June 2011 

NASA/TM–2011-217159 

Exploration Planetary Surface Structural 

Systems: Design Requirements and Compliance 

John T. Dorsey 

Langley Research Center, Hampton, Virginia 
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June 2011 

NASA/TM–2011-217159 

Exploration Planetary Surface Structural 

Systems: Design Requirements and Compliance 

John T. Dorsey 

Langley Research Center, Hampton, Virginia 
Available from: 

NASA Center for AeroSpace Information 

7115 Standard Drive 

Hanover, MD 21076-1320 

443-757-5802 
1/13

Exploration Planetary Surface Structural Systems:

Design Requirements and Compliance

Abstract

The Lunar Surface Systems Project developed system concepts that would be necessary to 

establish and maintain a permanent human presence on the Lunar surface. A variety of specific 

system implementations were generated as a part of the scenarios, some level of system 

definition was completed, and masses estimated for each system. Because the architecture 

studies generally spawned a large number of system concepts and the studies were executed in a 

short amount of time, the resulting system definitions had very low design fidelity. This paper 

describes the development sequence required to field a particular structural system: 1) Define 

Requirements, 2) Develop the Design and 3) Demonstrate Compliance of the Design to all 

Requirements. This paper also outlines and describes in detail the information and data that are 

required to establish structural design requirements and outlines the information that would 

comprise a planetary surface system Structures Requirements document; provides a status of the 

data sets needed to establish requirements (most are currently incomplete or missing); and 

proposes an approach for developing the necessary data and information. The resulting plan is 

intended to serve as the framework for implementing a planetary surface structural systems 

technology development process to support exploration efforts.

Introduction and Objectives

The Lunar Surface Systems (LSS) Project, within the NASA Constellation Program, was 

responsible for defining and developing system concepts that would be necessary to establish 

and maintain a permanent human presence on the Lunar surface. Examples of potential system 

concepts include Habitats, Surface Mobility Devices, Robotic Manipulators, and Surface Power 

Generation and Storage. The lunar architecture studies investigated a wide variety of 

implementation scenarios that met overall Vision for Space Exploration (VSE) objectives, with 

different scenarios emphasizing meeting those objectives in different sequences. A variety of 

specific system implementations were generated as a part of the scenarios, some level of system 

definition was completed, and masses estimated for each system. Because the architecture 

studies generally spawned a large number of system concepts and the studies were executed in a 

short amount of time, the resulting system definitions had very low design fidelity. Many 

different mass estimation techniques were used to generate subsystem (such as structures, power, 

environmental and life support, avionics, etc.) definitions and masses. Reference 1 gives an 

overview of the methods used to define and estimate the mass of habitation structures, as well as 

a summary of the limitations of those methods. In Reference 1, an important demarcation is 

made between the structural concept definition that was being performed in LSS to support the 

architecture studies, and structural design. This distinction is critical because only a very limited 

amount of information can be inferred from concept definitions. In particular, technology 

development requirements cannot be inferred from concept definitions because those 

requirements are particular to and change with a given system implementation, and that 

implementation depends on, at a minimum, a conceptual design.
2/13

The development steps that are required to field a particular structural system can be categorized 

(at a broad level) into: 1) Define Requirements, 2) Develop the Design and 3) Demonstrate 

Compliance of the Design to all requirements. Currently, a comprehensive set of Structural 

Design Requirements (SDRs) does not exist for systems that must survive and operate on the 

lunar and other planetary surfaces (including smaller bodies such as Near Earth Objects). As a 

result, it is very difficult to perform even a conceptual structural design with any degree of 

confidence since compliance to major (undefined at this point) requirements may be lacking in 

the system. However, in order to meet any future exploration program mission goals, it is clear 

that the design process for planetary surface systems needs to begin immediately if the required 

systems are to be delivered in a timely manner to meet exploration flight manifests. The 

objectives of this paper are to; 1) outline and describe in detail the information and data that are 

required to establish structural design requirements, 2) outline the information that would 

comprise a planetary surface system Structures Requirements document, 3) provide examples 

and a status of the data sets needed to establish requirements (most are currently incomplete or 

missing) and, 4) propose an approach for developing the necessary data and information.

Design Requirements and Supporting Information

The full suite of Exploration Planetary Surface Systems will incorporate a wide variety of 

structural and material concepts and systems. Some of the structures will be pressurized (habitat 

for example) while many others will be unpressurized (rover chassis, solar arrays, etc.). Some of 

the structures will house people, transport people, or interact with people, while others will 

transport and handle critical flight hardware. The requirements developed to design the structural 

systems must be comprehensive and account for the unique environments (on a particular 

planetary surface, as well as transportation to the surface) that the systems will be exposed to. 

Decisions will have to be made as to the applicability and potential to incorporate Earth-based 

requirements as they might apply to the planetary outpost (OSHA safety for example) as well as 

transporting and handling flight critical and human payloads (NASA Critical Lift requirements, 

reference 2).

Overview

The purpose of having a set of SDRs is to ensure a minimum level of safety in any structural 

system developed under the auspices of a particular regulating authority. Thus, the requirements 

represent a general set of standards that are independent of any particular material/structural 

system design and implementation, and every system that is to be operated must show that it 

complies with all of the applicable requirements. In general, an evaluation of the structural 

system under typical load and environmental spectra must show how catastrophic failure due to 

any degrading environments (temperature, radiation, vacuum, for example), material specific 

response to loads (creep, fatigue, fracture, for example) or accidental damage can be avoided 

throughout the operational life of the structural system. Generally, this can only be assured when 

there is an adequate inspection program, so the evaluation must also result in an inspection and 
3/13

maintenance procedure. The evaluation must be applied to each Principle Structural Element 

(PSE) in the system whose failure, if it remained undetected, would lead to loss of the system.

In general, two different structural design categories (damage tolerance and safe life) exist and 

the evaluation must show compliance to whichever philosophy is chosen for the system. In the 

first category, damage tolerant structure, multiple paths exist for redistributing loads around a 

damage site. The evaluation must show that any damage (initiated by fatigue or accident for 

example) will never propagate to failure prior to detection. The evaluation may use a 

combination of test and analyses. Damage propagation must take into account the expected 

spectrum of loading (and resulting stress) and environmental exposure expected in service. 

Inspection frequencies must be determined based on damage propagation life from a detectable 

size to a critical size at limit load. The ability to repair damage is inherent in the damage 

tolerance approach and repair techniques must be developed and validated to be compatible with 

the planetary surface environment. For planetary surface structures, detectable damage will have 

to be repaired in the field for the structure to remain in service. The second category, safe life, 

applies to single load path structure where it can be shown that damage tolerance is 

impracticable (from inspection, not economic considerations, with landing gear and engine 

mounts being two examples for commercial transports). Safe life structure is defined as that in 

which any initial flaws can propagate and become critical before they are detectable in service. 

Substantiation is required by test, and based on those tests, a “safe life” is established for the 

structural element and the element must be replaced at the end of its life.

The broad categories of information and data that are required to perform structural design 

consist of the following; natural environments, threat environment, design loads, material 

properties, structural design requirements and design compliance. In general, all of the categories 

except Design Requirements and Design Compliance are independent of a particular 

structural/material design implementation. Within the realm of Design Requirements, many will 

also be independent of material/structural implementation and apply to all structural systems. 

The degree and depth to which data and information exist for each category will determine 

whether or not, and to what level of fidelity, structural design can be performed. In general, there 

is a minimum amount of information and data that will be required to cross the demarcation line 

from conceptual definition to conceptual design. In the following sections, each information 

category will be described along with examples of data required to perform such a design.

Natural Environments

The natural environments are the complete set of environments that the structural system will be 

exposed to during its entire life cycle. This includes exposure to Earth environments during the 

periods of storage before flight, transportation to the launch site, storage at the launch site, 

integration with lander and launch vehicle and waiting for launch on the pad. It also includes 

exposure to the in-space environment in low Earth orbit, planetary transit and planetary orbit; 

and exposure to the plantary surface environment. Examples of environments to consider for 

each phase are listed in Table 1.
4/13

Table 1. Natural Environment Examples by Mission Phase.

Mission Phase Environment Definition Required

Earth storage, transportation, launch pad, 

launch

- Temperature (maximum and minimum)

- Temperature cycle, time at temperature

- Humidity

- Ultra-violet (UV) radiation exposure

- Rain, hail, lightning

- Acoustic

- Fluid exposure

- Etc.

In-Space - Temperature (maximum and minimum)

- Temperature cycle, time at temperature

- Radiation (UV, Galactic Cosmic 

Radiation [GCR], Solar Particle Events 

[SPE])

- On-orbit debris

- Micro-meteoroid

- Vacuum

- Fluid exposure

- Etc.

Planetary Surface - Temperature (maximum and minimum)

- Temperature cycle, time at temperature

- Radiation (UV, GCR, SPE)

- Micro-meteoroid

- Lander induced ejecta

- Vacuum

- Fluid exposure

- Gravity value

- Etc.

The natural environments are very important and will impact many design factors. Absolute 

temperatures must be known and matched with loading history to define design load cases. 

Temperature cycling, vacuum and radiation environments can all influence the performance and 

degradation of certain materials. Micro-meteoroid and lander exhaust-induced debris 

environments will impact shielding design.

Natural Environment Knowledge Current Status: Good

Threat Environment

The threat environment refers to those external events that can cause damage to the structural 

system and pose a threat to structural safety. Threats to the structure will occur from the time of 

manufacturing through the end of operations (and end of life) on the planetary surface. A 

comprehensive set of threats must be compiled for each structural system, the probability of each 

threat occurring quantified, and the structural response and damage tolerance to each threat 
5/13

assessed. The desired level of safety, or acceptable level of risk, must be used in conjunction 

with the probability of occurrence and potential consequence (level of acceptable damage) to 

determine which threats will result in specific design requirements. Examples of possible threats 

for various time phases are listed in Table 2.

Table 2. Threat Examples by Mission Phase.

Manufacturing - Manufacturing defect (non-detectable by 

inspection)

- Tool drop, foreign object damage

- Etc.

Preparation and Transportation to 

Launch Site

- Handling damage (dropping, fork lift, tool 

drop, etc.)

- Foreign object damage

- Accident (transporter)

- Restraint failure

- Rain, hail, lightning, etc.

- Etc.

Integration with lander and launch 

vehicle and time on launch pad

- Handling damage (dropping, fork lift, tool 

drop, etc.)

- Foreign object damage

- Collision damage

- Restraint failure

- Rain, hail, lightning strike, etc.

- Etc.

Launch, In-Space - Rain, hail, lightning strike, bird strike, etc. on 

ascent

- Foreign object damage on ascent

- Collision (between stages)

- On-orbit debris

- Micro-meteoroid

- Lander restraint failure

- Etc.

Planetary Surface - Handling damage (manipulators, EVA, 

mobility chassis, robotic assistant, etc.) during 

unloading

- Restraint failure (mobility, handling)

- Micro-meteoroid

- Lander ejecta

- Foreign object damage

- Fire

- Collision (between mobility devices, between 

mobility device and fixed device)

- Roll over (mobility device)

- Collision (between manipulator and other 

device)

- Etc.
6/13

Threat Environment Knowledge Current Status:

Launch, In-Space, Planetary Surface: Poor

All Others: Good

Design Loads

The purpose of structure is to safely react and transfer loads within a system during its operation. 

To ensure a safe structure, the externally applied loads must be compiled for all mission phases, 

from the time the system is manufactured through the end of mission life. The applied loads are 

matched with consistent environments to define the design load cases. One example of an 

important interaction that must be captured when defining a load case, is between extreme 

temperatures (both hot and cold) and the applied loads. Since the performance of materials can 

change significantly with temperature, and extreme temperatures are possible on planetary 

surfaces, it will be especially important to include temperature conditions in each load case. 

Also, any stresses induced by environmental exposure (temperature for example) should be 

combined with the externally applied loads to define load cases.

Design loads fall into two major categories, limit and ultimate. Limit load is the maximum value 

expected to occur once in service during the life of the structural system. The structure must be 

able to sustain limit loads without any detrimental permanent deformation to the structure. At 

any load up to limit, deformation may not interfere with safe operation. Ultimate loads are 

obtained by multiplying limit loads by an appropriate factor of safety. The structure must be able 

to support ultimate loads without failure for a specified amount of time. Note that the factor of 

safety (FS) can be load dependant; FS = 1.5 is specified for mechanical loads, and FS = 2.0 is 

specified for pressure loads for example. However, FS is not intended to vary for different 

material/structural concepts or designs. Examples of possible external design loads to consider 

during typical life time phases are listed in Table 3.

Table 3. External design load examples by mission phases.

Test and Evaluation - Static proof loads - pressure

- Static proof loads – mechanical

- Vibration loads

- Acoustic loads

- Thermal loads

- Outfitting loads

- Combined loads

- Etc.

Preparation and Transportation to Launch Site - Gravity (1-g) at specified orientation

- Transportation loads (induced by truck, 

aircraft, etc.)

- Handling loads (cranes, fork lifts, etc.)

- Etc.

Integration with lander and launch vehicle and 

time on launch pad

- Gravity (1-g) at specified orientation

- Handling loads (cranes, fork lift, etc.)
7/13

- Outfitting loads

- Etc.

Launch, In-Space - Static mechanical loads (x-g’s) at 

specified orientations (launch vehicle)

- Acoustic loads

- Vibration loads

- Stage separation loads

- Thermal loads

- Pressure loads

- Cyclic/fatigue loads

- Etc.

Planetary Surface - Static mechanical loads (at appropriate

g level) in specified orientation

- Thermal loads

- Static pressure loads

- Handling loads

- Transportation loads

- Docking/Berthing loads

- Crash loads

- Vibration loads

- Etc.

Design Load Knowledge Current Status: Poor

Material Properties

A wide variety of materials are likely to be used for lunar surface structural systems. The major 

categories include metallic, polymer matrix composite (PMC) and structural soft goods (used in 

expandable or inflatable structures). Adhesives are considered a subset of PMC materials since 

most adhesives in a PMC system are derivatives of the matrix material. Structural soft goods can 

be divided into two major classes of material-product forms: bladders (which are twodimensional tension membranes), and restraint layers (uni-directional tension straps). The 

material properties required for design vary by material type, with examples listed in Table 4.

Table 4. Material property typical examples (used in design). (Note: should be end-of-life.)

Metals - Tension/compression moduli

- Shear modulus

- Tension/compression ultimate strength

- Yield strength

- Ultimate shear strength

- Bearing strength

- Fracture toughness

- Creep strength (temperature dependent)

- Density

- Poisson’s ratio
8/13

- Coefficient of thermal expansion

PMCs 

Note, because of their orthotropic nature, 

polymeric composite laminate values must 

be determined for both the x and y 

directions, with orientation of the laminate 

in the structural application accounted for 

in verifying compliance.)

- Open hole compression strain (strength)

- Open hole tension strain (strength)

- Compression-after-impact strain (strength)

- Bearing strength

- Tension/compression moduli

- Shear modulus

- Shear strength

- Poisson’s ratio

- Creep Strength (temperature dependent)

- Density

- Coefficient of thermal expansion 

(including through the thickness)

- Interlaminar shear strength

Structural Soft-goods (polymeric materials) - Bladder tension modulus

- Bladder ultimate strength

- Bladder tear strength

- Bladder creep strength (temperature 

dependent)

- Bladder density

- Bladder Poisson’s ratio

- Bladder coefficient of thermal expansion

- Strap tension modulus

- Strap ultimate strength

- Strap creep strength (temperature 

dependent)

- Strap density

- Strap coefficient of thermal expansion

In order to demonstrate design compliance it is required that the material properties, as they exist 

at the end of the system’s lifetime, be used in the evaluation. The natural environments the 

materials are exposed to, along with exposure duration are important factors that can cause 

degradation to the beginning-of-life properties. Different materials will be more or less 

susceptible to degradation when exposed to the full spectrum of environments. Lunar and Mars 

environments are within the experience base of most metallic materials. PMCs can be susceptible 

to degradation of properties when exposed to radiation, and their strength properties are likely to 

vary within the operational range of temperatures expected on a planetary surface. Since 

polymeric materials are also used for structural soft-goods, radiation exposure and temperature 

(at design loads) will also be important considerations for these materials. Creep at elevated 

temperatures might also be critical. In general, statistically based strength allowable values must 

be used when verifying design compliance, with the regulating authority specifying the use of Abasis, B-basis or S-basis allowables that are consistent with ensuring the required level of safety 

in the system. For PMCs, strength allowable values are both material and laminate dependent, 

and must be generated for each laminate used in the structure. Also, in general, notched 

allowables such as compression-after-impact, open-hole-tension, etc. are required for design. Un-
9/13

notched values are generally acceptable for laminate properties unrelated to strength such as 

modulus, Poisson’s ratio, and the coefficient of thermal expansion.

The details of a particular structural design will also impact the amount and types of exposures 

and must be determined for each specific design application. For example, if a composite 

structure is covered in multi-layer insulation, no degradation of the composite due to ultra-violet 

radiation exposure may occur. Similarly, if the pressure shell of a habitat is covered in layers 

made up of thermal insulation, radiation protection and micrometeoroid protection, the shell may 

be sufficiently insulated that it does not experience the extreme temperature excursions that can 

exist on the lunar surface.

Material Properties for Design Current Knowledge -

Metals: Good

Polymeric Composites: Fair

Structural Soft Goods: Poor

Structural Design Requirements

Structural design requirements are imposed on the structural system to ensure a desired level of 

safety. Requirements span a large number of categories and many or most of these requirements 

are generally independent of material/structural design implementation. That is, any design put 

forward must show compliance with the same set of requirements, ensuring that all proposed 

designs exhibit an equivalent level of safety. As new materials and structural concepts have been 

introduced, concept specific requirements have been developed. An example of a comprehensive 

set of structural design requirements is given in Table 5, taken from reference 3. The content of 

this table is meant to illustrate the broad scope of issues that must be addressed in a 

comprehensive set of structural design requirements. Obviously, many of the specific items will 

not apply to planetary surface structural systems. However, it is likely that many new 

requirements will have to be established that are particular to systems designed for a planetary 

surface and these requirements will parallel the intent of many of the items in the table. In the 

High Speed Research (HSR) Program, both metallic and PMC materials were evaluated. A wide 

variety of structural concepts that are not traditional (i.e. metallic, mechanically fastened 

stiffened skin) to commercial aircraft primary structure applications, were also considered. These 

included bonded PMC stiffened skin structure, bonded PMC sandwich structure, bonded metallic 

sandwich structure, and integrally machined/stiffened isogrid metallic structure, among others. 

Examples of material/structural concept specific requirements are also noted in the table.

Table 5. Structural Design Requirement Examples from sections in HSR document.

Section Heading Subsection Headings

General Requirements Design Service Objectives

Material Design Values (Note, not the 

properties themselves.)

Environmental Requirements

Stiffness Requirements

Airplane Level Structural Design Definitions: Limit Loads, Ultimate Loads, 
10/13

Requirements Deformations, Load and Temperature 

Redistribution, Transient Response

Weights for Structural Design

Design Airspeeds

Symmetrical Maneuver Criteria

Gust Criteria

Rolling Maneuver Criteria

Yawing Maneuver Criteria

Engine Out Maneuver Criteria

Engine Inlet Unstart Maneuver Criteria

Ground Loads Criteria: Landing Impact, 

Ground Handling Conditions

Nacelle Loads Criteria

Fuselage Pressure Loads Criteria

Fuel Tank Load Criteria

Ditching and Crash Load Criteria

Damage Tolerance Loads Criteria

Fatigue Loads Criteria

Material and Structural Requirements General Material and Structural Concept 

Requirements:

- Polymer Matrix Composite 

Requirements

- Metallic Materials Requirements

- Hybrid Titanium/PMC Laminate 

Requirements

- Skin-Stringer Requirements

- Honeycomb Sandwich Requirements

Strength Requirements

Stability Requirements

Bolted Joint Requirements

Bonded Requirements

Repair Requirements

Handling Requirements, Metallic Structure

Handling Requirements, Non-Metallic 

Structure

Minimum Gage Requirements

Thermal Insulation Requirements

Durability and Damage Tolerance 

Requirements

Durability Objectives: Metals Durability, 

Composite Durability, Hybrid Laminate 

Durability

Sonic Fatigue Requirements

Panel Flutter Requirements

Damage Tolerance Requirements:

- Metallic Structure

- Composite Structure
11/13

- Hybrid Laminate Structure

Ground Hail Zone and Requirements

Runway Debris Zones and Requirements

Lightning Strike Zones and Requirements

In-Flight Discrete Source Damage 

Requirements

The first two categories of requirements (General and System [Airplane] Level Structural 

Design) apply to all material/structural designs and a significant number of these requirements 

deal with design load cases. One can also see many potential parallels between the categories for 

aircraft structure and lunar surface structure. For example, instead of In-Flight discrete source 

damage, a planetary surface system must consider micrometeoroid and lander ejecta damage 

sources.

The item “Minimum Gage Requirement” is an example of one that may be especially important 

for exploration planetary surface structures. Current structural mass estimation that has been 

performed for the Lunar Habitat pressure shell (see reference 1) relied on a single load case 

(internal pressure), with isolated margin-of-safety checks performed for a launch load case. The 

structural strength sizing required for this single load case resulted in very thin sandwich 

facesheets. As a result, the minimum gage criteria from reference 3 was applied to the structure. 

Although sizing with a single load case cannot be considered valid, the fact that a minimum gage 

constraint had to be imposed can be used to argue that defining the minimum gage for lunar 

surface structural applications is extremely important, since minimum gage will dictate the 

absolute minimum mass possible. The minimum gage value (which is material and structural 

concept dependent) for a structure is based on a damage tolerance evaluation, which requires a 

comprehensive assessment of the threat environment, the natural environment, load cases and 

material properties.

Structural Design Requirements Knowledge Current Status -

Metals: Poor

Polymeric Composites: Poor

Structural Soft Goods: Poor

Design Compliance

An evaluation must be performed on the structural system to demonstrate compliance such that 

every design requirement is met at each critical loading condition. Compliance can be 

accomplished through a combination of test and analysis. Structural analysis may be used only if 

the structure conforms to that for which experience has shown the analysis method to be reliable. 

The regulating authority may require ultimate load tests in cases where limit load tests are 

inadequate. A Design Compliance document will detail the PSEs in the system, acceptable 

analysis methods and equations, and types and degree of testing required. A detailed test plan 

describing test specimens, boundary conditions, loading histories, pass/fail criteria, etc. would 

also be developed. Demonstrating (through analysis and test) successful compliance to all 

structural design requirements would result in acceptance of the structural system for service.
12/13

Design Compliance Current Status of knowledge -

Metals: Poor

Polymeric Composites: Poor

Structural Soft Goods: Poor

Approach For Creating Necessary Design Data

At the end of each of the sections in “Design Requirements and Supporting Information”, an 

overall status has been estimated. This status represents the author’s opinion of the state-of-theart in each area. Successfully designing planetary surface structural systems requires that the 

knowledge in each category exist, be comprehensive, and have high integrity. Based on the 

author’s assessment, planetary surface systems for human exploration lack much of the 

foundational information that is required to design these structural systems. In order to begin 

addressing this deficiency, two potential tasks were outlined and submitted during the 

Technology Prioritization Process completed by LSS in December 2008:

1. Long term durability for polymeric composite materials and damage tolerance for 

metallic and polymeric composite structures; and,

2. Long term durability and damage tolerance for materials/structures for Inflatable 

Structures.

A detailed description of information needs and the state of knowledge pertaining to these two 

technology tasks has been described in this document.

In order to begin designing exploration planetary surface structural systems, the information and 

data in each of the major areas outlined under the “Design Requirements and Supporting 

Information” section must be developed, beginning with those areas where current knowledge is 

deemed to be Poor. The approach would be executed in approximately the same order in which 

those areas are discussed in this paper, with some activities proceeding in parallel. Major 

activities during the first several years would include:

1. collecting information and data,

2. defining the system structural concepts for which design must be performed,

3. identifying missing data and developing plans to obtain that data (through analysis and/or 

test),

4. performing trade studies to identify major material/structural concepts that could be 

applied to each system concept,

5. reconciling trade study and data development plans to identify required detailed tests and 

analyses,

6. performing the detailed tests and analyses,

7. compiling the planetary surface structural systems requirements and compliance 

document.
13/13

Concluding Remarks

The Lunar Surface Systems Project developed system concepts that would be necessary to 

establish and maintain a permanent human presence on the Lunar surface. A variety of specific 

system implementations were generated as a part of the scenarios, some level of system 

definition was completed, and masses estimated for each system. Because the architecture 

studies generally spawned a large number of system concepts and the studies were executed in a 

short amount of time, the resulting system definitions had very low design fidelity. The results of 

these low fidelity studies were insufficient to identify critical material and structures technology 

development needs. In particular, technology development needs cannot be inferred from 

concept definitions because those needs are particular to a system implementation (and thus 

change with implementation concept), and that implementation is dependent on, at a minimum, a 

conceptual design. This paper describes the broad steps that are required to develop and field a 

particular structural system with the steps being: 1) Define Requirements, 2) Develop the Design 

and 3) Demonstrate Compliance of the Design with all requirements. Completing this process is 

important because a comprehensive set of Structural Design Requirements does not currently 

exist for systems that must survive and operate on the lunar and other planetary surfaces. This 

paper also: outlines and describes in detail the information and data that are required to establish 

structural design requirements; outlines the information that would comprise a planetary surface 

system Structures Requirements document; provides a status of the data sets needed to establish 

requirements (most are currently incomplete or missing), and; outlines an approach for 

developing the necessary data and information. The resulting plan is intended to serve as the 

framework for implementing an exploration planetary surface structural systems technology 

development process.

References

1. Dorsey, John T.; Wu, K. C.; and Smith, Russell W.: Structural Definition and Mass 

Estimation of Lunar Surface Habitats for the Lunar Architecture Team Phase 2 (LAT-2) 

Study. Presented at the ASCE Earth and Space 2008 Conference, Long Beach CA, March 

3 – 5, 2008.

2. Standard For Lifting Devices and Equipment. NASA-STD-8719.9, May 9, 2002.

3. High-Speed Research Program, Airframe Materials & Structures: HSR Design 

Requirements, Objectives and Compliance Document, May 1996. NASA Contract 

NAS1-20220, Task 28, Boeing Commercial Airplane Group.
REPORT DOCUMENTATION PAGE Form Approved

OMB No. 0704-0188

2. REPORT TYPE 

Technical Memorandum

 4. TITLE AND SUBTITLE

Exploration Planetary Surface Structural Systems: Design Requirements 

and Compliance

5a. CONTRACT NUMBER

 6. AUTHOR(S)

Dorsey, John T.

 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

NASA Langley Research Center

Hampton, VA 23681-2199

 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

National Aeronautics and Space Administration

Washington, DC 20546-0001

 8. PERFORMING ORGANIZATION

 REPORT NUMBER

L-20039

10. SPONSOR/MONITOR'S ACRONYM(S)

NASA

13. SUPPLEMENTARY NOTES

12. DISTRIBUTION/AVAILABILITY STATEMENT

Unclassified Unlimited

Subject Category 18 

Availability: NASA CASI (443) 757-5802

19a. NAME OF RESPONSIBLE PERSON

STI Help Desk (email: help@sti.nasa.gov)

14. ABSTRACT

The Lunar Surface Systems Project developed system concepts that would be necessary to establish and maintain a permanent 

human presence on the Lunar surface. A variety of specific system implementations were generated as a part of the scenarios, 

some level of system definition was completed, and masses estimated for each system. Because the architecture studies 

generally spawned a large number of system concepts and the studies were executed in a short amount of time, the resulting 

system definitions had very low design fidelity. This paper describes the development sequence required to field a particular 

structural system: 1) Define Requirements, 2) Develop the Design and 3) Demonstrate Compliance of the Design to all 

Requirements. This paper also outlines and describes in detail the information and data that are required to establish structural 

design requirements and outlines the information that would comprise a planetary surface system Structures Requirements 

document.

15. SUBJECT TERMS

certification, compliance, design, planetary exploration, structural systems, structures

18. NUMBER

 OF 

 PAGES

18

19b. TELEPHONE NUMBER (Include area code)

(443) 757-5802

a. REPORT

U

c. THIS PAGE

U

b. ABSTRACT

U

17. LIMITATION OF 

 ABSTRACT

UU

Prescribed by ANSI Std. Z39.18

Standard Form 298 (Rev. 8-98)

3. DATES COVERED (From - To)

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

5d. PROJECT NUMBER

5e. TASK NUMBER

5f. WORK UNIT NUMBER

431731.04.02.04 

11. SPONSOR/MONITOR'S REPORT

 NUMBER(S)

NASA/TM-2011-217159

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PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS.

1. REPORT DATE (DD-MM-YYYY)

01- 06 - 2011