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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

D.~. Introduction / Background One important aspect of creating an ergonomic workstation in transit buses is choosing an appropriate seat. The most ideal seat would be one that adjusts to all the ranges needed in the workstation design, attenuate as much vibration as possible, and is comfortable for the operator. There are several methods to measure vibration exposure to a seated person, and thus indicate what seat is the "best", some of which are described in (Gilmore, 1995~. Further, the following methods will be used to determine which seat is acceptable for the workstation prototype and guidelines, all taken from (Griffin, 19901. There are two approaches, time domain analysis and frequency analysis. In time analysis, one of the most common measures used is the root-mean-square (r.m.s.) value: R M S = [N ia2'(i)] where N is the total number of data points and aw is the weighted acceleration value. The r.m.s. value is an average measure of the peak values, and therefore is not subject to one or two extreme values. However, in motions where shocks occur, the r.m.s. value may not be an appropriate measure. To quantify this, some definitions are necessary. The peak value is defined as the maximum deviation from the r.m.s. value in a time series. Also, the crest factor is the ratio of the peak value over the r.m.s. acceleration. If the crest factor is greater than six, then the r.m.s. value is not a good representation of the vibration D-]

levels. Therefore, another measure, the root-mean-quad (r.m.q.), accounts for more of the higher acceleration levels and is a better method for high crest factor motions. RMQ=[NiaiV(i)] Further, a method that measures the cumulative exposure of vibration is through the vibration dose value (V.D.V.) which is defined as: V D V = [N ~ a4,~i)1 where Ts is the duration of the motion being analyzed. Finally, the last time analysis method used will be the seat effective amplitude transmissibility (SEAT, pronounced 'see-at') value, which is a ratio of the VDV of the seat over the VDV of the floor. The SEAT value gives another indication of what vibration is passed from floor to human. A value of 1 00% indicates similar comfort to sitting on the floor, and values less than 1 00% indicate an improvement over the floor. in the frequency domain approach, the methods used will be the power spectral density (PSD) and the transfer function or transmissibility. The PSD indicates the dominant frequencies of the r.m.s. value of the data, and the transfer function reveals how much acceleration is being passed on and at what frequencies. The seated human has natural frequencies around 4 Hz and ~ Hz (Griffin, 1990), and the bus has natural frequencies at 1-2 Hz and 10-12 Hz (Boileau and Boutlin, 19901. Therefore, it is important to investigate how the seats attenuate the vibration at the critical frequencies. D-2

D.2. Problem Statement The objective testing of the seats is made up of two distinct phases. Phase ~ includes the static evaluation of the seats. This includes evaluating the seat features (armrests, height adjust, etc.), and experimentally finding various seat parameters (i.e. cushion stiffness, suspension damping, etc.~. Phase I] involves the dynamic testing in a bus on the PTT test tracks. The goal of the dynamic testing of the transit bus seats is to relatively compare the ability of the seats to attenuate vibration. From this comparison, the seat that best isolates the vibration to the bus operator will be used in the bus operator workstation prototype. There are several different factors which effect how these seats operate during a typical transit route, and the test should be devised to accurately account for all of these variables. In this experiment, the same bus will be used for all of the trials since this will provide a control for the experiment. This bus is the Chevy bus used in previous studies by PT] (Figure D-.. (Note: Unless otherwise noted, all figures are located in Sub- appendix Dl). Also, a human ride simulator will be used as a control for human physiology (Wambold, 19861. This simulator represents a 50th percentile male and a good correlation with actual human subjects, yet is not susceptible to psychological influences such as personal mood. The two natural frequencies of the simulator are 4.25 Hz and 7.5 Hz. D-3

D.3. Equipment 50 Ib. weights P.T.T. Chevy Bus B.S.T. portable 486-66 Mhz computer with Labview software Dytran amplifier board, capability of up to six channels 5 Dytran 3 ~ 27A accelerometers and cables Seven seats from various manufacturers Air tank capable of at least ~ 00 psi Ride quality simulator Durability and economy tracks at the P.T.~. Bus Testing Facility D.4. Procedure In the Phase ~ testing, various seat parameters and general features of the seats are measured. The seat parameters include suspension mass, suspension damping ratio, cushion stiffness, and cushion mass. (The 'suspension' is defined as the part of the seat from the seat riser to the bottom of the cushion.) Natural frequency and stiffness of the seat suspension can be found using the data from Phase I! (See Section D.5.) In order to find cushion stiffness, a simple experiment is conducted. The cushion is removed from the seat, placed on a rigid surface, and the ride quality simulator base is placed on the seat. Fifty pound weights are placed on the base, and the displacement of the base is D-4

measured. Using linear regression, the slope of the force / displacement line is the stiffness of the cushion, assuming linearity. Next, to find suspension damping ratio, the seat is set up in its normal operating conditions (air hookup, etc.~. The ride dummy is placed on the seat, and the seat is given an initial displacement and released. One can then look at the acceleration response, calculate the maximum overshoot, and use that to calculate the damping ratio (a). Cushion mass is found by using a standard spring force scale, and suspension mass is obtained from manufacturer data. Finally, all the general construction features of each seat are observed, such as height adjust, fore-aft adjust, etc. In the Phase T! testing, the experiment must minimize the effect of outside influences on the evaluation of the seat. Consequently, each of the seats tested during this experiment must be subjected to the same conditions (road surfaces, speeds, driver position, etch. There are seven seats for the testing, numbered I-7 (Table D4.] below). At this time, this table should not and will not be released to any seat manufacturers or anyone who isn't affiliated with this project. However, the project investigators do intend to publish these results at a later date. Figure D-.2 - D-~.8 include photographs and general kinematic schematics of each seat and suspension linkage. Note that all seats are standard air suspension systems, except Seat #2, which is an active control air suspension (continuously varies air pressure to pneumatic spring) , and Seat #5, which is a height adjustable rigid support system. D-S

Table D4. I: Key for Seat Numbering TABLE INTENTIONALLY REMOVED. For each experimental trial, the seat is placed on an aluminum mount with a universal bolt configuration for all seven seats at the center of gravity of the Chevy bus. (See Figure D-.9 for schematics of the mount). It was found that the natural frequency of a 40 ft New Flyer bus chassis was very close to the natural frequency of the Chevy chassis (Belfiore, ~ 992~. Therefore, accelerations passed to the seat base at the center of gravity of the Chevy bus are similar to that of a 40 foot transit bus. As illustrated in Figure D- ~ . ~ 0, a total of five accelerometers are utilized, two for the seat and three for the ride simulator. One accelerometer (#!~ is placed on the top surface of the mount near the base of the seat. Another accelerometer (#2) is placed on the rigid support underneath the seat pan cushion and as close as possible to the location where the operator would sit as recommended in ISO 2361. The other accelerometers are placed on the two masses suspended in the human ride simulator (#4 on lower mass, #5 on upper mass) and on the rigid frame of the simulator near the molded base (#3~. Figure DO .l ~ shows a photo of D-6

the ride quality simulator in a seat. Also, for those seats which have an adjustable stiffness in the air spring, the seat will be adjusted to a midride setting. This will be midway between the minimum and maximum heights when the air in the spring (spring stiffness) is varied. Finally, all seats will be placed at an air pressure of ~ 00 psi, which is in the operating range for all the seats. The T/4 mile durability track at P.T.~. is used for the rough road surface simulation, and the ~ mile fuel economy track is used for the smooth road simulation. A trial on the durability track consists of one lap counterclockwise around the track (Lane ~ and Lane 6, elements ~ through 14) at the normal posted speeds (See Figure D-~.12 - D- ~ . ~ 8 for durability track elements and speeds), all starting at a common point, marked in Figure D- ~ . ~ 2. On the economy track, a trial consists of one lap counterclockwise around the track at thirty-five mph, all starting from a common point (Figure D-~.191. The testing consists of three trials on the durability track and three trials on the economy track. Each of the seven seats are tested with the ride quality simulator on each seat for all trials. To help insure repeatability in the experiment, the same person drives the bus for all trials. Further, the seats are tested in as small a time frame as possible in order to eliminate the effect of temperature variability on the road surface and to a certain extent, tire pressure. After the data is collected, it is run through two filters. The first filter is a low pass Chebychev Type ~ filter at 30 Hz to filter out the high frequency data. Because of the human resonances at 4.25 Hz and 7.5 Hz, only frequencies up to 20 Hz are important for this study. The second filter is a frequency weighting filter as presented in ISO 263 I. D-7

From the resulting acceleration data, several methods of analysis are used, including both time series and frequency domain approaches. The time series approach will include measures of r.m.s., peak value, crest factor, r.m.q., vibration dose value (VDV) , and SEAT%. For frequency domain analysis, transmissibilities for the accelerometer locations relative to the floor and power spectral densities of each accelerometer location are investigated. This allows a comparison of the seats to determine what seat isolates the most vibration from the body at the various locations and at the frequencies 4.25 Hz and 7.5 Hz, indicating the "best" seat to use in the bus operator workstation prototype. The following table (Table D4.~) summarizes the procedure for the experiment, with a listing of accelerometer locations on which each method will be applied. D-8

Table D4.2: Summary of Data Analysis Seat Model: Trial: (1, 2, 3) Durability Track Economy Track Measurements l (Accel. Channel (Accel. Channel l l Application) I Application) 1~1~ - acre! vs Lime 1; 2; 3; 4; 5 1; 2; 3; 4; 5 RMS 1 1;2;3;4;5 1 1;2,3;4;5 i Peak Value 1 1;2;3;4;5 1 1;2;3;4;5 Cmsr ~r I: 2 ·: 4: ~1; 2; 3; 4; 5 j RMQ 1 1;2;3;4;5 1 1;2;3;4;5 i VDV 1 1;2;3;4;5 1 1;2;3;4;5 S~19o I,' 1~3 PSD* ~1 1; 2; 3; 4; 5 1 1; 2; 3; 4; 5 Transfer Function* l 1,2; 1,3; 1,4; 1,5 | 1,2; 1,3; 1,4; 1,5 * For the durability track' the frequency analysis procedures can only be applied to one specific element of the track at a time. See Section D.5. l D-9

D.5. Results / Discussion The results from Phase T are shown below in Table D5.l. Various features such as tore-aft adjustment, seatbelts, armrests, etc. are listed, as well as seat parameters such as cushion stiffness, suspension damping, etc. Note that these criteria are important, but doesn't automatically rule out a certain seat, because the potential exists for retrofitting a seat to meet the required adjustment (i.e. fore-aft adjust, etc.). Table D5.1: Seat Comparison T 1 T 2 ~ Seat 3 1 4 y y N - - N N Auto 1~.3 ~ 1 7 C Feature 5 1 6 N y Lap y 3 y - 9.52 11.4 36.29 7 - N Lap y Armrest | Headrest Adjustable r Seatbelt Seat Back Tilt Lumbar Air Chambers _ Seat Back Side Air Chamber Pan Side Air Chamber _ Height Adjust (cm) _ Fore-Aft Adjust (cm) _ N y Lap y 2 y N 12.4 24.i 38.56 1.59 37.1 0.741 8.48 _ 2.36 _ 7 N - Lap - y - Lap - N y N y N N 2 1 2 2* y N , _ l _ | N _ 12.7 24.0 40.82 N N 6.99 15.2 38.10 9.21 30.3 38.56 8.32 13.~ Suspension Mass (kg) _ Number of Shocks _ Cushion Mass (kg) _ _ Cushion Stiffness (kN/m) _ Susp.Damping Ratio (if) _ Suspension Stiffness (kN/m) Natural Frequency (Hz) 1 2 1 1 1 3.15 20.9 0.440 3.18 .49 8.9 2 1.80 20.1 0.434 7.37 _ 2.20 8.9 1.36 ~ . ~ {. 1 0.59: 0.89 2.60 _ 5.1 _ 3.15 3.15 19.6 2.27 18.0 ~1 8.38 2.36 11.4 _ 30.4 _ _ 0.50: _ _ 8.60 _ _ 2.62 8.9 Cushion Thickness (cm) * Non-air lumbar chambers D-10 8.9

Table D5. I: Seat Comparison (cont.) Seat | Cushion Bottom l 1 No rigid bottom, steel plate on seat suspension 2 No rigid bottom, steel plate on seat suspension 3 No rigid bottom, steel plate on seat suspension 4 Metal plate Steel skeleton around edge 3 belts along bottom Steel skeleton around edge 3 belts along bottom l Plywood Misc. - Electronically controlled Pan can extend forward Extra 5.08 cm of fore-aft when at full height Pneumatic control of fore-aft lever Height adjusts from weight Pan rear & fore raise/lower Pan fore raise (~2.54 cm) Rigid Suspension Pan fore raise (~2.54 cm) For Phase TI of the testing, several methods were used, as stated above. The time analysis methods include rms, rmq, vdv, and SEAT values. Figure D-.20 - D-.24 show line graphs of the values obtained for each seat trial per location (floor, frame, etc.) for the I" random chuck holes element (Figure D-. of the durability track. Since each element is designed to invoke a specific response, using the entire durability track trial is not appropriate. The chuck holes element was used because it most closely simulates rough road conditions and results in nearly vertical motion of the seat and ride simulator. The other elements invoke more roll and pitch motion in the system, which complicates the results. Next, the economy track line graph results are shown in Figure D-~.25 - D- ~ .29. These two sets of data show at a certain location, such as dummy frame (essentially the vibration felt by the seated person), what acceleration levels are present for each seat. Dot!

Further, the rms results could be extrapolatec! to use with TSO 2631 to investigate how long a person shouIct be exposed to acceleration at that particular level. For example, with a vibration level of 0.2 g's (~.96 m/s2), the person's exposure time should be no more than approximately 30 min. In contrast, for accelerations of 0.05 g's (049 m/s2), the exposure time rises to between 7-8 furs. Another time domain method used was the SEAT value. These results are summarized in Figure D5. la,b below, with the seats rankest in order of increasing SEAT. Values of ~ 00% indicate no improvement in vibration comfort over sitting directly on the floor, and lesser values show an increase in vibration comfort (Iower values indicate more improvement). Also, the underlining indicates what values are not significantly different, as found by conducting a two-sided t-test (Lipson and Sheth, 1 9734. D-12

110.00 1 00.00 90.00 80.00 70.00 60.00 50.00 40.00 30.00 20.00 10.00 0.00 92.046 80.485 70.596 64.120 54.592 42.330 _ 84.914 2 7 1 6 3 Seat Figure D5. ~ a: SEAT % for I" Random Chuck Holes (Durability Track) 1 00.00 90.00 80.00 70.00 .` 50.00 A) 60.00 40.00 30.00 20.00 10.00 0.00 88.638 44.343 48.364 52.669 81.297 66.117 _ 58.591 ~ 6 4 Seat Figure D5. I b: SEAT % for Economy Track D-13

The other analysis methods deal with examining the ciata in the frequency domain. These are the PSD and transfer function or transmissibility of a data set. The PSD was found for each accelerometer location for each seat trial and averaged, giving five PSD graphs per seat per track. In addition, the transmissibilities were found for each of the accelerometer locations relative to the floor for each seat trial. Figure D-.30 - D-.43 show the PSD's and transmissibilities of the suspension and of the entire seat for each seat on the durability track hi" chuck holes), while Figure D-.44 - D-.57 show the PSD's and transmissibilities for each seat on the economy track. The PSD of a ciata set is a measure of the frequency distribution of the mean square value of the data, or the rate of change of the mean square value with respect to frequency. From all the PSD's, one can see that the dominant frequency in a bus is around 10 Hz, which is also stated by (Boileau and Boutlin, ~ 990~. Also, the transmissibility of the seat suspension relative to the floor indicates the natural frequency of the seat. These values are shown in Table D5.~. Further, the stiffness of the suspension can be found by using the equation: k =~2, m where CO,~ iS the natural frequency (rad/s), k is the stiffness (N/m), and m is the mass (kg). The suspension stiffness values are also listed in Table D5.1. Also, the transmissibilities of the lower mass and upper mass relative to the floor were found for both the durability and economy tracks. For the lower mass, the resonant frequency is known to be 4.25 Hz as stated above. For each transmissibility curve, the maximum transmissibility was found as close to 4.25 Hz as possible. Likewise, for the upper mass, the maximum transmissibility was found close to 7.5 Hz (upper mass D-14

resonance). The values were averaged together for each seat and ranked in order of increasing transmissibility. Figure D5.2a-b below show the rankings for the lower and upper masses for the durability track, and Figure D5.3a-b below show the rankings for the economy track. As before with the SEAT rankings, the underlines indicate which values are not statistically different, as found from a two-sided l-test. On the durability results, the rough road conditions lead to larger variances in the data. This results in the values being less significantly different in the statistical t-test (more underlining in the graphs). From Figure D5.l, D5.2, and D5.3, one can see that certain seats perform well in the SEAT% category, while they perform poorly in the transmissibility of lower and upper masses. For example, Seat #] ranked first or second in the SEAT, but ranked near the middle of the group for the lower mass transmissibility of the lower mass. Likewise, #3 placed in the middle of the SEAT, but placed first for the lower mass transmissibility. This indicates that Seat #! performs well over all frequency ranges, while Seat #3 does well at attenuating the vibrations which most effect the lower and upper masses. D-IS

2.0 1.5 0.5 0.0 ~_ , Figure DS.2a: Lower Mass Transm to o.e 0.6 0.4 0.2 0.0 ~1 ~/ 't 5 . Seat 1ssibilities for Durability Track 6 4 5 Seat Figure DS.2b: Upper Mass Transmissibilities for Durability Track D-16

2.5 2.0 1 .5 0.5 1.0 0.0 Figure DS.3a: 2 1.5 1 0.5 o 3 2 4 1 7 6 5 Seat Lower Mass Transmissibilities for Economy Track ,~ 3 1 2 Seat Figure DS.3b: Upper Mass Transmissibilities for Economy Track D-17

There are several reasons why there are differences in seat response. The seats can be divided up into groups according to their suspension types (Figure D-.2 - D-.. These include the passive scissor suspension with slider joints (4,6), the pin jointed suspension ~ ~ ,3,7), the rigid suspension (5), and the active scissor suspension (29. Generally, it appears that the rigid seat performed the most poorly of the seats. Next, the passive scissor suspension group was generally an improvement over the rigid seat. Finally, the pin jointed suspension group appears to perform the best of the seats, with the active scissor suspension being comparable in vibration attenuation. The reason why the passive scissor group did not do as well as the pin jointed is because the slider joints in the suspension linkage need a certain velocity to move to overcome friction (this phenomenon is called "stiction"~. Therefore, for small vibration levels, the seat suspension acts as if it were a rigid suspension. Since the pin jointed suspension has no slider joints, no stiction can occur. As stated above, Seat #3 performed better in the transmissibility categories and Seat #] performed better in the SEAT categories. This is because of differences in the most critical seat parameters: suspension stiffness, suspension damping, and cushion stiffness (Berger and Gilmore, ~ 993~. Variation of these parameters have different effects on the transmissibility curves (Gouw, 1990~. Looking at Table DS. I, Seat #3 has a larger suspension stiffness and smaller suspension damping than Seat #I. Namely, this results in a larger transmissibility curve at resonance and a lower transmissibility at frequencies above resonance. This is most likely why the SEAT is lower for Seat #l, since SEAT is a ratio of the VDV's, and VDV is a summation over the entire data set. Also, Seat #3 has a D-18

lower transmissibility around 4.25 Hz ant] 7.5 Hz than Seat #l due to the lower damping in Seat #3. Therefore, Seat #3 generally ranked higher than Seat #! in the lower mass and upper mass transmissibilities. Also, additional fine tuning of the seat is most likely a result of the differences in the seat cushion. The combination of the cushion with the suspension makes up a two degree of freedom (DOE) model. When a two DOF mode! is subjected to a forcing function, the two natural frequencies determine the response of the system at the frequency of the forcing function. For instance, the natural frequencies of the suspensions of Seat #3 and #4 are both around 2.6 Hz, while the cushion resonances occur at 8.83 Hz for Seat #3 and 7.93 Hz for Seat #4. Since Seat #4 has a cushion natural frequency that is closer to the critical frequencies of 4.25 Hz and 7.5 Hz, this indicates that the motion of the cushion may be greater for Seat #4. The transmissibilities of the two masses shown in Figure 5.6-5.7 show that indeed Seat #4 does produce a larger magnitude of vibration passed to the lower and upper masses compared to Seat #3. D.6. Conclusion All the information gained by the different methods of analysis serve to assist in deciding what seat is the "best" at isolating vibration to the driver and at the same time fulfill the requirements of the design guidelines, where height adjust and fore-aft adjust are the most important (~Icm and 25 cm, respectively). However, those seats which don't meet the adjustment requirements are by no means ruled out, because the D-19

possibility exists of retrofitting the seat if necessary. Table D6. 1 below summarizes what features are necessary for the "ideal" seat, what seats meet the requirement or are very close (i.e. one or two cm away on an adjustment), and rationales for each feature. Also, for the categories where the seats are ranked, the first place ranking is listed. if the first place position has more than one seat listed, this indicates that from the data, the seats are not significantly different, usually due to high variance in the data. Looking at Table D6.l, the most important criteria for seat selection is the lower mass and upper mass transmissibility as stated in the testing plan. (Recall that thorax / hip vibration is believed to be responsible for lower back injury.) Since the critical frequencies are 4.25 Hz and 7.5 Hz, these rankings indicate how well a seat attenuates the vibration to the two masses at these frequencies. The seat that is first in both of these categories is Seat #3. Also, Seat #3 has the necessary adjustment for height and fore-aft, and also has the proper suspension design that reduces wear and maintenance, resulting i lower costs. However, even though the SEAT value is also important, it represents a reduction of vibration over all frequencies. The transmissibilities concentrate on the resonant frequencies of the two masses, and thus is more consistent with the proposed testing plan. Therefore, Seat #3 will be used in the prototype of the bus operator workstation. However, Seat #! and #2 would be acceptable as a second and third choice for the workstation prototype. D-20

Table D6. i: The ideal Seat Feature Requirement | Seat l Fore-Aft Adjust 25 cm 1,2,3 Height Adjust 1 1 cm 1,2,3,6 Lumbar Support I air-lumbar 1 1,2,3,4,5,6 Suspension Design | Pin-joint suspension | ~1,~ Armrests adjustable 1,2,3,4 7 , SEAT % Lower is better Dur - 2,7 Transmissibility: Lower is better Dur - 3,2,1,6,7 Lower Mass Eco - 3 Transmissibility: Lower is better Dur - 3 L Upper Mass | | Eco - 3,2, 1 Rationale Guideline requirement Guideline requirement Decreases lumbar fatigue Less wear, less maintenance Guideline requirement Lower SEAT% indicates lower vibration discomfort (all frequencies) Indicates how much vibration passed to lower mass at ~4.25 Hz Indicates how much vibration passed to upper mass at ~ 7.5 Hz D-21

References Belfiore, D., 1992, "The Development and Verification of Quarter- and Half-VehicIe Models for the Dynamic Simulation of PT] Test Vehicles," M.S.M.E. Thesis' The Pennsylvania State University Berger, E. and Gilmore, B.~., 1993, "Seat Dynamic Parameters for Ride Quality," SAE 930115. Boileau, P.-E. and Boutlin, I., 1990, "Vibration Study of the Driver's Workstation in Urban Buses," TRSST report. Gilmore, B.~., 1995, "Bus Operator Work Station Evaluation and Design Guidelines Testing Plan," submitted to TCRP. - Gouw, G.J., 1990, "Increased Comfort and Safety of Drivers of Off-Highway Vehicles Using Optimal Seat Suspension," SAE 901646. Griffin, M. I., 1990, Handbook of Human Vibration, Academic Press, Inc. Lipson, C. and Sheth, N. 1973, Statistical Design and Analysis of Engineering Experiments, McGraw-Hill, Inc. Wambold, I., 1986, "Vehicle Ride Quality - Measurement and Analysis," SAE 861113 D-22

Sub-appendix D1: Figures D-23

~ A Figure D-1.1: D-24 Bus Photo .~:.: :' - ' ~

FIGURE INTENTIONALLY REMOVED. Figure D-1.2a: Seat D-25

J ~ ~ - - ~ W L4 _~ -. _ i' \ ~ Lo f /LS ~0 e1~ ~ ~2 Lo = 27.138 cm L5 = 6.985 cm L, = 3.3 15 cm 00 = 6.04 ° L2 = 33.655 cm 01 = 73.30 ° L3 = 33.497 cm 02 = 152.30 ° L4 = 37.817 cm 03 = 25.46 ° Figure D- I .2b: Seat I Suspension Linkage Dimensions D-26

FIGURE INTENTIONALLY REMOVED. Figure D-1.3a: Seat 2 D-27

- //~/ /~2 l l /2 Lo L3 = 24.13 cm Lo=24.13 cm 1 Ll = 27.57 cm - 0,= 151.07° L2 = 27.57 cm 02 = 28.93 0 ~1 \ , ~1 1 ~ f Figure D-1.3b: Seat 2 Suspension Linkage Dimensions D-28

FIGURE INTENTIONALLY REMOVED. Figure D-1.4a: Seat 3 D-29

' ~ )! ~ : ~ ~ ~ : it: ~3 Lo -A- - ~ Lo = 27.138 cm L5 = 6.985 cm Ll = 3.315 cm 00= 6.04 ° L2 = 33.655 cm 01 = 73.30 ° L3 = 33.497 cm 02= 152.30 ° L4 = 37.817 cm 03 = 25.46 ° ~1 ~L~- \~eo - -~2 Figure D-~.4b: Seat 3 Suspension Linkage Dimensions D-30

FIGURE INTENTIONALLY REMOVED. Figure D. 1 -5a: Seat 4 D-31

W:~- ~-- L3 \~\ ~ ,~ >< I ~ I I ~ I .~: ~ Lo = 9.750 cm L3 = 9.750 cm Ll = 11.194 cm 01 = 29.43 ° L2 = 1 1.194 cm 02 = 150.57 ° Figure D-l.Sb: Seat 4 Suspension Linkage Dimensions D-32

FIGURE INTENTIONALLY REMOVED. Figure D-1.6: Seat 5 D-33

FIGURE INTENTIONALLY REMOVED. Figure D- 1.7a: Seat 6 D-34

>A 1 Lo = 6.985 cm L3 = 27.918 cm L, = 27.918 cry 01 = 162.80 ° __ L2 = 6.985 cm 03 = 162.80° Figure D-~.7b: Seat 6 Suspension Linkage Dimensions D-35

FIGURE INTENTIONALLY REMOVED. Figure D-1.8a: Seat 7 D-36

r Lo r J L3 ~ . f ~3 e1 a Lo e //// ~ Lo= 18.426 cm . 00 = 43.64 ° 1 ~ Lit = 30.174 cm Hi= 127.90 ° L2 = 1 1.5 1 8 cm 03= 175.670 L3 = 42.03 cm Figure D-~.8b: Seat 7 Suspension Linkage Dimensions D-37

1.625' ~ ~ 1.563' S.25O' 1 l ~ 7.000' c S.844~ ~ _6800~. _ ~844 7 000 7. 6815' 3.12S' 4.000 ~5.375J 7.063' I ~ ¢5~.soo: L035=J 4.000: 1 ~ 2063' ,l s.Cao~ _ , i, Soot 7 ~ 00.500 ~ 3 / ' ~ ' , 2QOCO' 2300O' 5.000 ~5.125' 3.125' ha: 6.~' Note L Me hcies are syr~.e-1c oboist the vert,col centerline 10' Fror ec!ge 2 Lnless ather.~se Wed all holes ore Q5625 in d,crneter _ Figure D-1.9: Universal Seat Mount D-38

CXXXXXX E xxxxxxxx XXXXXXXX XXXXXXXX ~ XXXXXXXX ~ XXXXXXXX -E xxxxxxxx -E xxxxxxxx -E xxxxxxxx XXXXXXXX XXXXXXX X XXXXXXXX XXXXXXXX ~ X X X X X X X X T xxxxxxxx -E xxxxxxxx XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ~ Xxxxxxxx XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ~ X X X X X X X X XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXX~ XXXXXXX ~ xxxxXxxxx ~ . ) _ 3 ~ ~ .AA^~^A^~^A^^JIs^~^J~^A^~^f.~ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX~ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXxxXxxXxxxxxXxxxxxxxXXXXXXXXXXXXXXXXXXXXXxXXXXXXXXs ·.~^A^~^A^~^A^~^A^. XXXXXXXXXXXXXXXXXXXXXXXXXXX: xxxxxxxxxxx x x xr~cxxxxxxxxxxx: xxxxxxxxxxxxxx~rxxxxxxxxxxxx: xxxxXxxxxxxxxxlbcXxxxxxxxxxX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXX X X X XXX XXXXXXXXX X: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX' . XXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXX - CXXXXXXXXXXX: XXXXXXXXXXXXXX: :XXXXXXXXXXX: XXXXXXXXXXXXXX: :XXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXX: ~XX~ _ Floor 2 Under Seat Cushion 5 3 Dummy Frame 4 Lower Dummy Mass Upper Dummy Mass Figure D-~.IO: Accelerometer Locations D-39

Figure D-. I: Ride Quality Simulator in Seat D - 40

2 ~CO D ~ ~ ~ D c .= ~ 0. I_ .8 Ed -8 eB c8 t, t_e em t l,; 13 ~ ~ ~ 13 ~ ~ ~1 ""," _ ~ ,\~* .`'. i"', ~· _'~''" e · ,. e ' a._ D -41 · . : : : : ~.. ok. ; - . ., :. a. In . ~·. . - _ . :, ;^ - ._ . . as ._

- - - ~ - o t - - C o ,, . ~ . . D -42 ~ Let -1 . [ _ _! - o ._ V, so I_ . - ._ o Go a, - . . _H so ·~ Lo

- -~' I it, -r ---I In . O ~ l . - i ~ o L ~ ~ - Q by_ ~_, . 'a: MU L _~ - ~ ~ ~ I: i' D -43 U. ·3 1 - . . _. a ._

~ c! -m - lo 1 ~ C,] = ID - - 1 c - - ~D - l. en - _ 1 - .1 - ~ 3 Ld flu . ~ Cam ~ .' =- ~ _ Lit, Q U' Q _~' ( to Lo C: C ARC - 1~' - 1 = ~ . CO . - ~ it fabric -CO _ fit ~ l , , D -44 C} t J _ Cal N _ __ _ _ J ~ c r C' C' T ID · V, o o - .= Ct U' Q m of a, V] ·~ o to _. V, hi - a) · _ Lit

- I HE m me Rae Cal ~ ' 1 ~ in _ L' ' :~ -be 1 ~ _ - -~1 -A r I -~1 - ~ . ~ - -- r U. E.< OCZ C Z~3 Con - - { Cl: van D - 45 e, Cat _ o u, - C., _ ~ _ _ ~ C) i_ u - - _ o ~ - 1 an - -1 1 -~1 1 . -~-~1 - - ~1 - U, A OOZ Q- Z _ l:] Cow i: - _ C -Us oh o :' o au o He a, a, - ~3 - ~ 1 ·

J CM . _ o f 1 ~ D - 46 o ~ ~ _ _ ~ ' C) e_ C?tL - 1 o _1 ~ -1 1~ CO Z m of v 5 ·_ o rr LU in ~C~ Cl ~ ~ I=0 Cam - :- · _

= ~ ~" ~ ; 1 J 1 ~ I r ~ ,1 . % _ - o #i a= O ~ O ME - - a= o - ~- 1 ~ -47 ,_ o e

. -at - ~ OK \ i' '~ 8 = ,,, 3W" 08 J /J lo ~ 8~e" )~ rid 1~ D /A D D .. ~ ~.,~<- ~Z "D J 10 if_ c_ Red 0= o o ' ~ 1 oo an a . D - 48 so o o . . ·_

o.mo Q.~1Q .. O.~ 0.30D ohm I, 1 2 3 Seat ~ R.M.S. (~) He R.~Q he's) {FIVE Phi (1~4) Figure D-1 .20: Floor RMS, RMQ, VDV for 1" Random Chuck Hoies O Gino 0~ MOO 0-400 0.2m ONYX} t 3 ~ Sect l . ~, , 5 ~7 l _ ___ ~ R. M.Se (g s) -~ ReNteO. {9's) it V.O.Y. ~ s&~1141) Figure D-1.21: Under Cushion RMS' RMQe, VDV for 1r' Random Chuck Violas D -49

Q700 .. 0.~0 of 0.300) // _ ~ Of 0.1X o.~ / ~ ~- ~ r ~_ W. 1 2 Seat 6 7 . . . . . -A RAYS. (g.~ P.~Q tots) V.D-Y, (g-s^( l/4)) Figure D-1.22: Dummy France RMS, RMQ, VDV for 1" Randon, Chuck Holes 0-700 Of of o.4oo G.30D Gina 0~= om, /~\ : 1 ~3 4 {i Seat ~ p.~.S.~5) ' ~ H.~.O.~S) ' ~ V.O.~.-14)) _ 7 Figure D-1 .23: I ower Mass RMSt RMQ, VOV for ~ l Randon1 CtlUClt Holes D- 50

1 0.700 owe own ohms 0,~ 1 - 2 3 ~ Seat - t - I 6 7 ft.M-S. (9:~) R,~.o O'er V.D.~. (~-g^(ttO Figure D-.24: Upper Mass RMS, RMQ, VDV for 1,' Random Chuck Holes D- 51

0.3m Q. 0~200 Ott= 0.100 0,060 o.<m rid 0.300 O.=u O.t~ D.1= o.~ ~m, 1 ~3 4 Seat ~ R.~.S. (9'8) HI R. FA.~. ~ ~) - ~ Uq0.Y,~5At1~4~) . .. , ___ Figure D-1 .25: Floor films, RNIQ, VDV for Economy Track _ __ ' , _ _~ 1 1 .. ., .. . 1 _ ~ R.M~S. ~) 11 R.~.~. let's, - ~ Y.D.Y. - ~(1~) - Figure D-1 .26: Under Cushion RMS' FIldO' VDV for E=nomy Tracl~ D- 52 .

Q30t3 · 0.200 O.1 O.1= 0.000 1 2 Seat . ~ _~R.M.S. (g's) Al R.lLt.Q. ") Y... (~-s^~1 J41) ~6 7 Figure D-1.27: Dummy Frame RMSI RTY Q. YOV for Economy Tract< o.~ o.m' 0.300 o.~ O.~m o.~m t 2 S - ~5 6 Sew R.M S. {e'*) | - ~ R.MO ~ I -O-Y t~tJ~8 _ I_ Figure D-1 .28: Lower Mass RMS, RING, V0V for Economy Track D- 53

owe owe 0.1= 0.1= _ .~ I_ .- 1- 1 - 23 4 SO ... . . .. _ _~ R.~.S. (gag MAR DO. ~ ~ V.O.V. (g-~(l~t . _ Figure D-1 ale: Upper Mass R~SI R~OI VDV far Economy -crack ~ -54

Floor ~ ~0 N . ~_ 10 0 5 - 10 15 20 Under Seat Cushion ~ ~ 00 LoHrer Mass 10 l - O ~ 10 15 20 Upper Mass 10~o= ~102- 13 15 20 Frmne r - I I 10 I Cal / o 10 15 pa Fret ueng, (Hz) 0 5 10 15 20 Fraquene3r (Hz) FigureD-1.30: PSD's,Seat#l,Durability D- 55

Blow I trader Cushion (Mag) 10 - - 1ea 1C 100 50 - Q ~ i\ AS ~0k -fit It Floor ~ F=ne (Mag) 1 . ,_,, . 1 10 5 10 15 20 Floor f LInder Cushion (Ang) - _ . . 10 10 -1 O 100 , ~ \/ 1Q 15 20 Floor I Frame lAng) -TOO i 10 ,5 20 Q 5 10 15 2C F - vend (Hz) F~ tHz) Figure D-~.3I: Transmissibilities, Seat #l, Durability D- 56

Floors under Custion (Mag) - - - - ~ 10 as c' JO 100 = 50 - - as ~ -1W O ~ 4;0 .: -11;;i t Floor f Fit (Mag) 10 1 -1 _ ~5 - - 10 15 20 Floor] DInd" Cushion (Ang) __ 10 it' 10 ~ O ~ 1Q 15 20 FiCor I Frame (Ang) 100 . l , ~ -50 r~ ~ -1QO Phi . . . - ~ . . O ~ 10 'e 20 ~ ~ 10 15 TIC Frequency (Hz) Frequency (Hz) Figure D-1.32: PSD's, Seat 42, Durability D- 57

Floor I Frame (flag} :~. 0 - O Floor I Under Cushion (Mag) O 10 . ~ ,. . ~10 ~, J 10 . . . 1 10 10 ~1 100 go - G £ - ~ 50 ID ~ ,~ -t5Ot 0 5 10 li 20 0 5 10 15 20 Floor ~ Under Cushion (Ang) 0N - Floors Frame (Ang) 1.m SO . , ; ~ O ~ ~0L 1~ . - Q 6 10 15 20 0 ~ 10 15 20 Frequency (FIz) . Frequency (Hz) Figure D-1.33: Transm~ssibilities, Seat #2, Durability D - 58

FIcor be ~ oo cat JO :: 10 - 10-2 Ir I ]0 - ~ 1 1 Lower Mass .~ 10° : 0 ~ 10 15 20 0 5 10 15 20 Ursder Seat Cushion Upper Mass 1oo 0 5 10 15 20 0 F- 18 l l 5 10 iS 20 Frequency (Hz) FigureD-1.34: PSD's,Seat#3,Durability D- 59 10 10 15 Frequency (Hz)

'01 10 ~ Floor I Under Cushion (Mag) 0 - o ~ r 'l0 / / 10 o ~10 15 20 Flow ~ Under Cushion (Ang) . 50 ~\ 'mi Coot Am; ~0 loo Floor J Frame (Mag) 10 at 10-2 O ~10 15 20 50 \ ~ my' 1 . . . 1 o /\ \/ 0 5 10 15 20 Frequency {liz) ~Q -1~t -1~t - 1 - 0 5 10 15 20 Frequency (Hz) Figure D-1.35: Transmissibilities, Seat #3, Durability D - 60

Floor ~ 0 :~ 1Q - c Jo-2 N ~ I 10 - Lower Mass ~, , . . .... . / \ ~ . . . ~. . 0 5 10 15 20 0 ~10 15 20 Under Seat Cushion 10 1 0 5 1Q8 I y 10 o Ups Mass 10° 10 15 20 DITTO 1 - 10-2 I . - . . 1 0 ~ 10 15 20 fray (Hz) 10 15 20 Frequency {Hz) FigureD-~.36: PSD's,Seat#4,Durability D - 61

Floor f Under Cushion tMag) 10 - ._ ~ 10 r - ,0_tl . . ~I 0 5 10 to 20 Floor J Under Cushion (Ans) 1W 10 To 10 , Floor r Frame (Mag) I . . .. 1 \ ,/ ..1 100 - 10 15 20 0 5 Floor J Frame (Ang) 1 - 0 -Sol ~sO -100t-100 -1 ~L-1 50 ~ 10 15 20a s Frec uengy tHz) Figure D-1.37: Transmissibilities, Seat #4, Durability D - 62 - - 10 15 20 Frequency (my

Floor :L 1 0 Cat -2 10 I 1 0° Under Seat Cushion 10 10 15 20 Frarre ~ 10 r I 0 5 10 15 20 Frequency Liz) Lower Mass 10° - - tO 15 2C ~5 13 15 20 Upper Mass 10° 10 - 2 - 0 ~ 10 1S 20 Frequency Adz) Figure D-1.38: PSD's, Seat #5, Durability D - 63

t Floor I Under Cushion (Mag) - ce ~ 10° 1 Floor J FtarT e (I fag) 13 ~ . . ~10 ~ 1 11 i 10° t~ \ ., , . . , 10 10 Floor ~ Under Cushion (Ang) 1~ ~0 l . - ~ O - ~ -100 O ~10 15 20 0 5 10 15 20 .. FI=r ~ F~ (Ang) 100, __ mu -50 0 5 10 15 20 Fmquency (Hz) ~I 0 5 10 15 20 Frequency (Hz) Figure D-1.39: Transm~ssibilities, Seat #S. Durability D - 64

Floor -. 10 - c~ lop loo - ID f - - 10 15 20 Her Seat (:ushim - - - 10 . - · - 0 5 10 15 20 France loo ! tO-2, , J 10 15 20 Figure D-1.40: PSD's, Seat 46, Durability D - 65 t~ Mess 10° - - 10 15 20 Upper Mass 10 0 ~ -10 15 2G Fred (Hz)

lo. ~ - n 0 ~ 10° a, F oorl Under Cushion (Mag) - 10' 1o-l _ A.,_, - Floor J Frame (Mag) 10° 10 O ~ 10 15 20 0 ~10 15 20 Floor! Under Cushion (Ans) 100 c: - ~50t {-100 -150 100 50 -100 TO Floor ~ Frame (Ang) 1 . . , ~ 0 ~ ,0 15 ~ 0 ~ 10 15 20 Frequent (Hz) F - uen`:y tHz) Figure D-1.41: Transmissibilities, Seat X6, Durability D - 66

Floor I 10 - N Cal - '0~2t . . 1 0 5 10 15 20 Under Seat Cushion I iOO - 0 5 Ago - 10 - - 1o-2 _ 10 15 20 0 Fame - I loo - 1o-2~ 0 5 10 15 20 Frequency (Hz) FigureD-1.42: PSD's,Seat#7,Durability D - 67 Lower Mass O ~ 10 15 20 . Upper Mass 5 10 15 20 Frequer~cy (Hz)

t Floor r Under Cushion (Mag) 10 ~- ~ - ._ - D i_ 0 ~ 10 ~0 Fhor ~ Under Cushion (Ang) C \/ C -100t -150t Floor I Freme (Mag) 10° an/ ;1 10 ~: 10 1 --. ~ 0 5 10 15 200 ~10 15 20 100 50 Floor t Frame (Ang) I -I GO -150! - - ,, 0 5 10 15 20 0 5 10 15 20 F - uency (Hz) FreqwK:y (lazy Figure D-1.43: Trarlsm~ssibilities, Seat #7, Durability D - 68

Floor 0.04 5 ?, 0. 02 o T 0.02 0.01 o I 0.01 0.005 o Dummy Lower Class ~ ~~~ 0.02 0.01 n ' ~ Wt l ~ 0 5 10 15 0 5 10 15 Suspension Dummy Upper Mass I . . ~ 00O1 ~ ~ 0 ~ 10 15 0 ~10 15 Dun~my Frame _~: 0 5 10 15 Frequency (Hz) Frequency (Hz) Figure D-l .44: Seat I Average PSD Functions, Economy D - 69

1ol 10° 10 10' 10° 10-1 SuspensionfFloor ~ ' ' ' ~ ~~- / ~ 0 ~ 10 Dummy FramelFloor , . . ~ \ 0 ~ 10 15 Frequency (H~) 10' Dummy Lower hlassIFloor 10°| 10° 10-' 15 0 10' 10° . .~d : ~ 10 15 Dummy Upper MassIFloor ~\;,A~~, 1o-l 0 ~ 10 16 Frequency (H~) Figure D-] .45: Seat ~ Average Transmissibilities, Economy D - 70

0.04 By, 0. 02 o 0.01 ~ O. 005 O. 0.01 ~ 0.006 o Floor r I l o ~ 10 15 Suspension . . 1 O ~ Dummy Frame 11 · ~1 , 0.01 0.005 o 0.02 0.01 o 10 15 0 0 ~ 10 16 Frequency (Hz) Dummy Lower brass . ~ -O ~ 10 15 Dummy Upper Mass ,. . 1 . . it' ~ 10 15 Frequency (Hz) Figure D-.46: Seat 2 Average PSD Functions, Economy D - 71

10' 10° lo-l 1ol loo lo 1 SuspensionIFloor it, 1o1 10° 10-1 [: ummy Lower MassIFloor 0 ~ 10 15 0 ~10 15 Dummy FramelFloor . I . ~_\ 'O ~ Frequency (Hey 1o1 10° Dummy Upper MassIFloor 1~ ~~\ 1 10-' ~. I 10 16 0 ~ 10 Frequency (Hz) Figure D-~.47: Seat 2 Average Transm~ssibilities, Economy D- 72

Floor 0.04 O. 02 w o 0.04 0.01 I 0.005 O. Dummy Lower Mass 'O ~ 10 Suspension . . 0.02 ~ ~: ~ odor ~ 15 0 ~ 10 15 Dummy Upper Bless . . 0.04 ;4002k~;3 002~;~ 0 ~ 10 15 Dummy Frame ,~ : O ~ Frequency (Hz) O ~ 10 15 Frequency (Hz) 10 15 Figure D-~.48: Seat 3 Average PSD Functions, Economy D - 73

10 10° lo-l 10' 100 lo l SuspensionIFloor . 1 ~ · - ~ ~,:~ . . O ~ Dummy FramefFloor 10 100 10-' 10 15 0 Dummy Lower h1assIFloor it, ~ 10 15 Dummy Upper MassIFloor 1 ~ 10'1 - 1~ 10°~ 1.0 ~ 0 ~ 10 15 0 ~10 Frequency (Hz) Frequency (Hz) Figure D-1.49: Seat 3 Average Transmissibilities, Economy D - 74

Floor 0.04 at, 0. 02 ~ 0.01 0.02 0.02 ~ 0.01 . . O __ 0 ~ 10 15 Suspension 0.04 0.02 0.1 0.05 Dummy Lower Mass ,~, 10 15 Dummy Upper Class few 0 ~ 10 15 0 Dummy Frame -1 ' ' 1 ~ 10 15 Frequency (H.) ~ 10 15 Frequency (Hz) Figure D-1.50: Seat 4 Average PSD Functions Economy D- 75

1 o 1 10° 10 sol 10° 1 o -1 SuspensionIFloor 10' 10° -1 Dummy Lower h~lassIFloor ~w ~v~x 0 ~ 10 15 0 ~10 15 Durnnny FramefFloor O ~ Frequelloy (Hz) 1ol 10° 10 15 0 [: ummy Upper MassIFloor ; An: -11 ~ 10 15 Frequency (Hz) Figure D-1.5 1: Seat 4 Average Transmissibilities, Economy D- 76

0.02 ~ 0.01 o I 0.02 0.01 o 0.02 ;4 0.01 i Floor 'a O ~ :: ~ ~ . _ O ~ Dummy Frame . ., Dummy Lower Mass 0.04 10 15 0 Suspension 002 J: A o ~ 10 15 Dummy Upper Mass 0.1, 0.05 o 10 15 0 ~ O ~,~ 0 ~ 10 15 Frequerley (Hz) At 10 Frequency (Hz) Figure D-1.52: Seat 5 Average PSD Functions, Economy 15 D- 77

Dum~ny Lower hdassfFloor 10' 100~ 10 ' _ O S;uspensionfFloor Jo 10° 10-1 10 15 0 ~ lol 10° 10.1 Dummy FramelFloor , fit -. 1 0 ~ 10 15 Frequency (Hz) Figure D-1.53 10' .: I, 10 15 Dummy Upper MassfFloor 10° 1Q ' ' o ~ 10 15 Frequency (Hz) Seat 5 Average Transm~ssibilities, Economy D - 78

Floor ~ 0.02 I ~ 0.01 0.02 ~ 0.01 o 10 Suspension it. O ~ Dummy Frame 10 15 0 005 ~. ~ O ~ Dummy Lower Mass 0.04 15 -O 0.05 10 15 Frequency (H~) . . 0.02 /~` ~ 10 15 Dummy Upper Mass ~ 10 15 Frequency (Hz) Figure D-.54: Seat 6 Average PSD Functions, Economy D - 79

10' 104 10 10' 10° 10 SuspensionfFloor . . 'my 14 , O ~ Dummy FramelFlcor · 10' · . 0 ~ 10 Frequency (Hz) 10' 10° 10-1 Dummy Lower 191assIFloor ' '' '1 ~~N 10 15 0 ~ 10 15 Dummy Upper MassIFloor 10° 10 ' 16 0 ~ 10 Frequency (Hz) Figure D-1.55: Seat 6 Average Transmissibilities, Economy D - 80 .

Floor 0.05 I W o 0.04 ;4 0. 02 0.02 ~ 0.01 o Dummy Lower Bless art 0 ~ 10 Suspension :1 l o Dummy Frame ~ ~ - ~ O ~ 0.04 002 15 0 0.05 Lo _: - 10 15 Dummy Upper Mass 1 {~ o 10 15 ~0 ~ Frequency (Hz) 10 15 Frequency (Hz) 10 15 Figure D-:.56: Seat 7 Average PSD Functions, Economy D- 81

10 104 10-1 1ol 10° SuspensionIFloor ~ f O ~ 10 15 Dummy FramelFloor J r 10' 10° 10 10' 100 _ . 10-1 ~ 0 ~ 10 15 ~ 0 Frequency (Hz) Dummy Lower hlassIFloor - ~ 10 15 Dummy Upper MassIFloor it. .: . _ L ~ 10 Frequency (Hz) Figure D-~.57: Seat 7 Average Transm~ssibilities, Economy D - 82 15

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