to image a rock. There is a rear camera that functions mainly as 

an operations camera to watch the crew enter their suits, but gives a rear view when needed. The 

mast camera can also give a rear view. 

Astronaut performance: For this exercise a trained geologist was teamed with an astronaut for 

the two person crew. Considering the lack of science training possible before the exercise, this 

provided a crew that could deal with the science in a meaningful way. Minimal training was 

given in the use of the geologic tools, which mimicked the Apollo tools, and sample collection 

techniques and documentation. It was noticeable how quickly the astronauts picked up the 

science from the geologists. The natural observation talent of the astronauts was also evident. 

Developing the common vocabulary, as was one important training activity during Apollo, was 

the obvious limitation. The enthusiasm for the activity was obvious. I think most people 

become so when learning more about the ground under their feet. 

Science operations: My contribution was to help provide the Science reality of the exercise. 

The Chariot team wanted scientifically realistic traverses with science objectives of varying 
114 

value and traverse stations of relative importance. They wanted to be able to grade the quality of 

crew performance in the UPR vs the SPR and needed basis for that evaluation. 

 Science objectives and Traverse planning: The first step was to find a location that 

provided challenging terrain and interesting and reasonably complex geology. The Flagstaff 

location near the Black Point lava flow is such a site. There are several geologic objectives of 

varying importance (dependent most on the point of view of the planners) that allows the 

definition of objectives of different value so that stations and station activity can be prioritized 

and their successful completion graded. We developed Apollo style traverses based on photogeologic information and a produced a traverse map on such a photo base. A broad designation 

of overall science objectives for the area led to detailed traverse planning. Stations were chosen 

to provide the information necessary to answer the questions that met mission objectives. Nearly 

identical traverses were created to compare the effectiveness of the two different crews and to 

compare the UPR with the SPR. The crews were given overall site briefings and detailed station 

by station briefings on each traverse. 

 Science operation: Science operations attempted to simulate all aspects of science support 

for a mission. Four scientists participated throughout the 2 weeks, Horz, Kring, Chapman, and 

me. Eppler was there the first week and Rice and Lee (the latter after completing suited geologist 

activity), the second. Two scientists moved with the crews in the field and the remaining 

scientists provided the science backroom (SBR). Roles were rotated so that all scientists were 

both in the science support room and in the field. In the back room the responsibilities were 

rotated between being the science PI, support to the science PI, and the science capcom. 

Evaluations of the crew performance were completed from the point of view of the field observer 

and the SBR. Based on my Apollo experience, this was a very realistic science activity. 

Having a science capcom that worked with a mission operations capcom was not 

something done on Apollo, but worked well in this exercise. Such close communication with the 

crew would be nice to have in the real case, if possible. Apparently this is done for station and 

for this exercise that was the model. The video cameras available on the SPR and the astronauts 

provided a marked improvement over Apollo video and clearly need to be the goal for this 

second exploration of the Moon. The suit cams allow the scientists to see what the astronauts 

were seeing. The cameras had the provision for the SBR to capture stills at their discretion and 

proved to be useful for documentation of samples collected and their setting. Collected samples 

could be held up to the camera for a close up. A mast video camera on the SPR allowed the SBR 

to follow the crew much as the TV camera on Apollo, but with much improved image quality 

and control. 

Lessons learned: It is clear that the methods of sample documentation and general 

observations of the crew will be entirely different this time and deserve careful thought. For 

example, each camera on the Moon will require a single SBR person to accumulate the images 

and evaluate their content. The images will be an incredibly important resource and will need to 

be indexed for quick retrieval. The possible access to near real time imagery will allow much 

more meaningful interchange between the crew and the SBR both in real time and for near future 

traverse activity. This interchange could lead to effective high-grading during collection or at 

subsequent stations on a single traverse. The dominant rock types could quickly be established 

and then immediate recognition would be possible by the crew with some briefings from the 

ground. An XRF tool would serve us well to supplement the high-grading efforts. One point 

became clear, the gnomon needs to go and we need to find a way to capture the information 
115 

provided by the gnomon that is necessary in other ways. Jack Schmitt has commented often 

about how onerous the documentation procedures were. Many things done for Apollo, however, 

will not change. The basic training should be the same, that is, to create the common science 

vocabulary and comfort with routine activities. 
 
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 November 2010 NASA Technical Paper 

4. TITLE AND SUBTITLE 5. FUNDING NUMBERS

Desert Research and Technology Studies (DRATS) 2008:

Evaluation of Small Pressurized Rover and Unpressurized Rover Prototype Vehicles in 

a Lunar Analog Environment

 

6. AUTHOR(S) 

Andrew F. J. Abercromby, Ph.D.,Wyle Integrated Science and Engineering Group; 

Michael L. Gernhardt, Ph.D., Johnson Space Center, Houston, Texas; 

Harry Litaker, Lockheed Martin 

 

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REPORT NUMBERS

Lyndon B. Johnson Space Center 

Houston, Texas 77058 

S-1082 

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National Aeronautics and Space Administration 

Washington, DC 20546-0001 

TM-2010-216136 

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13. ABSTRACT (Maximum 200 words)

A system of two or more Small Pressurized Rovers (SPRs), also referred to as Lunar Electric Rovers (LERs), is an integral part of 

NASA’s plans for returning humans to the moon. In the SPR concept, each vehicle includes a small pressurized cabin to safely 

sustain two crewmembers on the surface for 14 to 28 days. Through suit ports, crewmembers may rapidly egress and ingress the 

cabin for EVAs. In addition to achieving a surface exploration range that is potentially orders of magnitude greater than what was 

achievable during the Apollo Program, the SPR concept offers many other benefits, particularly with respect to the health, safety, and 

productivity of crewmembers. 

The primary purpose of the DRATS 2008 field test, at Black Point Lava Flow in Arizona, was to objectively and quantitatively 

compare the scientific productivity and human factors during 1-day exploration, mapping, and geological traverses performed using 

SPR and Unpressurized Rover (UPR) prototype vehicles. The habitability, human factors, and performance characteristics of the SPR 

vehicle and crew were also recorded throughout a high-fidelity 3-day lunar traverse simulation. 

Quantitative assessment of crew productivity by on-site expert field geologists found that compared with UPR traverses, the same 

crewmembers were 57% more productive during SPR traverses and used 61% less EVA time. The habitability and human factors of 

the SPR throughout the 3-day traverses was acceptable, although suggested modifications to several vehicle subsystems were 

identified in the assessment. 

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DRATS, SPR, LER, rover, lunar, traverse, Black Point Lava Flow, 131 

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