March 2010 

NASA/TM-2010-216210 

Ares I-X Flight Test Vehicle: 

Stack 1 Modal Test 

Ralph D. Buehrle, Justin D. Templeton, Mercedes C. Reaves, Lucas G. Horta, and James L. Gaspar 

Langley Research Center, Hampton, Virginia 

Paul A. Bartolotta 

Glenn Research Center, Cleveland, Ohio 

Russel A. Parks and Daniel R. Lazor 

Marshall Space Flight Center, Huntsville, Alabama 
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March 2010 

NASA/TM-2010-216210 

Ares I-X Flight Test Vehicle: 

Stack 1 Modal Test 

Ralph D. Buehrle, Justin D. Templeton, Mercedes C. Reaves, Lucas G. Horta, and James L. Gaspar 

Langley Research Center, Hampton, Virginia 

Paul A. Bartolotta 

Glenn Research Center, Cleveland, Ohio 

Russel A. Parks and Daniel R. Lazor 

Marshall Space Flight Center, Huntsville, Alabama 
Available from: 

NASA Center for AeroSpace Information 

7115 Standard Drive 

Hanover, MD 21076-1320

443-757-5802 

Acknowledgments 

Thanks go to Winifred Feldhaus of NASA Langley Research Center for her assistance with finite 

element model development. The test execution phase at Kennedy Space Center (KSC) could 

not have been done without the support of many individuals. Special thanks go to the KSC 

instrumentation team led by Frank Walker. Logistics and test hardware integration went 

smoothly due to the dedicated KSC crew that included Russ Brucker, Trip Healey, Stephanie 

Heffernan, Teresa Kinney, Todd Reeves, Kara Schmitt, Mark Tillett, and Jim Wiltse. Lastly, 

thanks to our independent verification team of Jeff Lollock, Ryan Tuttle, and Joshua Hwung 

from Aerospace Corporation. 
Table of Contents

1.0 Introduction 6

2.0 Pre-Test Planning 8

2.1 Test Requirements 8

2.3 Pre-Test Analysis 9

3.0 Test Description 13

3.1 Test Article 13

3.2 Test Instrumentation 15

3.3 Excitation Systems 19

3.4 Data Acquisition System 21

4.0 Stack 1 Test Operation and Data Analysis 22

4.1 Summary of Tests 22

4.2 Random Data Analysis 30

4.3 Sine Sweep Data Analysis 36

4.4 Impact Data Analysis 38

5.0 Experimental Modal Analysis Results 42

6.0 Summary 43

References: 44

Appendix A: Acronyms and Abbreviations 46

Appendix B: Equipment List 48

Appendix C: Instrumentation Setup and Channel Mapping 51

Appendix D: Data Acquisition Log 59

Appendix E: Test Mode Shapes 62

5
6 

Abstract 

Ares I-X was the first flight test vehicle used in the development 

of NASA’s Ares I crew launch vehicle. The Ares I-X used a 4-

segment reusable solid rocket booster from the Space Shuttle 

heritage with mass simulators for the 5th segment, upper stage, 

crew module and launch abort system. Three modal tests were 

defined to verify the dynamic finite element model of the Ares I-X 

flight test vehicle. Test configurations included two partial stacks 

and the full Ares I-X flight test vehicle on the Mobile Launcher 

Platform. This report focuses on the second modal test that was 

performed on the middle section of the vehicle referred to as Stack 

1, which consisted of the subassembly from the 5th segment 

simulator through the interstage. This report describes the test 

requirements, constraints, pre-test analysis, test operations and 

data analysis for the Ares I-X Stack 1 modal test. 

1.0 Introduction 

The 327 foot 1.8 million-pound Ares I-X launch vehicle [1] is shown in Figure 1. Ares I-X 

consists of a 4-segment reusable solid rocket motor from the Space Shuttle heritage with mass 

simulators for the 5th segment, upper stage, crew module (CM) and launch abort system (LAS). 

Ares I-X was successfully launched on October 28, 2009. This was the first flight test for 

NASA’s Ares I crew launch vehicle. Flight test data will provide important information on 

ascent loads, vehicle control, separation, and first stage reentry dynamics. 

As part of hardware verification for Ares I-X, a series of modal tests were designed to verify the 

dynamic finite element model (FEM) used in loads assessments and flight control evaluations. 

The first three free-free bending mode pairs were defined as the target modes for the modal test 

based on the flight control requirements. Since a test of the free-free vehicle configuration was 

not practical within the projects constraints, calibration of the FEM was done using modal test 

data for three configurations in the nominal KSC integration flow. The first of these modal tests 

was performed in May 2009 on the Stack 5 subassembly [2], which included the topmost 

hardware from the Spacecraft Adapter Simulator to the Launch Abort System Simulator as 

shown in Figure 2. The second test was performed in July 2009 on the Stack 1 hardware, which 

included the center section from the 5th Segment Simulator through the Interstage. Finally, the 

fully integrated Ares I-X flight test vehicle (FTV) mounted to the Mobile Launcher Platform 

(MLP) was tested in August 2009 [3]. 

This report focuses on the Stack 1 modal test. The requirements are derived from the free-free 

bending target modes of the FTV [4]. Based on these requirements, FEM pre-test analysis is 

used to define the response transducer and shaker locations. Project constraints on 

instrumentation numbers and vehicle accessibility are also discussed as part of the 

transducer/shaker placement studies. Schedule constraints required that the team conduct the 

tests and verify the sufficiency of the data in a short three-day test period. Details of the modal 

test planning, setup, operation, and results are described. Comparisons between pre-test 

predictions and test data are provided in Horta [5].
7 

 

Figure 1. Ares I-X Flight Test Vehicle [1] 
8 

Figure 2. Ares I-X Subassembly Modal Test Configurations 

 

2.0 Pre-Test Planning 

2.1 Test Requirements 

The Stack 1 modal test was meant to provide an early assessment of FEM adequacy for the 

subassembly. The project emphasized minimal instrumentation to characterize the bending modes and 

did not provide hard limits on test/analysis orthogonality metrics. Initially, the goal prior to conducting 

the pre-test analysis was for approximately 20 sensor locations with biaxial accelerometers for capturing 

the bending modes. To minimize impact to the program schedule and cost, test durations and 

configurations were restricted to what was available during the normal vehicle integration flow. 

Because no special provisions were made for testing, the stack 1 subassembly was tested while shimmed 

to the floor of the build-up stand in High Bay 4 of the Vehicle Assembly Building (VAB). Testing in 

the build-up stand of the VAB added two significant constraints to the test setup. First, shaker mounting 

was restricted to locations accessible from existing facility platforms. Second, the boundary condition 
9 

was unknown and would need to be compensated for in the analysis. Early in the planning stage, the 

test team recognized the risk associated with unknown boundaries and proceeded with an effort to 

correct for boundary interface compliance [6], and planned for additional measurements across the 

boundaries. The boundary condition will be further described in the Test Description section. 

For flight control, the first three free-free bending mode pairs of the flight test vehicle were critical. 

Based on these modes, a traceability study [4] was used to define the target modes for the subassembly 

tests. These target modes will be described in the Pre-Test Analysis section. 

2.3 Pre-Test Analysis 

The Stack 1 configuration consists of the 5th segment simulator, forward skirt, forward skirt extension, 

frustum, interstage-1, and interstage-2 as shown in Figure 3. The free end of the 5th segment simulator 

was shimmed at 12 locations to the buildup stand supports. Additional photographs of the interface will 

be provided in the Test Description section. For the pre-test analysis, the boundary interface was 

modeled with springs having a nominal stiffness of 1X107 lb/in at the shim locations. Instrumentation 

across the boundary was planned to aide in assessing the true interface compliance. Table 1 shows the 

FEM pretest predictions with the target modes highlighted. The corresponding mode shapes are shown 

in Figure 4. 

Based on these target modes, the effective independence technique [7] along with engineering judgment 

was used to determine the sensor and shaker locations. The resulting measurement locations are shown 

on Figure 5. Figure 5 also shows the two shaker locations that were selected based on the constraint of 

utilizing existing facility platforms for shaker mounting. The 59574 degree of freedom (DOF) FEM was 

reduced to an 88 DOF test model. The corresponding cross-orthogonality between the reduced model 

(corresponding to the test instrumentation set) and the full model is used to assess the adequacy of the 

test instrumentation set as shown in Figure 6. The correlation for the first six modes is consistent with 

goals of having >0.9 on the diagonal and <0.1 on the off-diagonal terms. This implies that the test 

instrumentation set is suitable for capturing the first six modes based on the cross-orthogonality metric. 

The modes with bending (1, 2, 6, 7, and 8) are of primary interest for traceability to the flight test 

vehicle configuration [4]. Although it is anticipated that modes 7 and 8 will not meet crossorthogonality goals, qualitative comparisons of mode shapes and frequency response function data will 

be used to evaluate these modes. This was due to the use of minimal instrumentation and a late update 

to the FEM after instrumentation installation had begun. Adequate time prior to testing was not 

available to reassess the instrumentation placement due to the FEM changes. The free-edge at the top of 

interstage-2 also resulted in significant shell motion (see Figure 4) making it difficult to obtain adequate 

spatial resolution with the limited instrumentation. 
10

Figure 3. Stack 1 test configuration 
11

Table 1 Pre-Test Analysis Modes for Stack 1 

Mode No. Frequency

(Hz)

Mode Description

1 4.07 Stack 1st Bending

2 4.14 Stack 1st Bending

3 16.2 Interstage 2N shell mode

4 16.7 Interstage 2N shell mode

5 17.3 Torsion

6 22.0 Interstage 3N shell mode,

coupled with stack 2nd Bending

7 22.7 Interstage 3N shell mode,

coupled with stack 2nd Bending

8 23.3 Interstage 3N shell mode,

coupled with stack 2nd Bending

Figure 4. FEM Pre-Test Analysis Mode Shapes for Stack 1 
12

 

 Figure 5. Stack 1 sensor/shaker locations with cylindrical coordinate system in red 

 

Figure 6. Stack 1 cross-orthogonality 
13

3.0 Test Description

3.1 Test Article 

Testing of the 71-foot tall and approximately 150-thousand pound Stack 1 configuration was 

performed in the build-up stand of High Bay 4 in the VAB as shown in Figure 7. The clevis 

joint at the free-end of the 5th segment was shimmed at twelve locations to the VAB build-up 

stand support as shown in Figure 8. This complicated boundary condition has the shims (shown 

in red) resting on pads that are attached to an I-beam structure (shown in blue) that is in turn 

resting on concrete piers (shown in green) built into the VAB floor. As a reference, shim 4 

aligns with the 90-degree orientation of the flight test vehicle coordinate system. Prior to 

initiating the assembly of Stack 1, the twelve shims were leveled to within 1/16-inch. When only 

the 5th segment was installed, five of the shims (locations 2, 5, 6, 8, and 11) could be moved by 

hand indicating no contact at these locations. The gaps were measured and documented in 

Figure 8. After the addition of the frustum and interstage components, there was contact at all 

twelve of the shim locations. As shown in figures 9 and 10, several sets of accelerometers were 

placed across the boundary in an effort to characterize the boundary condition. 

Figure 7. Stack 1 modal test setup with shaker 2 circled in red 
14

Figure 8. Shim locations (in red) showing gaps with only 5th segment component mounted 

 

Figure 9. Shim plate 4, Accelerometer locations 36 
15

Figure 10. Shim plate 5, Accelerometer locations 24, 28, and 32 

3.2 Test Instrumentation 

Capacitive accelerometers (PCB Model 3701GFA3G and 3701M 15) were used to measure the 

dynamic response of the test article. Accelerometer and shaker locations for the Stack 1 

configuration are shown in Figure 5 and listed in Table 2. Due to the significant shell type 

response in the target modes, a cylindrical coordinate system was used for the measurements as 

shown in Figure 5. Accelerometer installation was performed according to KSC Work Plan FAGIE-0020, Ares-IX Stack 1 Modal Test-Ground Instrumentation Support. Representative 

photographs of the accelerometer installations are provided in Figures 9-11. To aide in the 

investigation of some local response issues for the Flight Termination System (FTS) and First 

Stage Avionics Module (FSAM), accelerometer locations 46-49 were added after the first test 

day as shown in Figures 12-14. 
16

 

Table 2 As-installed Accelerometer Locations 

Sensor 

Location 

Radial1

(in)

Angle1

(Degrees)

Z

1

(FTV X) 

(in)

Description Measurement 

Axis

1 108.25 30 1859.5 Interstage-2 R, T

2 108.25 60 1858.7 Interstage-2 R, T

3 108.25 105 1860 Interstage-2 R, T

4 108.25 150 1859.2 Interstage-2 R, T

5 108.25 195 1860.5 Interstage-2 R, T

6 108.25 240 1858.2 Interstage-2 R, T

7 108.25 300 1860 Interstage-2 R, T

8 108.25 345 1860.5 Interstage-2 R, T

9 108.25 30 1939.2 Interstage-1 R, T

10 108.25 135 1938.5 Interstage-1 R, T

11 108.25 192 1937.5 Interstage-1 R, T

12 108.25 225 1939.3 Interstage-1 R, T

13 108.25 348 1937.2 Interstage-1 R, T

14 72.79 195 2137 Fwd Skirt Extension R, T

15 72.79 225 2137 Fwd Skirt Extension R, T

16 72.79 40 2335.9 5

th Segment; Shaker -1 R, T

17 72.79 112.5 2328.3 5

th Segment R, T

18 72.79 140 2336.4 5

th Segment; Shaker - 2 R, T

19 72.79 210 2327.7 5

th Segment R, T

20 72.79 232.5 2328.1 5

th Segment R, T

21 72.79 300 2327.7 5

th Segment R, T

22 72.79 330 2327.2 5

th Segment R, T

23 72.79 45 2601.6 5

th Segment side of ground interface in-line with 31 R,T,Z

24 72.79 135 2601.6 5

th Segment side of ground interface in-line with32 R,Z

25 72.79 225 2601.6 5

th Segment side of ground interface in-line with 33 R,T,Z

26 72.79 315 2601.6 5

th Segment side of ground interface in-line with 34 R,Z

27 72.79 45 2592.5 5

th Segment adapter ring in-line with 23 Z

28 72.79 135 2592.5 5

th Segment adapter ring in-line with 24 Z

29 72.79 225 2592.6 5

th Segment adapter ring in-line with 25 Z

30 72.79 315 2592.4 5

th Segment adapter ring in-line with 26 Z

31 72.79 47 2602.9 Ground shim plate 3 R,T,Z

32 72.79 133 2602.9 Ground shim plate 5 R,Z

33 72.79 228 2602.9 Ground shim plate 9 R,T,Z

34 72.79 313 2602.9 Ground shim plate 11 R,Z

35 72.79 0 2602.9 Ground shim plate 1 Z

36 72.79 90 2602.9 Ground shim plate 4 Z

37 72.79 180 2602.9 Ground shim plate 7 Z

38 72.79 270 2602.9 Ground shim plate 10 Z

39 0 0 1971 IS-1 Platform R,T,Z

40 54 315 1971 IS-1 Platform T,Z

41 54.6 45 1971 IS-1 Platform Z

46 45 150 2480 FSAM 27 Inches from Center Ring-added 7/14/09 -R, T, Z

47 21.25 150 2480 FSAM 3.25 Inches from Center Ring added 7/14/09 -R, T, Z

48 66.79 210 2570 FTS battery added 7/14/09 -R,, -Z

49 69.79 65 2535 FTS added 7/14/09 -R,, -Z

Note+: Cylindrical coordinate system referenced to FTV coordinate system: Nominal radius from vehicle centerline; 

0 degrees is aligned with +Z-axis and 270 degrees with +Y-axis of FTV coordinate system; Z-axis is aligned with 

FTV X-axis. 
17

Figure 11. Accelerometer installation on interstage-1 platform 

Figure 12. Accelerometer installation on FSAM support plate 
18

Figure 13. FTS battery mount, accelerometer location 48 

Figure 14. FTS mounting plate, accelerometer location 49 
19

3.3 Excitation Systems 

Two MB Dynamics Model 250 electro-dynamic shakers were used to provide excitation to Stack 

1 as shown in Figures 15-17. The shakers were attached to a wooden fixture (shown in white) 

that was bolted to the facility platform using through bolts at two handrail post locations. To 

impart axial loads while minimizing lateral excitation, each shaker was attached to the test article 

through a 1⁄4-28 threaded stinger rod. At the point of load application, the stinger rod was 

threaded into an impedance sensor/adapter plate arrangement as shown in Figure 17. These 

adapter plates were attached to the test article with dental cement. 

The shakers were operated simultaneously for Multiple Input Multiple Output (MIMO) random 

testing. Several sine sweeps using a single shaker were also performed. The idle shaker was 

disconnected from the test article during the sine sweeps. In addition to the shaker test, impact 

tests were performed for several excitation positions with all response data recorded 

simultaneously. A PCB Piezotronics Model 086B20 hammer was used for impact testing. 

 Figure 15. Shaker 1 setup 
20

Figure 16. Shaker 2 setup 

Figure 17. Shaker 1 impedance head and adapter plate setup 
21

3.4 Data Acquisition System 

The 112-channel data acquisition system (DAS) consisted of seven 16 channel 24-bit VXI data 

acquisition cards in a single 13-slot VXI mainframe chassis. Sufficient channels were available 

to simultaneously sample and record all data. A 16-bit VXI source card in the same chassis 

provided separate source signals for the excitation system. A Firewire interface card allowed the 

DAS to be controlled by a data acquisition computer running m+p International’s Smart Office 

Analyzer software. During the test, the software calculated the FRFs from the acceleration and 

force measurements. For all tests, time and FRF data was stored directly to the computer’s hard 

drive as it was acquired. After each test, the FRFs were exported to a universal file format and 

supplied to the test team for on-site modal parameter estimation. 

A picture of the signal conditioner rack and data acquisition rack as they were configured for the 

modal test is shown in Figure 18. The signal conditioner rack contained four filters that were 

used to filter the source signals before they reached the excitation system. The signal conditioner 

rack also contained the seven signal conditioners used during the test. All of these signal 

conditioners, plus the filters and the VXI chassis were powered by an Uninterruptible Power 

Supply (UPS) in the bottom of the signal conditioner rack. A separate UPS located in the bottom 

of the data acquisition rack was used to power the computer. This isolated the typically noisy 

computer power supply from the rest of the DAS equipment. For a complete list of the 

equipment, see Appendix B. 

The majority of the signal conditioner channels were routed directly to the data acquisition cards 

in the VXI chassis using custom-built cables (dark gray cables). BNC cables to patch panels at 

the top of the data acquisition rack connected the rest of the channels. These patch panels were 

then connected to the data acquisition cards at the bottom of the rack. For more information on 

the connections from the instrumentation to the data acquisition system, see the channel mapping 

in Appendix C. 
22

Figure 18. Data acquisition system configuration

4.0 Stack 1 Test Operation and Data Analysis 

4.1 Summary of Tests 

The modal test was performed by applying a measured excitation force to the test article and 

measuring the acceleration response at selected locations. The FRFs were calculated as the ratio 

of the acceleration response to the input force. Modal parameters (natural frequencies, damping 

factors, and mode shapes) were then estimated from the FRFs. Both the measured FRF data and 

modal parameter estimates were compared with the pre-test predictions to ensure that sufficient 

data was acquired to capture the target modes of interest. The primary datasets for modal 

parameter estimation were FRFs for multi-input random excitation at several force levels. Sine 

sweeps using a single shaker were used to check for linearity of selected modes with respect to 

force level. In addition, impact testing was used to provide additional data for model 

verification. 

The test data that was acquired during the Stack 1 modal test is listed in table 3. An 

accompanying data acquisition log is included in Appendix D. Preliminary testing was 

performed on July 11 and consisted of Tests SS1-1 through SS1-5. Integration activities were 

ongoing during these preliminary tests so the data will be influenced by personnel activities. 

Data

Acquisition

Rack

Signal

Conditioner

Rack
23

Evaluation of the preliminary data was used to confirm shaker setup, preferred excitation signal, 

and accelerometer response characteristics. A review of the preliminary data identified the 

swapping of data channels 8R and 8T. It was also evident that residual effects from shell modes 

(>40 Hz) at the shaker input locations were resulting in high modal response estimates at the 

drive points (see Figure 19). For future tests of cylindrical structures, excitation along a 

tangential direction should be considered as a means of minimizing this effect. It was also 

observed that the preliminary mode frequencies were significantly lower than the pre-test 

predictions, which was attributed to the boundary conditions. 

The official test days were July 13 and 15, 2009 and included tests SS1-6 through SS1-17. 

Several random tests at various force levels, frequency resolutions and excitation bandwidths 

were evaluated to try to obtain quality frequency response functions. Sine sweep tests at three 

force levels were used to examine the linearity of the first mode in each axis. In addition, a sine 

sweep over the 14.1 to 30 Hz range was conducted to try and better resolve the modes in this 

range. The response of all transducers was also measured for 11 different impact locations. 

These locations did not correspond to sensor response locations so a brief description of these 

impact locations is included in Table 4 and shown in Figures 20-28. Locations 52 through 56 

were acquired for evaluation of local response of the IS-1 platform, FSAM, and FTS 

components. Due to available platforms, the shakers were restricted to a relatively low position 

on the Stack 1 assembly. Therefore, several impact locations (denoted as 50, 51 and 57) were 

used in an effort to resolve some of the bending/shell modes with significant participation at the 

top of Stack 1. 

Figure 19. Drive point FRF for test SS1-14 showing dominant out of band modes 

Frequency - Hz

Log g/lbf Phase deg

0 20 40 60 80 100

100μ

100m

10m

1m

0 20 40 60 80 100

-200

200

100

50

0

-50

-100

FRF(SS1.16.R,SS1.16.R-) 

42.055 Hz
24

Table 3 Super Stack 1 Modal Test Datasets 

Test Run Type Level Direction(s) Range Resolution

SS1-1 n/a Hand Shake Test n/a n/a 1 - 50 Hz 0.016 Hz

SS1-2 n/a Burst Random (50%, 20 avg) 20 lb-rms 16R-, 18R- 1 - 50 Hz 0.016 Hz

SS1-3 n/a Burst Random (50%, 20 avg) 20 lb-rms 16R-, 18R- 1 - 50 Hz 0.016 Hz

SS1-4 n/a Random (20 avg) 20 lb-rms 16R-, 18R- 0 - 50 Hz 0.016 Hz

SS1-5 n/a Impact n/a 41XFTV, 2R 0 - 50 Hz 0.125 Hz

1 0.016 Hz

2 0.0078 Hz

SS1-7 n/a Random (16 block, 31 avg) 50 lb-rms 16R-, 18R- 0 - 25 Hz 0.016 Hz

SS1-8 n/a Ambient Noise n/a n/a 0 - 25 Hz 0.016 Hz

SS1-9 n/a Random (16 block, 31 avg) 40 lb-rms 16R-, 18R- 0 - 40 Hz 0.016 Hz

2 50 lb-pk

3 100 lb-pk

4 150 lb-pk

1 50 lb-pk

2 100 lb-pk

3 150 lb-pk

SS1-12 n/a Random (16 block, 31 avg) 100 lb-rms 16R-, 18R- 0 - 25 Hz 0.0078 Hz

SS1-13 n/a Ambient Noise n/a n/a 0 - 100 Hz 0.0078 Hz

SS1-14 n/a Random (16 block, 31 avg) 50 lb-rms 16R-, 18R- 0 - 100 Hz 0.0078 Hz

SS1-15 n/a Random (16 block, 31 avg) 50 lb-rms 16R-, 18R- 0 - 25 Hz 0.0078 Hz

SS1-16 n/a Impact n/a 11 locations 0-50/100 Hz 0.125 Hz

1 50 lb-pk

2 20 lb-pk

SS1-6

SS1-10

SS1-11

SS1-17 Sine Sweep (0.75 Hz/min)

Random (16 block, 31 avg) 20 lb-rms 16R-, 18R- 0 - 25 Hz

Sine Sweep (0.02 Hz/min)

Sine Sweep (0.03 Hz/min)

16R18R1.91 - 

2.13 Hz

1.54 - 

1.72 Hz

n/a

n/a

16R- 14.1 - 30 Hz n/a
25

Table 4 Super Stack 1 Impact Locations for Test SS1-16 

Point and Direction Description

50 R- Top of Frustum at 90 from outside

51 R- Top of Frustum at 270 from outside

52 X (FTV X) (See Figure 20) IS-1 platform on outer edge of platform along I-beam 

at 225 (two people inside but not on platform)

52 T- (See Figure 21) IS-1 platform on outer edge of platform along I-beam 

at 225 (two people inside but not on platform)

52 R- (See Figure 22) IS-1 platform closeout beam at 270 (two people 

inside but not on platform)

53 X- (FTV X) (See Figure 23) FSAM base plate at 120

54 R (See Figure 24) Below FTS on stiffening ring radial at 65

54 X (FTV X) (See Figure 25) Top ring frame about 10‖ above FTS

55 R- (See Figure 26) 122‖ up from shims at ~ FSAM elevation and 150

56 R- (See Figure 27) 84‖ up from shims at ~FTS location and 65

57 R (See Figure 28) Top of frustum at 0 (two people inside)

Figure 20. Impact on IS-1 platform on outer edge along I-beam at 225 (52X) 
26

Figure 21. Impact on IS-1 platform on I-beam at 225 (52T-) 

Figure 22. Impact radial on closeout beam for IS-1 platform at 270 (52R-) 
27

Figure 23. Impact on FSAM base plate beam at 120 (53X-) 

Figure 24. Radial impact on stiffening ring below FTS (54R) 
28

Figure 25. Impact on ring frame above FTS (54X) 

 Figure 26. Exterior impact 122” up from shims (FSAM elevation) and 150 (55R-) 
29

Figure 27. Exterior impact 84” up from shims at ~FTS location and 65 (56R-) 

Figure 28. Impact from inside at top of frustum and 0 (57R) 
30

4.2 Random Data Analysis 

The random excitation data sets were the primary data for mode shape estimation and model 

calibration. In this section, the data quality from these tests is evaluated based on the FRF, 

coherence, reciprocity, and input force characteristics. Measurement linearity with force 

amplitude is also examined for the three random input test levels. 

Several sets of random data were acquired with various resolutions, frequency ranges and force 

levels during the first test day. After evaluation of this data, the final sets of random data for 

modal parameter estimation were acquired with a resolution of 0.0078 Hz. Several of the earlier 

data sets were acquired using a lower resolution, but these were more difficult to curve fit. Two 

other data sets used higher sample rates to investigate higher frequency phenomena, but this also 

spread the force out over a larger frequency range, resulting in less force being concentrated at 

the target modes. 

Sample FRF and coherence data from the 50 lb-rms random test SS1-15 is shown in Figures 29 

and 30 below. The blue curves representing the drive point FRFs show the peaks associated with 

the first bending modes around 2 Hz, but the higher frequency response is dominated by residual 

effects from shell modes above the frequency range of interest. This dominant high frequency 

shell mode did not affect any other measurements besides the drive points in the radial direction. 

FRFs for radial and tangential measurement points near the top of the structure (red and green 

curves) show the 1st bending modes as well as higher order modes above 10 Hz. The multiple 

coherence functions (cyan, magenta, and yellow curves) between the response measurements and 

both input measurements were generally near 1 across the measurement bandwidth, with the 

exception of a few frequencies where the coherence drops to ~0.6 near the first bending modes 

and 0.8 at some anti-resonances. 
31

Figure 29. Shaker 1 reference FRFs and coherence from SS1-15 random test 

Figure 30. Shaker 2 reference FRFs and coherence from SS1-15 random test 

Frequency - Hz

Log g/lbf

Amplitude /

Phase degPhase deg

0 10 20 25

100n

100m

10m

1m

100μ

10μ

1μ

0

1

800m

600m

400m

200m

0 10 20 25

-200

200

10050

0

-50

-200

200

100 50

0

-50

FRF(SS1.16.R,SS1.16.R-) 

FRF(SS1.1.R-,SS1.16.R-) 

FRF(SS1.4.T,SS1.16.R-) 

Multiple coherence(SS1.16.R,SS1.16.R) 

Multiple coherence(SS1.1.R-,SS1.1.R-) 

Multiple coherence(SS1.4.T,SS1.4.T) 

Frequency - Hz

Log g/lbf

Amplitude /

Phase degPhase deg

0 10 20 25

100n

100m

10m

1m

100μ

10μ

1μ

0

1

800m

600m

400m

200m

0 10 20 25

-200

200

10050

0

-50

-200

200

100 50

0

-50

FRF(SS1.18.R,SS1.18.R-) 

FRF(SS1.4.R-,SS1.18.R-) 

FRF(SS1.1.T,SS1.18.R-) 

Multiple coherence(SS1.18.R,SS1.18.R) 

Multiple coherence(SS1.4.R-,SS1.4.R-) 

Multiple coherence(SS1.1.T,SS1.1.T) 
32

The result of a reciprocity check (FRF of the response acceleration at one shaker location 

compared to the input force at the other shaker location) from the 50 lb-rms random test SS1-15 

is shown in Figure 31. Differences between the two FRFs indicate possible nonlinearities in the 

8 to 22 Hz range. Due to noise issues on the impedance head accelerometers, nearby 

accelerometers located on the shaker adapter plates (see Figure 17) were used for the reciprocity 

check. Some of the differences between the FRF measurements may be due to the fact that the 

load cell and drive point accelerometers were not co-located. 

Figure 31. Reciprocity from SS1-15 random test 

In order to check that the work platform the shakers were mounted to did not have an effect on 

the input force, the autospectra of the input forces were checked for significant dips. Figure 32 

shows the autospectra for the 50 lb-rms force SS1-15 random test, which did not indicate any 

significant dips over the frequency range of interest. 

Another check on the input forces was performed using principal component analysis. Results of 

this analysis for the SS1-15 random test are shown in Figure 33. The blue and green curves are 

the principal input force spectra, and there was not more than a 10 dB drop between the two 

across the frequency band. This indicates that there is little to no correlation between the input 

force signals in the bandwidth of interest. This conclusion can also be reached by observing the 

coherence between the input forces, which was near zero across the frequency band. 

Frequency - Hz

Log g/lbf Phase deg

0 10 20 25

5n

100μ

10μ

1μ

100n

0 10 20 25

-200

200

100

50

0

-50

-100

FRF(SS1.18.R,SS1.16.R-) 

FRF(SS1.16.R,SS1.18.R-) 
33

Figure 32. Input autopower from SS1-15 random test 

Figure 33. Principal input spectra and coherence from SS1-15 random test 

Frequency - Hz

Log lbf2 pk

0 10 20 25

10m

100

10

1

100m

Autopow er(SS1.16.R-,SS1.16.R-) 

Autopow er(SS1.18.R-,SS1.18.R-) 

Frequency - Hz

dB Ref 50.5f lbf2/Hz

Amplitude /

0 10 20 25

240

340

320

300

280

260

0

1

800m

600m

400m

200m

Principal force spectrum 1 

Principal force spectrum 2 

Coherence(SS1.16.R-,SS1.18.R-) 
34

Figures 34-36 show a comparison of the random FRFs for three force levels. As shown in the 

figures, the Stack 1 subassembly has some change in the FRFs due to force level. This is 

highlighted in the zoomed areas of Figure 36. Table 5 shows the peak frequencies for the 1st

bending modes, which varied by as much as 2.3% from the 20 lb-rms to 100 lb-rms tests. The 

data indicates some nonlinearity in the structure or boundary conditions for the tested force 

levels. Because the nature of random excitation is to linearize test results, sine sweep tests were 

also performed to investigate possible nonlinearities in the test article. 

Figure 34. Radial direction FRFs from random tests SS1-6(Run 2), SS1-12, and SS1-15 

Frequency - Hz

Log g/lbf Phase deg

0 10 20 25

100n

100m

10m

1m

100μ

10μ

1μ

0 10 20 25

-200

200

10050

0

-50

FRF(SS1.1.R-,SS1.16.R-)[20lb-rms] 

FRF(SS1.1.R-,SS1.16.R-)[50lb-rms] 

FRF(SS1.1.R-,SS1.16.R-)[100lb-rms] 
35

Figure 35. Tangential direction FRFs from random tests SS1-6(Run 2), SS1-12, and SS1-15 

Figure 36. Drive point FRFs from random tests SS1-6(Run 2), SS1-12, and SS1-15 

Frequency - Hz

Log g/lbf Phase deg

0 10 20 25

100n

100m

10m

1m

100μ

10μ

1μ

0 10 20 25

-200

200

10050

0

-50

FRF(SS1.4.T,SS1.16.R-)[20lb-rms] 

FRF(SS1.4.T,SS1.16.R-)[50lb-rms] 

FRF(SS1.4.T,SS1.16.R-)[100lb-rms] 

[ 1] 16 +X : 16 -X

[ 1] 18 +X : 18 -X

[ 2] 16 +X : 16 -X

[ 2] 18 +X : 18 -X

[ 3] 16 +X : 16 -X

[ 3] 18 +X : 18 -X

0 5 10 15 20 25 30

10

- 7

10

- 6

10

- 5

10

- 4

10

- 3

10

- 2

Frequency

Log Magnitude

FRF Overlay - [1]SS1-6Run2 (20lbrms) [2]SS1-12 (100lbrms) [3]SS1-15 (50lbrms)

1.6 1.8 2 2.2

10

-3.6

10

-3.5

Zoomed View

16 17 18 19 20 21 22

10

-3.4

10

-3.3

10

-3.2

10

-3.1

Zoomed View
36

Table 5 Peak Frequency Variation for Random Excitation

Mode

Random 20 lb-rms

Peak Frequency (Hz)

Random 100 lb-rms

Peak Frequency (Hz)

Percent

Difference (%)

1 1.64 1.66 0.96

2 2.03 1.98 -2.31

4.3 Sine Sweep Data Analysis 

Sine sweep tests were performed to evaluate the linearity of the response with respect to 

excitation level. One important parameter for obtaining useful results from a sine sweep is the 

sweep rate. Sweep rates were selected based on the recommendation by Ewins [8] that the 

sweep rate must be less than 216(fn)

2

(ζn)

2

 Hz/min. Each mode was swept individually from -6% 

to 5% of the natural frequency estimated from the curve fit of the random data sets. Some 

sweeps were stopped before reaching 5% of the natural frequency if the data indicated that the 

response was less than half of the peak value. This can be seen in Figure 37, where the red curve 

was a 50 lb-pk sweep across the -6% to 5% frequency range, but the 100 lb-pk green and 150 lbpk blue curves were stopped earlier. Note that Figures 37 and 38 are the response amplitude in 

g’s versus the sweep frequency. The frequencies at the peak response for each case are listed in 

Table 6. The peaks in Figure 37 indicate that mode 2 had a 1.9% change in peak frequency for 

the three-time change in force, which is comparable to the change observed in the random tests. 

For mode 1, the peak frequency change was more significant for the sine sweeps resulting in a 

3.7% difference for the three-time change in force. The reason for the nonlinearity is likely due 

to the uncertain boundary condition for the Stack 1 test and may not be representative of 

nonlinearity in the Stack 1 structure itself. However, there is no means to separate the influence 

of the structure and boundary condition. 
37

Figure 37. Variation in mode 2 due to varying sine sweep levels (SS1-10) 

Figure 38. Variation in mode 1 due to varying sine sweep levels (SS1-11) 
38

Table 6 Peak Frequency Variation Due to Sine Sweep Excitation Level 

Mode

Sweep Up

50 lb-pk Peak

Frequency (Hz)

Sweep Up

100 lb-pk Peak

Frequency (Hz)

Sweep Up

150 lb-pk Peak

Frequency (Hz)

50 vs. 150 lb-pk

Percent

Difference (%)

1 1.6649 1.6284 1.6037 -3.68

2 2.0070 1.9850 1.9698 -1.85

4.4 Impact Data Analysis 

Impact tests were used during the Stack 1 modal test in order to investigate local modes of 

individual components and to help resolve some of the bending/shell modes with significant 

participation at the top of Stack 1. Sampling parameters were a 128 Hz sample rate, 8-second 

block size, and 5 averages. At some locations, a 256 Hz sample rate was used in order to 

identify peak responses out to 100 Hz. Chosen locations included an internal platform, the 

frustum, the FSAM mounting location, and the FTS mounting location as defined in Table 4. 

At the request of the project, sensors were added to the FSAM and FTS to evaluate local mode 

response and the potential for tuning with anticipated launch forcing frequencies. The axial 

impact response of the FSAM is shown in Figure 39. Natural frequencies at 43.1 and 91.4 Hz 

correlated well with predictions of FSAM platform modes. For the FTS, radial and axial impacts 

are shown in Figure 40. Modes to approximately 40 Hz appear to align with global modes of 

Stack 1 but the dominant frequencies between 79.3 and 104 Hz may be local modes of the FTS 

mounting plate. This data was provided to the project for further assessment. 

To aide in the resolution of the Stack 1 global modal response, several impacts were made on the 

IS-1 platform and frustum. Figure 41 shows axial impact response of the IS-1 platform, which 

indicates modal response at 16.6, 38.3 and 45.9 Hz. A global mode of Stack 1 is at 16.6 Hz but 

the modes at 38.3 and 45.9 Hz appear to be local modes of the platform in the axial direction. 

Responses from impacts at the frustum are shown in Figure 42. The dominant modal response 

indicated at 13.6 and 25.6 Hz align with shell modes of Stack 1. A comparison of sample FRFs 

from the random shaker (Test: SS1-9) and impact tests is provided in Figures 43 and 44. Based 

on this response comparison, it is evident that the shakers are not positioned well for exciting 

some of the shell/bending modes that have significant participation at the Interstage level. 

Therefore, some further clarification of modes may be possible through detailed analysis of the 

frustum impact data. 
39

Figure 39. FRF and coherence from impacts at FSAM in –X direction 

Figure 40. FRF and coherence from impacts at FTS in –R and –X directions 

Frequency - Hz

Log g/lbf

Amplitude /

Phase degPhase deg

0 20 40 60 80 100

1μ

100m

10m

1m

100μ

10μ

0

1

800m

600m

400m

200m

0 20 40 60 80 100

-200

200

100

50

0

-50

-100

-200

200

100

50

0

-50

-100

FRF(SS1.46.X,SS1.53.X-) 

FRF(SS1.47.X,SS1.53.X-) 

Coherence(SS1.46.X,SS1.53.X-) 

Coherence(SS1.47.X,SS1.53.X-) 

Frequency - Hz

Log g/lbf

Amplitude /

Phase degPhase deg

0 50 100 130

1μ

100m

10m

1m

100μ

10μ

0

1

800m

600m

400m

200m

0 50 100 130

-200

200

100

50

0

-50

-100

-200

200

100

50

0

-50

-100

FRF(SS1.49.R-,SS1.54.R) 

FRF(SS1.49.X-,SS1.54.X) 

Coherence(SS1.49.R-,SS1.54.R) 

Coherence(SS1.49.X-,SS1.54.X) 
40

Figure 41. FRF from impacts at IS-1 platform in X direction and response locations 39-41 

Figure 42. FRF from impacts at frustum 

Frequency - Hz

Log g/lbf Phase deg

0 10 20 30 40 50

1μ

10m

1m

100μ

10μ

0 10 20 30 40 50

-200

200

100

50

0

-50

-100

FRF(SS1.39.X-,SS1.52.X) 

FRF(SS1.40.X-,SS1.52.X) 

FRF(SS1.41.X-,SS1.52.X) 

Frequency - Hz

Log g/lbf

Amplitude /

Phase degPhase deg

0 10 20 30 40 50

1μ

1m

100μ

10μ

0

1

800m

600m

400m

200m

0 10 20 30 40 50

-200

200

100

50

0

-50

-100

-200

200

100

50

0

-50

-100

FRF(SS1.3.R-,SS1.50.R-) 

FRF(SS1.8.R-,SS1.57.R) 

Coherence(SS1.3.R-,SS1.50.R-) 

Coherence(SS1.8.R-,SS1.57.R) 
41

Figure 43. Comparison of FRF and coherence from impact at frustum (51R-) and multiinput random shaker test (16R-, 18R-) 

Figure 44. Comparison of FRF from impact at frustum (50R-) and multi-input random 

shaker test (16R-, 18R-) 

Frequency - Hz

Log g/lbf

Amplitude /

Phase degPhase deg

0 10 20 30 40 50

10n

10m

1m

100μ

10μ

1μ

100n

0

1

800m

600m

400m

200m

0 10 20 30 40 50

-200

200

100

50

0

-50

-100

-200

200

100

50

0

-50

-100

FRF(SS1.1.R-,SS1.51.R-) 

FRF(SS1.1.R-,SS1.16.R-) 

FRF(SS1.1.R-,SS1.18.R-) 

Coherence(SS1.1.R-,SS1.51.R-) 

Multiple coherence(SS1.1.R-,SS1.1.R-) 

Frequency - Hz

Log g/lbf Phase deg

0 10 20 30 40 50

1μ

1m

100μ

10μ

0 10 20 30 40 50

-200

200

100

50

0

-50

-100

FRF(SS1.3.R-,SS1.50.R-) 

FRF(SS1.1.R-,SS1.16.R-) 

FRF(SS1.4.R-,SS1.18.R-) 
42

5.0 Experimental Modal Analysis Results 

Three independent estimates of the modal parameters [9-11] were made using the random data. 

Individuals performing the modal estimation noted several difficulties associated with 

nonlinearity and observability of the modes for Stack 1. As was discussed in Section 4, some 

nonlinearity in the FRF estimates for different excitation levels was observed. It is believed that 

the unconventional boundary condition was a significant contributor to the nonlinearity. With 

regard to observability, parameter estimation above 15 Hz was difficult due to many local modes 

exhibiting shell behavior and possibly modes of uninstrumented hardware. It was known during 

the pre-test analysis that higher order modes would need to be assessed on a qualitative basis (see 

Section 2.3). However, late updates to the FEM after instrumentation placement and a much 

more compliant boundary than assumed in the baseline model further complicated the 

observability issue. The boundary condition compliance resulted in more axial participation. 

Since this was not anticipated, the majority of the sensors were optimized for measuring radial or 

tangential motion, except for instrumentation at the boundary. 

Results for the three independent estimates are provide in Table 7 and select mode shapes are 

shown in Appendix E. The MSFC estimates [9] are primarily from the 20 lb-rms multi-input 

random test SS1-6(Run 2) with one mode from the higher level multi-input random test SS1-12 

added at mode 4. Aerospace Corporation [10] provided a reduced set of modes with frequency 

estimates from the higher excitation levels and the estimates from LaRC [11] were from a quick 

on-site assessment of the 50 lb-rms test SS1-7. The Stack 1st bending mode pair and 1st torsion 

mode were readily identified. For the higher modes, the estimates required more data 

manipulation and engineering judgment. Only the reduced set of mode estimates that were 

matched to the target modes (see Table 1 and Figure 4) were included in Table 7. If the 

measured frequencies of the 1st bending and torsion modes are compared with the pre-test 

predictions in Table 1, it is obvious that the test boundary condition is significantly more 

compliant than the pre-test model. Comparisons between test and analysis and a description of 

the model calibration process can be found in Horta [5]. 
43

Table 7 Reduced set of Modal Estimates 

Mode Frequency (Hz) and Damping (% critical ) Estimates Description

MSFC [9] Aerospace [10] LaRC [11]

1 1.64 Hz, 0.66% 1.65 Hz 1.63 Hz, 0.88% Stack 1st Bending

2 2.03 Hz, 0.47% 1.99 Hz 2.02 Hz, 0.70% Stack 1st Bending

3 11.34 Hz, 0.41% 11.31 Hz 11.3 Hz, 0.47% Torsion

4 13.67, 0.42% (SS1-12) 13.67 Hz 2N Shell mode

5 16.35, 1.98% 16.30 Hz 2

nd Bending

6 16.79 Hz, 0.66% 16.76 Hz 16.7 Hz, 0.62%

16.8 Hz, 0.44%

2N Shell mode

7 19.97 Hz, 0.19% 19.48 Hz 2

nd Bending

8 24.78 Hz, 0.34% 24.74 Hz 24.8 Hz, 0.39% 3N shell mode

9 25.56 Hz, 0.49% 25.5 Hz 25.6 Hz, 0.83% 3N shell mode

6.0 Summary 

A reduced set of test modes was determined from three independent estimates of the modal 

parameters. Based on a qualitative assessment, all target mode response behavior from Table 1 

was captured in the reduced set of test modes. However, the test modes did not exhibit the 

predicted coupled response for the 2nd bending and 3N shell modes (see modes 7-8 of Table 1). 

Pre-test analysis frequencies from Table 1 were significantly higher than the measured 

frequencies for the 1st bending mode pair and 1st torsion mode. These discrepancies are mainly 

due to the assumed boundary stiffness in the baseline model being significantly higher than the 

as tested configuration. Comparisons between the Stack 1 pre-test model and measured data as 

well as a description of the model calibration process can be found in Horta [5, 12]. Horta [5] 

incorporated the boundary effects using grounded springs in the FEM calibration process. The 

resulting optimized boundary spring values corrected a problem with the principal directions for 

the 1st bending mode pair and also reduced the frequency errors. Although high frequency 

modes were difficult to observe with the limited instrumentation suite, qualitative assessments of 

test modes with orthogonality values greater than 0.8 revealed that many of these modes 

resembled modes found in the analysis. 
44

Results from multiple levels of random and sine sweep tests indicated some nonlinearity in the 

response, which was attributed to the unconventional test boundary condition. This was 

observed in the FRFs for different random force levels (see Figure 36) and the sine sweep tests. 

During the sine sweeps, a 3.7% difference in the first mode frequency was measured for a threetime change in force. 

 Due to limited time between the Stack 1 test and the modal test on the fully integrated Flight 

Test Vehicle (FTV) on the Mobile Launcher Platform (MLP), efforts were shifted to pre-test 

preparation for the FTV on MLP configuration. Additional data analysis and model calibration 

studies could have been performed for the Stack 1 configuration if the FTV test results indicated 

the need for model updates in this area of the FEM. However, the FTV on MLP test results [2, 

5] were consistent with FEM predictions so no further analysis was performed for Stack 1. 

Due to concerns over potential local mode resonance with anticipated launch excitation 

frequencies, accelerometers were added mid-test to evaluate local mode response at the FSAM 

and FTS locations. Measured frequencies from the FSAM impact tests confirmed predictions of 

local modes for the FSAM platform. Impact data for the FTS and FTS battery locations were 

provided to project personnel to evaluate possible local mode tuning issues. 

 Lessons Learned: 

This effort reinforced the need to incorporate well-defined boundary conditions into the modal 

test. Unknown boundary conditions add test configuration dependent parameters to the FEM 

calibration process, which are not part of the final set of system parameters needed. For this 

configuration, the boundary condition was more compliant than anticipated resulting in 

complications for both the modal parameter estimation (see Section 5.0) and model calibration 

process [5]. 

One additional complicating factor for parameter estimation was the residual effects from out of 

band shell modes (>40 Hz) that dominated the drive point FRFs (see Figure 19). For future tests 

of cylindrical structures, excitation along a tangential direction should be considered as a means 

of minimizing this effect. 

References: 

[1] NASA Fact Sheet, Constellation Program: Ares I-X Flight Test Vehicle, FS-2009-03-007-

JSC, 2009. http://www.nasa.gov/pdf/354470main_aresIX_fs_may09.pdf 

[2] Buehrle, R. D., Templeton, J. D., Reaves, M. C., Horta, L. G., Bartolotta, P. A., Parks, R. A., 

Lazor, D. R., and Gaspar, J. L; Ares I-X Flight Test Vehicle: Stack 5 Modal Test, NASA/TM2010-216183, January 2010 

 [3] Buehrle, R. D., Templeton, J. D., Reaves, M. C., Horta, L. G., Bartolotta, P. A., Parks, R. 

A., Lazor, D. R., and Gaspar, J. L; Ares I-X Flight Test Vehicle Modal Test, NASA/TM-2010-

216182, January 2010 
45

[4] Tuttle, R., Lollock, J.A, and Hwung, J.S.: ―Identifying Goals for Ares I-X Modal Testing,‖ 

Proceedings of IMAC XXVIII, Jacksonville, FL., February 1-4, 2010. 

 [5] Horta, L. G., Reaves, M. C., Buehrle, R. D., Templeton, J. D., Lazor, D. R., Gaspar, J. L., 

Parks, R. A., and Bartolotta, P. A..; Finite Element Model Calibration Approach for Ares I-X, 

Proceedings of IMAC XXVIII, Jacksonville, Florida, February 1-4, 2010. 

 [6] Tuttle, R., and Lollock, J. A.; Modal Test Data Adjustment for Interface Compliance, 

Proceedings of IMAC XXVIII, Jacksonville, Florida, February 1-4, 2010. 

 [7] Kammer, D. C.; Sensor Placement for On-Orbit Modal Identification and Correlation of 

Large Space Structures, Journal of Guidance, Volume 14, No. 2, March-April 1991. 

[8] Ewins, D.J., Modal Testing: Theory, Practice and Application, 2nd Edition, Research Studies 

Press Ltd., pp. 231-234, 2000. 

[9] Lazor, D. R., and Parks, R. A.; Ares I-X Super Stack 1-Modal Parameter Estimation (MPE) 

Results, NASA MSFC presentation, August 11, 2009 

[10] Lollock, J.A, Tuttle, R., and Hwung, J.S.; Ares I-X SS1 Modal Test Post-test Review, 

Aerospace Corporation presentation, August 5, 2009 

[11] Gaspar, J.L.; Stack 1 Modal Test –Quick Look Data Analysis, NASA LaRC presentation, 

July 14, 2009 

[12] Horta, L. G., Reaves, M. C., Buehrle, R. D., Templeton, J. D., Lazor, D. R., Gaspar, J. L., 

Parks, R. A., and Bartolotta, P. A..; SS1 Post Test Assessment of Model Correlation, NASA 

presentation, August 18, 2009 
46

Appendix A: Acronyms and Abbreviations 

BNC (Bayonet Neill Concelman) coaxial cable connector 

CM Crew Module 

CS Coordinate System 

CDAS Critical Data Acquisition System 

DAS Data Acquisition System 

DFT Discrete Fourier Transform 

DOF Degree of Freedom 

FEM Finite Element Model 

FSAM First Stage Avionics Module 

FTINU Fault Tolerant Inertial Navigation Unit 

FRF Frequency Response Function 

FTS Flight Termination System 

FTV Flight Test Vehicle 

GRC Glenn Research Center 

GSE Ground Support Equipment 

HPS Hydraulic Power Supply 

Hz Hertz 

IEEE Institute of Electrical and Electronics Engineers 

IEPE Integrated Electronics Piezo Electric 

IPT’s Integrated Product Teams 

IS Interstage 

IVM Integrated Vehicle Model 

HB High Bay 

KSC Kennedy Space Center 

LaRC Langley Research Center 

LAS Launch Abort System 

lb Pound 
47

LVDT Linear Variable Displacement Transducer 

MIMO Multi-Input Multi-Output 

MLP Mobile Launcher Platform 

MSFC Marshall Space Flight Center 

pk Peak 

psi Pounds per square inch 

PV Principal Value 

rms Root Mean Square 

RRGU Redundant Rate Gyro Unit 

SA Spacecraft Adapter 

SE&I Systems Engineering & Integration 

SM Service Module 

SSAS Super-Segment Assembly Stand 

STDev Standard Deviation 

STI Scientific and Technical Information 

TBD To Be Determined 

TBR To Be Resolved 

UPS Uninterrupted Power Supply 

USS Upper Stage Simulator 

VAB Vehicle Assembly Building 

VXI VME eXtensions for Instrumentation 
48

Appendix B: Equipment List 

Table B.1. FTV Equipment List (1 of 3) 

DATA ACQUISITION SYSTEM (DAS) RACK

NAME MANUFACTURER MODEL SERIAL OWNER QTY CAL DATE CAL DUE MISC

VXI MAINFRAME AGILENT TECHNOLOGIES E8403A US38001676 LaRC 1 n/a n/a

SLOT-0 INTERFACE AGILENT TECHNOLOGIES E8491A US39007039 LaRC 1 n/a n/a VXI 0

16 CHANNEL DIGITIZER VXI TECHNOLOGY INC VT1432B US45004211 LaRC 1 6/26/2009 6/26/2011 VXI 1

16 CHANNEL DIGITIZER VXI TECHNOLOGY INC VT1432B US45004212 LaRC 1 6/26/2009 6/26/2011 VXI 2

16 CHANNEL DIGITIZER VXI TECHNOLOGY INC VT1432B US45004209 LaRC 1 6/26/2009 6/26/2011 VXI 3

16 CHANNEL DIGITIZER VXI TECHNOLOGY INC VT1432B US45004210 LaRC 1 6/26/2009 6/26/2011 VXI 4

16 CHANNEL DIGITIZER VXI TECHNOLOGY INC VT1432B US45004537 LaRC 1 1/22/2008 1/22/2010 VXI 5

16 CHANNEL DIGITIZER VXI TECHNOLOGY INC VT1432B US45004538 LaRC 1 1/22/2008 1/22/2010 VXI 6

4 CHANNEL SOURCE MODULE HEWLETT-PACKARD CO E1434A US37260104 LaRC 1 n/a n/a VXI 7

16 CHANNEL DIGITIZER WITH SOURCE VXI TECHNOLOGY INC VT1432B US45004540 LaRC 1 1/22/2008 1/22/2010 VXI 8

DIGITAL OSCILLOSCOPE TEKTRONIX TDS2014 C014678 LaRC 1 n/a n/a

ICP/VOLTAGE 8CH INPUT BOX AGILENT TECHNOLOGIES 3241A n/a LaRC 4 n/a n/a

VOLTAGE 8CH INPUT BOX HEWLETT-PACKARD CO 3240A n/a LaRC 4 n/a n/a

SIGNAL CONDITIONER (S/C) RACK

NAME MANUFACTURER MODEL SERIAL OWNER QTY CAL DATE CAL DUE MISC

ICP SIGNAL CONDITIONER PCB PIEZOTRONICS 584A 1135 LaRC 1 2/9/2009 2/9/2010 S/C 1

CAPACITIVE SIGNAL CONDITIONER PCB PIEZOTRONICS 478A16 151 LaRC 1 11/7/2008 11/7/2009 S/C 2

CAPACITIVE SIGNAL CONDITIONER PCB PIEZOTRONICS 478A16 157 MSFC 1 1/12/2009 1/12/2010 S/C 3

CAPACITIVE SIGNAL CONDITIONER PCB PIEZOTRONICS 478A16 154 MSFC 1 3/10/2009 3/10/2010 S/C 4

CAPACITIVE SIGNAL CONDITIONER PCB PIEZOTRONICS 478A16 312 MSFC 1 1/12/2009 1/12/2010 S/C 5

CAPACITIVE SIGNAL CONDITIONER PCB PIEZOTRONICS 478A16 311 MSFC 1 1/12/2009 1/12/2010 S/C 6

CAPACITIVE SIGNAL CONDITIONER PCB PIEZOTRONICS 478A16 290 MSFC 1 6/24/2009 12/24/2009 S/C 7

BANDPASS FILTER KROHN-HITE 3343 2080 LaRC 1 4/20/2009 4/20/2011 Shaker 1

BANDPASS FILTER KROHN-HITE 3343R 479 LaRC 1 3/11/2009 3/11/2011 Shaker 2

ICP INSTRUMENTATION

NAME MANUFACTURER MODEL SERIAL OWNER QTY CAL DATE CAL DUE SENS

IMPACT HAMMER PCB PIEZOTRONICS 086B20 4095 LaRC 1 4/9/2009 4/9/2010 1.08 mV/lbf

IMPEDANCE HEAD PCB PIEZOTRONICS 288M34 1785 MSFC 1 2/10/2009 2/10/2010 9.837 mV/lbf

V V V 1785 MSFC 1 2/10/2009 2/10/2010 99.0 mV/g

IMPEDANCE HEAD PCB PIEZOTRONICS 288M34 1783 MSFC 1 2/10/2009 2/10/2010 9.915 mV/lbf

V V V 1783 MSFC 1 2/10/2009 2/10/2010 100.3 mV/g
49

Table B.1. FTV Equipment List (2 of 3) 

MSFC ACCELEROMETERS

NAME MANUFACTURER MODEL SERIAL OWNER QTY CAL DATE CAL DUE 159.2Hz SENS (mV/g) DC SENS (mV/g)

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2562 MSFC 1 1/21/2009 1/21/2010 998 975

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2563 MSFC 1 1/21/2009 1/21/2010 1050 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2567 MSFC 1 1/22/2009 1/22/2010 1020 989

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2569 MSFC 1 1/21/2009 1/21/2010 1000 991

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2570 MSFC 1 1/21/2009 1/21/2010 964 980

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2571 MSFC 1 1/21/2009 1/21/2010 975 982

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2576 MSFC 1 1/21/2009 1/21/2010 991 975

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2577 MSFC 1 1/21/2009 1/21/2010 1050 989

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2578 MSFC 1 1/22/2009 1/22/2010 983 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2579 MSFC 1 1/21/2009 1/21/2010 1020 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2580 MSFC 1 1/21/2009 1/21/2010 1040 990

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2581 MSFC 1 1/21/2009 1/21/2010 1040 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2582 MSFC 1 1/21/2009 1/21/2010 1040 997

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2583 MSFC 1 1/21/2009 1/21/2010 1040 986

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2584 MSFC 1 1/22/2009 1/22/2010 1030 983

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2585 MSFC 1 1/22/2009 1/22/2010 996 992

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2586 MSFC 1 1/22/2009 1/22/2010 999 981

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2587 MSFC 1 1/21/2009 1/21/2010 1030 991

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2588 MSFC 1 1/22/2009 1/22/2010 1020 978

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2589 MSFC 1 1/21/2009 1/21/2010 979 983

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2591 MSFC 1 1/22/2009 1/22/2010 1040 990

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2592 MSFC 1 1/21/2009 1/21/2010 1040 986

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2595 MSFC 1 1/22/2009 1/22/2010 1010 995

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2596 MSFC 1 1/22/2009 1/22/2010 1040 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2597 MSFC 1 1/21/2009 1/21/2010 1040 997

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2598 MSFC 1 1/21/2009 1/21/2010 1020 1000

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2599 MSFC 1 1/21/2009 1/21/2010 974 991

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2601 MSFC 1 1/22/2009 1/22/2010 1000 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2603 MSFC 1 1/21/2009 1/21/2010 1030 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2605 MSFC 1 1/22/2009 1/22/2010 987 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2606 MSFC 1 1/22/2009 1/22/2010 1020 987

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2607 MSFC 1 1/22/2009 1/22/2010 1010 983

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2608 MSFC 1 1/22/2009 1/22/2010 1010 985

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2609 MSFC 1 1/21/2009 1/21/2010 1030 981

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2610 MSFC 1 1/22/2009 1/22/2010 1000 983

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2611 MSFC 1 1/21/2009 1/21/2010 1020 994

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2612 MSFC 1 1/21/2009 1/21/2010 1040 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2613 MSFC 1 1/21/2009 1/21/2010 1010 995

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2614 MSFC 1 1/22/2009 1/22/2010 1040 974

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2615 MSFC 1 1/22/2009 1/22/2010 1050 992

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2670 MSFC 1 1/22/2009 1/22/2010 1050 992

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2671 MSFC 1 1/22/2009 1/22/2010 1030 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2672 MSFC 1 1/21/2009 1/21/2010 991 986

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2673 MSFC 1 1/22/2009 1/22/2010 1030 985

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2675 MSFC 1 1/22/2009 1/22/2010 1030 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2676 MSFC 1 1/21/2009 1/21/2010 943 991

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 2679 MSFC 1 1/22/2009 1/22/2010 1030 981

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8138 MSFC 1 1/21/2009 1/21/2010 1010 976

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8139 MSFC 1 1/21/2009 1/21/2010 985 977

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8140 MSFC 1 1/21/2009 1/21/2010 1060 1020

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8141 MSFC 1 1/21/2009 1/21/2010 1010 977

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8142 MSFC 1 1/21/2009 1/21/2010 1020 999

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8156 MSFC 1 1/21/2009 1/21/2010 941 990

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8157 MSFC 1 1/21/2009 1/21/2010 977 999

 
50

Table B.1. FTV Equipment List (3 of 3) 

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8158 MSFC 1 1/21/2009 1/21/2010 1010 987

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8159 MSFC 1 1/21/2009 1/21/2010 1010 997

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8160 MSFC 1 1/21/2009 1/21/2010 994 983

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8161 MSFC 1 1/21/2009 1/21/2010 932 980

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8162 MSFC 1 1/21/2009 1/21/2010 941 965

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8163 MSFC 1 1/21/2009 1/21/2010 1030 981

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8164 MSFC 1 1/21/2009 1/21/2010 972 1000

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8165 MSFC 1 1/21/2009 1/21/2010 986 980

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8166 MSFC 1 1/21/2009 1/21/2010 979 992

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8167 MSFC 1 1/21/2009 1/21/2010 1040 989

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8168 MSFC 1 1/21/2009 1/21/2010 998 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8169 MSFC 1 1/21/2009 1/21/2010 1040 990

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8170 MSFC 1 1/21/2009 1/21/2010 1010 981

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8171 MSFC 1 1/21/2009 1/21/2010 975 985

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8172 MSFC 1 1/22/2009 1/22/2010 981 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8173 MSFC 1 1/21/2009 1/21/2010 961 979

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8174 MSFC 1 1/21/2009 1/21/2010 951 972

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8175 MSFC 1 1/21/2009 1/21/2010 962 999

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8176 MSFC 1 1/21/2009 1/21/2010 929 984

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8177 MSFC 1 1/21/2009 1/21/2010 961 983

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8178 MSFC 1 1/21/2009 1/21/2010 1090 981

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8179 MSFC 1 1/21/2009 1/21/2010 978 980

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8180 MSFC 1 1/21/2009 1/21/2010 992 994

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8181 MSFC 1 1/21/2009 1/21/2010 1040 988

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701M15 8182 MSFC 1 1/21/2009 1/21/2010 1000 996

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3711D1FA3G 517 MSFC 1 1/22/2009 1/22/2010 658 702

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3711D1FA3G 518 MSFC 1 1/22/2009 1/22/2010 661 694

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3711D1FA3G 519 MSFC 1 1/22/2009 1/22/2010 659 696

LAS PRE-INSTALLED ACCELEROMETERS

NAME MANUFACTURER MODEL SERIAL OWNER QTY CAL DATE CAL DUE 30Hz SENS (mV/g) DC SENS (mV/g)

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701G3FA3G 2020 LaRC 1 10/1/2008 10/1/2009 991.25 996.6

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701G3FA3G 2021 LaRC 1 9/29/2008 9/29/2009 998.74 1009.3

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701G3FA3G 2022 LaRC 1 10/1/2008 10/1/2009 998.93 995.9

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701G3FA3G 2023 LaRC 1 10/1/2008 10/1/2009 996.69 991.0

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701G3FA3G 2026 LaRC 1 9/29/2008 9/29/2009 993.12 991.0

CAPACITIVE ACCELEROMETER PCB PIEZOTRONICS 3701G3FA3G 2027 LaRC 1 9/29/2008 9/29/2009 997.99 1003.9

 
51

Appendix C: Instrumentation Setup and Channel Mapping 

Table C.1. Instrumentation Locations 

As-Installed Geometry

Location Radial (in) Theta (deg) Z-coord (in) Notes

1 108.25 30 1859.5

2 108.25 60 1858.7

3 108.25 105 1860

4 108.25 150 1859.2

5 108.25 195 1860.5

6 108.25 240 1858.2

7 108.25 300 1860

8 108.25 345 1860.5 R & T were switched in SS1-6 time data

9 108.25 30 1939.2

10 108.25 135 1938.5

11 108.25 192 1937.5

12 108.25 225 1939.3

13 108.25 348 1937.2

14 72.79 195 2137

15 72.79 225 2137

16 72.79 40 2335.9 Shaker 1 location

17 72.79 112.5 2328.3

18 72.79 140 2336.4 Shaker 2 location

19 72.79 210 2327.7

20 72.79 232.5 2328.1

21 72.79 300 2327.7

22 72.79 330 2327.2

23 72.79 45 2601.6

24 72.79 135 2601.6

25 72.79 225 2601.6

26 72.79 315 2601.6

27 72.79 45 2592.5

28 72.79 135 2592.5

29 72.79 225 2592.6

30 72.79 315 2592.4

31 72.79 47 2602.9

32 72.79 133 2602.9

33 72.79 228 2602.9

34 72.79 313 2602.9

35 72.79 0 2602.9

36 72.79 90 2602.9

37 72.79 180 2602.9

38 72.79 270 2602.9

39 0 0 1971 Center of IS-1 Platform

40 54 315 1971 IS-1 Platform: 54.0" from Center

41 54.6 45 1971 IS-1 Platform: 54.6" from Center

42 72.79 40 2335.9 Impedance head accelerometer at location 16

43 72.79 140 2336.4 Impedance head accelerometer at location 18

44 Unused

45 Unused

46 45 150 2480.9 FSAM-27 Inches from Center Ring. Not connected until SS1-12 test.

47 21.25 150 2480.9 FSAM-3.25 Inches from Center Ring. Not connected until SS1-12 test

48 66.79 210 2534.9 battery -radius estimated. Not connected until SS1-12 test

49 69.79 65 2569.9 FTS -radius estimated. Not connected until SS1-12 test
52

Table C.2. Instrumentation Orientations 

Location Orientation S/N Orientation S/N Orientation S/N Orientation S/N

1 -R 2589 T 2580

2 -R 2592 T 8174

3 -R 2676 T 2671

4 -R 2605 T 2606

5 -R 8159 T 8168

6 -R 2675 T 2596

7 -R 8140 T 8164

8 -R 2563 T 2615

9 -R 8139 T 8181

10 -R 2611 T 2571

11 -R 2607 T 2585

12 -R 2588 T 2595

13 -R 8177 T 2603

14 R 8169 T 8179

15 R 2583 T 2609

16 R 2614 T 2673 R- 1785

17 R 2578 T 2586

18 R 8161 T 8176 R- 1783

19 R 2610 T 2608

20 R 8157 T 2582

21 R 8156 T 8171

22 R 2601 T 2584

23 -X 8158 R 8141 T 8162

24 -X 2597 R 8180

25 -X 8167 R 2579 T 8138

26 -X 2591 R 2679

27 -X 8182

28 -X 8170

29 -X 2569

30 -X 2598

31 -X 2570 R 2576 T 8163

32 -X 8172 R 8173

33 -X 2562 R 8142 T 8160

34 -X 2587 R 8165

35 -X 8166

36 -X 2577

37 -X 8178

38 -X 2599

39 -X 2670 R 2613 T 2672

40 -X 2581 T 2612

41 -X 8175

42 R 1785

43 R 1783

44

45

46 X 3021 -R 2028 T 2029

47 X 3051 -R 3025 T 3022

48 -X 518 -R 519

49 -X 2096 -R 2095

X-Axis Accel Radial (R) Accel Tangential (T) Accel Load Cell
53

Table C.3. Transducer Channel Setup (1 of 2) 

TRANSDUCER CHANNELS

Channel Usage Name EU Sensitivity Cal Type Input ModeModel Serial

1 Excitation SS1.16.R- lbf 9.837 mV/EU Voltage 288M34 1785

2 Excitation SS1.18.R- lbf 9.915 mV/EU Voltage 288M34 1783

3 Response SS1.16.R g 974 mV/EU Voltage 3701M15 2614

4 Response SS1.18.R g 980 mV/EU Voltage 3701M15 8161

5 Response SS1.1.R- g 983 mV/EU Voltage 3701M15 2589

6 Response SS1.1.T g 990 mV/EU Voltage 3701M15 2580

7 Response SS1.2.R- g 986 mV/EU Voltage 3701M15 2592

8 Response SS1.2.T g 972 mV/EU Voltage 3701M15 8174

9 Response SS1.3.R- g 991 mV/EU Voltage 3701M15 2676

10 Response SS1.3.T g 984 mV/EU Voltage 3701M15 2671

11 Response SS1.4.R- g 984 mV/EU Voltage 3701M15 2605

12 Response SS1.4.T g 987 mV/EU Voltage 3701M15 2606

13 Response SS1.5.R- g 997 mV/EU Voltage 3701M15 8159

14 Response SS1.5.T g 984 mV/EU Voltage 3701M15 8168

15 Response SS1.6.R- g 988 mV/EU Voltage 3701M15 2675

16 Response SS1.6.T g 988 mV/EU Voltage 3701M15 2596

17 Response SS1.7.R- g 1020 mV/EU Voltage 3701M15 8140

18 Response SS1.7.T g 1000 mV/EU Voltage 3701M15 8164

19 Response SS1.8.T g 988 mV/EU Voltage 3701M15 2563

20 Response SS1.8.R- g 992 mV/EU Voltage 3701M15 2615

21 Response SS1.9.R- g 977 mV/EU Voltage 3701M15 8139

22 Response SS1.9.T g 988 mV/EU Voltage 3701M15 8181

23 Response SS1.10.R- g 994 mV/EU Voltage 3701M15 2611

24 Response SS1.10.T g 982 mV/EU Voltage 3701M15 2571

25 Response SS1.11.R- g 983 mV/EU Voltage 3701M15 2607

26 Response SS1.11.T g 992 mV/EU Voltage 3701M15 2585

27 Response SS1.12.R- g 978 mV/EU Voltage 3701M15 2588

28 Response SS1.12.T g 995 mV/EU Voltage 3701M15 2595

29 Response SS1.13.R- g 983 mV/EU Voltage 3701M15 8177

30 Response SS1.13.T g 984 mV/EU Voltage 3701M15 2603

31 Response SS1.14.R g 990 mV/EU Voltage 3701M15 8169

32 Response SS1.14.T g 980 mV/EU Voltage 3701M15 8179

33 Response SS1.15.R g 986 mV/EU Voltage 3701M15 2583

34 Response SS1.15.T g 981 mV/EU Voltage 3701M15 2609

35 Response SS1.16.T g 985 mV/EU Voltage 3701M15 2673

36 Response SS1.17.R g 984 mV/EU Voltage 3701M15 2578

37 Response Open g 1000 mV/EU Voltage NA NA

38 Response SS1.18.T g 984 mV/EU Voltage 3701M15 8176

39 Response SS1.19.R g 983 mV/EU Voltage 3701M15 2610

40 Response SS1.19.T g 985 mV/EU Voltage 3701M15 2608

41 Response Open g 1000 mV/EU Voltage NA NA

42 Response Open g 1000 mV/EU Voltage NA NA

43 Response Open g 1000 mV/EU Voltage NA NA

44 Response Open g 1000 mV/EU Voltage NA NA

45 Response SS1.22.R g 988 mV/EU Voltage 3701M15 2601

46 Response SS1.22.T g 983 mV/EU Voltage 3701M15 2584

47 Response SS1.23.X- g 987 mV/EU Voltage 3701M15 8158

48 Response SS1.23.R g 977 mV/EU Voltage 3701M15 8141

49 Response SS1.23.T g 965 mV/EU Voltage 3701M15 8162

50 Response SS1.24.X- g 997 mV/EU Voltage 3701M15 2597

51 Response SS1.24.R g 994 mV/EU Voltage 3701M15 8180
54

Table C.3. Transducer Channel Setup (2 of 2) 

TRANSDUCER CHANNELS

Channel Usage Name EU Sensitivity Cal Type Input ModeModel Serial

52 Response SS1.25.X- g 989 mV/EU Voltage 3701M15 8167

53 Response SS1.25.R g 984 mV/EU Voltage 3701M15 2579

54 Response SS1.25.T g 976 mV/EU Voltage 3701M15 8138

55 Response SS1.26.X- g 990 mV/EU Voltage 3701M15 2591

56 Response SS1.26.R g 981 mV/EU Voltage 3701M15 2679

57 Response SS1.27.X- g 996 mV/EU Voltage 3701M15 8182

58 Response SS1.28.X- g 981 mV/EU Voltage 3701M15 8170

59 Response SS1.29.X- g 991 mV/EU Voltage 3701M15 2569

60 Response SS1.30.X- g 1000 mV/EU Voltage 3701M15 2598

61 Response SS1.31.X- g 980 mV/EU Voltage 3701M15 2570

62 Response SS1.31.R g 975 mV/EU Voltage 3701M15 2576

63 Response SS1.31.T g 981 mV/EU Voltage 3701M15 8163

64 Response SS1.32.X- g 984 mV/EU Voltage 3701M15 8172

65 Response SS1.32.R g 979 mV/EU Voltage 3701M15 8173

66 Response SS1.33.X- g 975 mV/EU Voltage 3701M15 2562

67 Response SS1.33.R g 999 mV/EU Voltage 3701M15 8142

68 Response SS1.33.T g 983 mV/EU Voltage 3701M15 8160

69 Response SS1.34.X- g 991 mV/EU Voltage 3701M15 2587

70 Response SS1.34.R g 980 mV/EU Voltage 3701M15 8165

71 Response SS1.35.X- g 992 mV/EU Voltage 3701M15 8166

72 Response SS1.36.X- g 989 mV/EU Voltage 3701M15 2577

73 Response SS1.37.X- g 981 mV/EU Voltage 3701M15 8178

74 Response SS1.38.X- g 991 mV/EU Voltage 3701M15 2599

75 Response SS1.42.R g 99 mV/EU Voltage 288M34 1785

76 Response SS1.43.R g 100.3 mV/EU Voltage 288M34 1783

77 Response SS1.17.T g 981 mV/EU Voltage 3701M15 2586

78 Response Open g 1000 mV/EU Voltage NA NA

79 Response Open g 1000 mV/EU Voltage NA NA

80 Response Open g 1000 mV/EU Voltage NA NA

81 Response Open g 1000 mV/EU Voltage NA NA

82 Response Open g 1000 mV/EU Voltage NA NA

83 Response SS1.39.X- g 992 mV/EU Voltage 3701M15 2670

84 Response SS1.39.R g 995 mV/EU Voltage 3701M15 2613

85 Response SS1.39.T g 986 mV/EU Voltage 3701M15 2672

86 Response SS1.40.X- g 988 mV/EU Voltage 3701M15 2581

87 Response SS1.40.T g 988 mV/EU Voltage 3701M15 2612

88 Response SS1.41.X- g 999 mV/EU Voltage 3701M15 8175

89 Response SS1.20.R g 999 mV/EU Voltage 3701M15 8157

90 Response SS1.20.T g 997 mV/EU Voltage 3701M15 2582

91 Response SS1.21.R g 990 mV/EU Voltage 3701M15 8156

92 Response SS1.21.T g 985 mV/EU Voltage 3701M15 8171

93 Response SS1.46.X g 996 mV/EU Voltage 3701G3FA3G 3021

94 Response SS1.46.R- g 990 mV/EU Voltage 3701G3FA3G 2028

95 Response SS1.46.T g 998 mV/EU Voltage 3701G3FA3G 2029

96 Response SS1.47.X g 993 mV/EU Voltage 3701G3FA3G 3051

97 Response SS1.47.R- g 998 mV/EU Voltage 3701G3FA3G 3025

98 Response SS1.47.T g 1000 mV/EU Voltage 3701G3FA3G 3022

99 Response SS1.48.X- g 694 mV/EU Voltage 3711D1FA3G 518

100 Response SS1.48.R- g 696 mV/EU Voltage 3711D1FA3G 519

101 Response SS1.49.X- g 978 mV/EU Voltage 3701G3FA3G 2096

102 Response SS1.49.R- g 982 mV/EU Voltage 3701G3FA3G 2095
55

Table C.4. Acquisition Channel Setup (1 of 2) 

TRANSDUCER CHANNELS INPUT CHANNELS

Channel Coupling Range Offset Pre-gain Weighting

1 DC Gnd 5 V 0 1 Off

2 DC Gnd 5 V 0 1 Off

3 DC Gnd 1 V 0 1 Off

4 DC Gnd 1 V 0 1 Off

5 DC Gnd 1 V 0 1 Off

6 DC Gnd 1 V 0 1 Off

7 DC Gnd 1 V 0 1 Off

8 DC Gnd 1 V 0 1 Off

9 DC Gnd 1 V 0 1 Off

10 DC Gnd 1 V 0 1 Off

11 DC Gnd 1 V 0 1 Off

12 DC Gnd 1 V 0 1 Off

13 DC Gnd 1 V 0 1 Off

14 DC Gnd 1 V 0 1 Off

15 DC Gnd 1 V 0 1 Off

16 DC Gnd 1 V 0 1 Off

17 DC Gnd 1 V 0 1 Off

18 DC Gnd 1 V 0 1 Off

19 DC Gnd 1 V 0 1 Off

20 DC Gnd 1 V 0 1 Off

21 DC Gnd 1 V 0 1 Off

22 DC Gnd 1 V 0 1 Off

23 DC Gnd 1 V 0 1 Off

24 DC Gnd 1 V 0 1 Off

25 DC Gnd 1 V 0 1 Off

26 DC Gnd 1 V 0 1 Off

27 DC Gnd 1 V 0 1 Off

28 DC Gnd 1 V 0 1 Off

29 DC Gnd 1 V 0 1 Off

30 DC Gnd 1 V 0 1 Off

31 DC Gnd 1 V 0 1 Off

32 DC Gnd 1 V 0 1 Off

33 DC Gnd 1 V 0 1 Off

34 DC Gnd 1 V 0 1 Off

35 DC Gnd 1 V 0 1 Off

36 DC Gnd 1 V 0 1 Off

37 DC Gnd 10 V 0 1 Off

38 DC Gnd 1 V 0 1 Off

39 DC Gnd 1 V 0 1 Off

40 DC Gnd 1 V 0 1 Off

41 DC Gnd 10 V 0 1 Off

42 DC Gnd 10 V 0 1 Off

43 DC Gnd 10 V 0 1 Off

44 DC Gnd 10 V 0 1 Off

45 DC Gnd 1 V 0 1 Off

46 DC Gnd 1 V 0 1 Off

47 DC Gnd 1 V 0 1 Off

48 DC Gnd 100 mV 0 1 Off

49 DC Gnd 100 mV 0 1 Off

50 DC Gnd 100 mV 0 1 Off

51 DC Gnd 100 mV 0 1 Off
56

Table C.4. Acquisition Channel Setup (2 of 2) 

TRANSDUCER CHANNELS INPUT CHANNELS

Channel Coupling Range Offset Pre-gain Weighting

52 DC Gnd 100 mV 0 1 Off

53 DC Gnd 100 mV 0 1 Off

54 DC Gnd 100 mV 0 1 Off

55 DC Gnd 100 mV 0 1 Off

56 DC Gnd 100 mV 0 1 Off

57 DC Gnd 100 mV 0 1 Off

58 DC Gnd 100 mV 0 1 Off

59 DC Gnd 100 mV 0 1 Off

60 DC Gnd 100 mV 0 1 Off

61 DC Gnd 500 mV 0 1 Off

62 DC Gnd 100 mV 0 1 Off

63 DC Gnd 100 mV 0 1 Off

64 DC Gnd 100 mV 0 1 Off

65 DC Gnd 100 mV 0 1 Off

66 DC Gnd 100 mV 0 1 Off

67 DC Gnd 100 mV 0 1 Off

68 DC Gnd 100 mV 0 1 Off

69 DC Gnd 100 mV 0 1 Off

70 DC Gnd 100 mV 0 1 Off

71 DC Gnd 100 mV 0 1 Off

72 DC Gnd 100 mV 0 1 Off

73 DC Gnd 100 mV 0 1 Off

74 DC Gnd 1 V 0 1 Off

75 DC Gnd 500 mV 0 1 Off

76 DC Gnd 500 mV 0 1 Off

77 DC Gnd 1 V 0 1 Off

78 DC Gnd 10 V 0 1 Off

79 DC Gnd 10 V 0 1 Off

80 DC Gnd 10 V 0 1 Off

81 DC Gnd 10 V 0 1 Off

82 DC Gnd 10 V 0 1 Off

83 DC Gnd 1 V 0 1 Off

84 DC Gnd 1 V 0 1 Off

85 DC Gnd 1 V 0 1 Off

86 DC Gnd 1 V 0 1 Off

87 DC Gnd 1 V 0 1 Off

88 DC Gnd 1 V 0 1 Off

89 DC Gnd 1 V 0 1 Off

90 DC Gnd 1 V 0 1 Off

91 DC Gnd 1 V 0 1 Off

92 DC Gnd 1 V 0 1 Off

93 DC Gnd 1 V 0 1 Off

94 DC Gnd 1 V 0 1 Off

95 DC Gnd 1 V 0 1 Off

96 DC Gnd 1 V 0 1 Off

97 DC Gnd 1 V 0 1 Off

98 DC Gnd 1 V 0 1 Off

99 DC Gnd 1 V 0 1 Off

100 DC Gnd 1 V 0 1 Off

101 DC Gnd 1 V 0 1 Off

102 DC Gnd 1 V 0 1 Off
57

Table C.5. Channel Connectivity (1 of 2) 

SIGNAL CONDITIONER CHANNELS PATCH PANEL VXI CHANNELS

Channel Box Channel Type Cable Connector Box Channel Card Group

1 1 1 ICP BNC 1 1 1 1

2 1 2 ICP BNC 1 2 1 1

3 2 3 Capacitive BNC 1 3 1 1

4 2 4 Capacitive BNC 1 4 1 1

5 2 5 Capacitive Agilent 2 1 2

6 2 6 Capacitive Agilent 2 1 2

7 2 7 Capacitive Agilent 2 1 2

8 2 8 Capacitive Agilent 2 1 2

9 2 9 Capacitive Agilent 3 1 3

10 2 10 Capacitive Agilent 3 1 3

11 2 11 Capacitive Agilent 3 1 3

12 2 12 Capacitive Agilent 3 1 3

13 2 13 Capacitive Agilent 4 1 4

14 2 14 Capacitive Agilent 4 1 4

15 2 15 Capacitive Agilent 4 1 4

16 2 16 Capacitive Agilent 4 1 4

17 3 1 Capacitive Agilent 1 2 1

18 3 2 Capacitive Agilent 1 2 1

19 3 3 Capacitive Agilent 1 2 1

20 3 4 Capacitive Agilent 1 2 1

21 3 5 Capacitive Agilent 2 2 2

22 3 6 Capacitive Agilent 2 2 2

23 3 7 Capacitive Agilent 2 2 2

24 3 8 Capacitive Agilent 2 2 2

25 3 9 Capacitive Agilent 3 2 3

26 3 10 Capacitive Agilent 3 2 3

27 3 11 Capacitive Agilent 3 2 3

28 3 12 Capacitive Agilent 3 2 3

29 3 13 Capacitive Agilent 4 2 4

30 3 14 Capacitive Agilent 4 2 4

31 3 15 Capacitive Agilent 4 2 4

32 3 16 Capacitive Agilent 4 2 4

33 4 1 Capacitive Agilent 1 3 1

34 4 2 Capacitive Agilent 1 3 1

35 4 3 Capacitive Agilent 1 3 1

36 4 4 Capacitive Agilent 1 3 1

37 4 5 Capacitive Agilent 2 3 2

38 4 6 Capacitive Agilent 2 3 2

39 4 7 Capacitive Agilent 2 3 2

40 4 8 Capacitive Agilent 2 3 2

41 4 9 Capacitive Agilent 3 3 3

42 4 10 Capacitive Agilent 3 3 3

43 4 11 Capacitive Agilent 3 3 3

44 4 12 Capacitive Agilent 3 3 3

45 4 13 Capacitive Agilent 4 3 4

46 4 14 Capacitive Agilent 4 3 4

47 4 15 Capacitive Agilent 4 3 4

48 4 16 Capacitive Agilent 4 3 4

49 5 1 Capacitive Agilent 1 4 1

50 5 2 Capacitive Agilent 1 4 1

51 5 3 Capacitive Agilent 1 4 1
58

Table C.5. Channel Connectivity (2 of 2) 

SIGNAL CONDITIONER CHANNELS PATCH PANEL VXI CHANNELS

Channel Box Channel Type Cable Connector Box Channel Card Group

52 5 4 Capacitive Agilent 1 4 1

53 5 5 Capacitive BNC 3 5 4 2

54 5 6 Capacitive BNC 3 6 4 2

55 5 7 Capacitive BNC 3 7 4 2

56 5 8 Capacitive BNC 3 8 4 2

57 5 9 Capacitive Agilent 3 4 3

58 5 10 Capacitive Agilent 3 4 3

59 5 11 Capacitive Agilent 3 4 3

60 5 12 Capacitive Agilent 3 4 3

61 5 13 Capacitive Agilent 4 4 4

62 5 14 Capacitive Agilent 4 4 4

63 5 15 Capacitive Agilent 4 4 4

64 5 16 Capacitive Agilent 4 4 4

65 6 1 Capacitive Agilent 1 5 1

66 6 2 Capacitive Agilent 1 5 1

67 6 3 Capacitive Agilent 1 5 1

68 6 4 Capacitive Agilent 1 5 1

69 6 5 Capacitive Agilent 2 5 2

70 6 6 Capacitive Agilent 2 5 2

71 6 7 Capacitive Agilent 2 5 2

72 6 8 Capacitive Agilent 2 5 2

73 6 9 Capacitive BNC 1 5 5 3

74 6 10 Capacitive BNC 1 6 5 3

75 1 3 ICP BNC 1 7 5 3

76 1 4 ICP BNC 1 8 5 3

77 4 13 Capacitive BNC 2 1 5 4

78 1 6 ICP BNC 2 2 5 4

79 1 7 ICP BNC 2 3 5 4

80 1 8 ICP BNC 2 4 5 4

81 1 9 ICP BNC 2 5 6 1

82 1 10 ICP BNC 2 6 6 1

83 6 11 Capacitive BNC 2 7 6 1

84 6 12 Capacitive BNC 2 8 6 1

85 6 13 Capacitive BNC 3 1 6 2

86 6 14 Capacitive BNC 3 2 6 2

87 6 15 Capacitive BNC 3 3 6 2

88 6 16 Capacitive BNC 3 4 6 2

89 4 9 Capacitive BNC 4 1 6 3

90 4 10 Capacitive BNC 4 2 6 3

91 4 11 Capacitive BNC 4 3 6 3

92 4 12 Capacitive BNC 4 4 6 3

93 7 1 Capacitive BNC 4 5 6 4

94 7 2 Capacitive BNC 4 6 6 4

95 7 3 Capacitive BNC 4 7 6 4

96 7 4 Capacitive BNC 4 8 6 4

97 7 5 Capacitive BNC 5 1 7 1

98 7 6 Capacitive BNC 5 2 7 1

99 7 7 Capacitive BNC 5 3 7 1

100 7 8 Capacitive BNC 5 4 7 1

101 7 9 Capacitive BNC 5 5 7 2

102 7 10 Capacitive BNC 5 6 7 2
59

Appendix D: Data Acquisition Log 

Pre-Test: Integration activities were ongoing during the pre-test days so the data will be 

influenced by personnel activities (pre-test data only meant for preliminary checkouts) 

July 10, 2009: Finished accelerometer installation; completed data acquisition system setup and 

shaker installation 

SS1-1: July 11, 2009; Ambient noise data with Paul and Ryan on IS-2 catwalk exciting vehicle, 

128 Hz sample rate, 4 second block, 16 averages; Channels 21R and 21T had no signal; replaced 

high density connector with BNC’s; location 20 accelerometers at angle—corrected 7/13/09 

SS1-2: July 11, 2009; Burst random (~20 lb-rms), 50% of window, 128 Hz sample rate, .03125 

Hz resolution, 20 averages; Some work going on in FSAM area; Channel 17 T suspect; Channels 

8R and 8T have orientation swapped (corrected for 7/13/09 datasets) 

SS1-3: July 11, 2009; Burst random (~20 lb-rms), 50% of window, 128 Hz sample rate, .03125 

Hz resolution, 20 averages; Some work going on in FSAM area; Channel 17 T switched from 

channel 37 to channel 77 due to possible bad signal conditioner or VXI channel. 

SS1-4: July 11, 2009; Random (~20 lb-rms), 128 Hz sample rate, .03125 Hz resolution, 20 

averages; Some work going on in FSAM area; Need to check overlap processing as it was not 

functional for this test 

SS1-5: July 11, 2009; Impact, 128 Hz sample rate, .125 Hz resolution, 5 averages; Some work 

going on in FSAM area; Rusty and Todd in IS-1 for impact at 41X (Run 1) and 2R (Run 2); 

Stepped off platform for 41X impact to minimize influence on IS-1 platform modes 

July 12, 2009 Data review: confirmed need to swap 8R and 8T (also confirmed with visual 

inspection 7/13/09); Drive point has high response due to residual effects of shell modes >40 Hz; 

Preliminary mode frequencies significantly lower than predictions (attributed to unknown 

boundary conditions) 

Test Days 

SS1-6: July 13, 2009; Random (~23 lb-rms), 64 Hz sample rate, .015625 Hz resolution, 16 

blocks, 31 averages with hanning window and 50% overlap; lower frequency range used to try 

and reduce influence of shell modes (>40 Hz); 8R and 8T not corrected for time record—

corrected for FRF export; corrected labels for Run 2; Run 2 same parameters except resolution at 

.00781 Hz (doubled acquisition time to 34 minutes) 

SS1-7: July 13, 2009; Random (~51 lb-rms), 64 Hz sample rate, .015625 Hz resolution, 16 

blocks, 31 averages with hanning window and 50% overlap; Platform vibration noted at shakers; 

No noticeable noise in IS-1 

SS1-8: July 13, 2009; Ambient, 64 Hz sample rate, .015625 Hz resolution, 16 blocks, 31 

averages with hanning window and 50% overlap; Ambient data acquired during lunch break 
60

SS1-9: July 13, 2009; Random (~40 lb-rms), Low-pass filters on force 0-40 Hz; 128 Hz sample 

rate, .015625 Hz resolution, 16 blocks, 31 averages with hanning window and 50% overlap 

SS1-10: July 13, 2009; Sine sweep 16R-; other shaker disconnected from test article; Run 1 

aborted (20 lbs-pk); Run 2-4 1.93 to 2.13 Hz at 0.02 Hz/min; Run 2 (50 lbs-pk) sweep up and 

down; Run 3 (100 lbs-pk) sweep up; Run 4 (150 lbs-pk) sweep up; visual motion at 50 lbs; 

waveform distorted (squared off at peaks) for 150 lbs 

Data acquisition computer crash; data was archived prior to failure; switched to backup computer 

SS1-11: July 13, 2009; Sine sweep 18R-; other shaker disconnected from test article; 1.56 to 1.72 

Hz at 0.03 Hz/min; Run 1 (50 lbs-pk) sweep up and down; Run 2 (100 lbs-pk) sweep up; Run 3 

(150 lbs-pk) sweep up; wave form distorted (squared off at peaks) for 150 lbs 

July 14, 2009, Data Review Observations: Rocking modes at 1.6 and 2 Hz much lower than 

pre-test predictions (~4Hz) indicating the boundary condition was less stiff than anticipated; the 

weak axis corresponding to the 1.6 Hz mode lines up with shim locations 5 and 11 which had 

gaps prior to adding upper portion of stack (Frustum, IS-1 and IS-2); Bending modes have low 

MAC and orthogonality due to limited instrumentation and more compliant boundary. Therefore, 

the mode shape comparisons will be more qualitative; Recommendations for 2nd test day: higher 

amplitude random excitation (0-25 Hz range), higher resolution random (0-50 Hz range); impact 

tests at top of segment to identify shell/bending modes; impact tests to identify local modes near 

FSAM/FTS; and sine sweeps to try and better excite modes in 15-30 Hz range. 

July 15, 2009: Per project request, additional accelerometers added on FSAM, FTS, and FTS 

battery locations (see Table 2 locations 46-49) to better define local mode response 

SS1-12: July 15, 2009; Random (~95 lb-rms), 64 Hz sample rate, .0078125 Hz resolution, 15 

averages with hanning window and 50% overlap; 42R impedance accelerometer had intermittent 

overloads; Accelerometers 48 X and R are MEMS accelerometers and appear more noisy than 

other channels 

SS1-13: July 15, 2009; Ambient; 256 Hz sample rate, .0078125 Hz resolution, 13 averages with 

hanning window and 50% overlap; 

SS1-14: July 15, 2009; Random (~45-50 lb-rms), 256 Hz sample rate, .0078125 Hz resolution, 

25 averages with hanning window and 50% overlap; 

SS1-15: July 15, 2009; Random (~50 lb-rms), 64 Hz sample rate, .0078125 Hz resolution, 31 

averages with hanning window and 50% overlap; 

SS1-16: July 15, 2009; Impact, 5 averages; 3% Pre-trigger; 10% force window and uniform 

response window; Run 1: (50R-) 90 degree location at top of Frustum from outside, 0.125 Hz 

resolution, 128 Hz sample rate; Run 2: (51R-) 270 degree at top of Frustum from outside, 0.125 

Hz resolution, 128 Hz sample rate; For runs 3-5 two people were inside on ladders but not 

supported by the IS-1 platform; Run 3: (52X-) IS-1 platform on outer edge of platform along Ibeam at 225 degrees, 0.125 Hz resolution, 128 Hz sample rate; Run 4: (52T-) IS-1 platform on I-
61

beam at 225 degrees, 0.125 Hz resolution, 128 Hz sample rate; Run 5 (52R-) radial on closeout 

beam for IS-1 platform at 270 degree orientation, 0.125 Hz resolution, 128 Hz sample rate; Run 

6 (53X-) from inside on FSAM base plate at 120 degrees, 0.125 Hz resolution, 256 Hz sample 

rate; Run 7 (54R) from inside below FTS on stiffening ring radial at 65 degrees, 0.125 Hz 

resolution, 256 Hz sample rate; Run 8 (54X) from inside on top ring frame about 10‖ above FTS, 

0.125 Hz resolution, 256 Hz sample rate; Run 9 (55R-) from outside 122‖ up from shims at ~ 

FSAM elevation and 150 degree angle, 0.125 Hz resolution, 256 Hz sample rate; Run 10 (56R-) 

from outside 84‖ up from shims at ~FTS location and 65 degrees, 0.125 Hz resolution, 256 Hz 

sample rate; Run 11 (57R) Top of frustum at 0 degrees from inside (two people inside) ,128 Hz 

sample rate, 0.125 Hz resolution; 

SS1-17: July 15, 2009; Sine sweep 16R-; other shaker disconnected from test article; 15 to 30 Hz 

at 0.75 Hz/min; Run 1 (50 lbs-pk); one person stepped on shaker platform when sweep at ~17 

Hz, two people on platform at ~21 Hz; Run 2 (20 lbs-pk) 

NOTES OF INTEREST: 

1. SS1-1 & SS1-2: open channel for DOF 17T 

2. SS1-1 to SS1-5: 8R & 8T DOFS switched 

3. SS1-1 to SS1-5: DOF 32R actually measuring DOF 28R 

4. SS1-1 to SS1-5: People were working inside the test article during data acquisition 

5. All Test Data: Data for open channels was acquired due to software requirements. This data is 

labeled as "Open" with a direction of 0 

6. All Test Data: Data for DOFs 30X and 31X has a DC bias that could not be fully compensated 

for at the signal conditioner 

7. SS1-6: 8R & 8T DOFS switched in time data only 

8. All Test Data: 42R and 43R are impedance head accelerometers 

9. Accelerometers were added to the FSAM (46 & 47), FTS battery (48), and CRD plate (49) for 

datasets after SS1-12 
62

Appendix E: Test Mode Shapes 

Figure E.1. Stack 1st Bending at 1.64 Hz. 
63

Figure E.2. Stack 1st Bending at 2.03 Hz 
64

Figure E.3. Stack Torsion at 11.3 Hz 
65

Figure E.4. Stack 2nd Bending at 16.35 Hz 
66

Figure E.5. 2N Shell mode at 16.8 Hz 
67

Figure E.6. Stack 2nd Bending at 19.97 Hz 
68

Figure E.7. 3N Shell mode at 24.8 Hz 
69

Figure E.8. 3N Shell mode at 25.6 Hz 

 

 
REPORT DOCUMENTATION PAGE Form Approved

OMB No. 0704-0188

2. REPORT TYPE 

Technical Memorandum

 4. TITLE AND SUBTITLE

Ares I-X Flight Test Vehicle: Stack 1 Modal Test

5a. CONTRACT NUMBER

 6. AUTHOR(S)

Buehrle, Ralph D.; Templeton, Justin D.; Reaves, Mercedes C.; Horta, 

Lucas G.; Gaspar, James L.; Bartolotta, Paul A.; Parks, Russel A.; Lazor, 

Daniel R.

 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-19840

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NASA

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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

Ares I-X was the first flight test vehicle used in the development of NASA’s Ares I crew launch vehicle. The Ares I-X used a 

4-segment reusable solid rocket booster from the Space Shuttle heritage with mass simulators for the 5th segment, upper stage, 

crew module and launch abort system. Three modal tests were defined to verify the dynamic finite element model of the Ares 

I-X flight test vehicle. Test configurations included two partial stacks and the full Ares I-X flight test vehicle on the Mobile 

Launcher Platform. This report focuses on the second modal test that was performed on the middle section of the vehicle 

referred to as Stack 1, which consisted of the subassembly from the 5th segment simulator through the interstage. This report 

describes the test requirements, constraints, pre-test analysis, test operations and data analysis for the Ares I-X Stack 1 modal 

test. 

15. SUBJECT TERMS

Boundary condition; Modal parameters; Modal test; Model calibration

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(443) 757-5802

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136905.10.10.20.20

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01- 03 - 2010