### Public Meeting with ROHVA, SEA , and CPSC Staff Advance questions/requests of ROHVA Re: ROHVA Presentation to CPSC Staff on November 10, 2011

1. The SSF data presented by ROHVA does not spec ify loading conditions for the various bar graphs . Is it possible f or ROHVA to share those details regarding the data with the CPSC staff? The data is meaningless
without this information. Also, please provide the track width data for each vehicle (A through K) that was
used to calculate the SSF values.

2. Would ROHVA shar e the data (angles and weights) obtained by the “SAE suspension” method that was used
to determine the center of gravity (CG) height measurements for each vehicle ?

3. For the J

- turn data presented by Carr Engineering, please provid e data plots for each J

- turn event conducted
for each vehicle . Please inc lude for each set of data plots the te st vehicle load condition and total weight

. Also, please include plots verses time of corrected Ay, speed, yaw rate, roll rate, and steer angle.

4. In the presentation slide titled “Off

- High way Steering / Vehicle D” Carr E ngineering compares four test conditions for vehicle D. Please provide the load conditions for each of the four test conditions.

5. Several of the presentation slides are titled “Off

- Highway Steering” and prese nt data for steering tests allegedly conducted on a dirt surface. Other ROHVA vehicle dynamics experts have stated that reliable and repeatable steering testing is not possible on dirt surfaces, please quantify the reliability and repeatability of
the ste ering tests conducted on di rt by Carr Engineering Inc. (CEI)

. 6. Please provide wheelbase measurements for each of the vehicles (A through K) tested By CEI.

7. Did Carr Engineering Inc. (CEI) allow the outriggers to contact during the drop throttle J

- Turn tests as indicated in the title of the slides? If so, why did they test to outrigger contact instead of 2 wheel lift per SEA’s test protocol?

8. Why does ROHVA believe the OPEI analysis of the SEA data represents a 19% variation in Ay? The report clearly states tha t the range for ONE vehicle was .03 g which is 19% of the .16 g range for all 11 vehicles tested. If the Ay of the ONE vehicle is .8 g (typical for this class of vehicle) the range of .03 g represents 4% variation...not 19% variation as represented by ROHVA in its presentation.

9. Will CEI share the raw data on the drop throttle J

- turn Ay test variability tests of the vehicle that show a 22% variation in measured Ay (.72 g one run, and .88 g in another run)? Did CEI verify the accuracy of their Ay reading or cal culation by comparing the yaw rate and velocity (V x r) or velocity and radius (V 2 /R) during a steady state circle test?

10. Will CEI share the raw data on the drop throttle J

- turn minimum Ay tests that show CEI’s inability to determine the Ay for 3 of the 11 vehicles tested? Why were the tests run to outrigger contact when such contact prevents measurement of the minimum Ay threshold?

11. Did CEI run drop throttle J

- Turn minimum Ay tests repeatedly to compare maximum Ay just before tip

- up and minimum Ay at tip

- up? SEA used this method to verify the minimum steering magnitudes required for tip

- up...did CEI do the same?

12. Why did ROHVA present a graph of SEA’s data showing vehicle G in the GVW condition in the 30 mph drop
throttle J

- Turn test to the left? The slide point s out .68 g and .72 g Ay points on the plot. The plot was presented in the SEA report alongside other plots of the same vehicle but showing the steer angle, speed, roll angle, and yaw rate. If one reads the roll angle and yaw rate plots, it’s clear that .6 8 g is the Ay value for rollover and the .72 g value is a spike that occurs well after the event.

13. How many drop throt tle J

- Turn runs were performed on Vehicles J and Vehicle B? The graphs showing 1.03 g and 1.10 g Ay defy explanation as those values exceed the SSF value of the vehicles . Is there video of the run that showed a peak Ay of 1.10 g, with sustained (over 1.0 sec) Ay over 1.0 g?

14. Does ROHVA have any reference from NHTSA or any other independent vehicle dynamics experts in support
of oversteer as a desirable vehicle characteristic for a vehicle? Any text book references or SAE papers that refute understeer as a desirable inherent characteristic of the vehicle that should be part of the vehicle’s design?15. Does ROHVA/CEI distinguish between (1) overste er as a vehicle characteristic due to the design of the vehicle and (2) oversteer caused by vehicle kinematics such as drop throttle or braking in a turn or
maneuvers on variable friction surfaces such as dirt or ice?

16. What is the SAE reference that describ es the SAE Suspension Method for CG Height measurement?

17. In addition to the CG height information, would ROHVA share the data on CG lateral and longitudinal locations for each vehicle and loading condition?

18. Please provide information on the outriggers used during the Carr Engineering dynamic tests. What is the weight of the outriggers used? What are the corner weights of the vehicles with the dynamic test instrumentation, outriggers, and driver? Were any measurements made of vehicle CG heights with the

ou triggers mounted on the vehicles? Were any efforts made to adjust vehicle loading during the dynamic tests to match any specific operator/passenger loading conditions?

19. For the J

- turn data presented by Carr Engineering, the ground plane lateral acceleratio ns are plotted. Are the ground plane lateral accelerations measured directly by a sensor, or are they derived from measurements made using a sensor that measures body

- fixed accelerations? If a calculation is used to compute ground plane (roll corrected) l ateral acceleration, please provide the equation(s) used to make the correction. If roll angle is used in the correction equation, please describe in detail the method used to measure or compute roll angle.

20. Please provide a list of all instrumentation (on vehicle sensors and data acquisition equipment) used during the dynamic tests. Also, please provide descriptions of where the instrumentation is mounted to the vehicles during the dynamic tests.

21. Please provide information on the data sampling rates and d ata filtering used for all dynamic tests.

22. The data from the Carr Engineering circle tests appear to be discrete points. Describe the process used for collecting and measuring data for the circle tests. Please be specific on how the data collection is tri ggered, the data collection duration and sampling rate, how the data is averaged or filtered, and how the lateral acceleration is determined (is it V 2 /R as indicated on the graphs).

23. A slide titled “J

- Turn Ay Measurement” from the November 10, 2011 ROHVA pr esentation to CPSC contains a bullet that says, “Results generated by CEI (using SEA methodology) show a wider range of rolling motions.” Please provide more details for the basis of this comment. On the few plots from J

- turn tests provided, the roll rat e traces from CEI do not appear to be too much different from roll rate traces from SEA. Is there a wider range of roll angles? No roll angle plots are provided in the November 10, 2011 presentation.

24. A slide titled “J

- Turn Ay Measurement” from the Nov ember 10, 2011 ROHVA presentation to CPSC contains a bullet that says, “Some vehicles displayed rolling motions which prevented an accurate or reliable measurement of Ay”. Please provide more details for the basis of this comment. Does this issue have to do with the CEI measurements of roll angle only, and how the roll angle is used to compute the Ground Plane
Lateral Acceleration?