Results from Proposed 

ROHVA and OPEI Dynamic Maneuvers 

– Vehicles A, F, and J 

for: 

Consumer Product Safety Commission 

November 2011 

Vehicle Dynamics Division 

7349 Worthington-Galena Rd. 

Columbus, Ohio 43085 
Results from Proposed 

ROHVA and OPEI Dynamic Maneuvers 

– Vehicles A, F, and J 

for: 

Consumer Product Safety Commission 

“These comments are those of S-E-A, Ltd. staff, and they have not been reviewed 

or approved by, and may not necessarily reflect the views of, the Commission.” 

Report prepared by Gary J. Heydinger, Ph.D., P.E., 

with primary support from Ron Bixel, Hank Jebode, 

Elaine Peterman and Anmol Sidhu 

Vehicle Dynamics Division 

7349 Worthington-Galena Rd. 

Columbus, Ohio 43085 
TABLE OF CONTENTS 

1. OVERVIEW .................................................................................................................. 1

2. DYNAMIC TESTING................................................................................................... 2

3. DISCUSSION OF TEST RESULTS ............................................................................. 4

Appendix A: Results From Constant Steer Tests....................................................................... A-1 

Appendix B: Results From Dropped Throttle J-Turn Tests........................................................B-1 

Appendix C: Measurements Used to Determine Target Steering Wheel Angles 

for ROHVA Constant Steer Tests .........................................................................C-1 
1

1. OVERVIEW 

This report contains results from measurements made by S-E-A, Ltd., for the U.S. Consumer 

Product Safety Commission (CPSC) under contract CPSC-S-10-0014, Modification 0004. This 

report covers two of the objectives of Modification 0004, namely: 

• Conduct constant steer turns on an asphalt surface at a set turn radius of 25 ft. Increase 

speed until vehicle limit is achieved and dynamic data are recorded. (For this objective, 

tests were performed to evaluate a dynamic test protocol recommended by the 

Recreational Off-Highway Vehicle Association (ROHVA) in their December 22, 2010, 

Canvass Draft of the proposed American National Standard for Recreational OffHighway Vehicles.) 

• Conduct J-turns on an asphalt surface using drop throttle techniques and initiating 180 

degrees of steering at a set speed of 20 mph. Use a steering controller to achieve accurate 

steer angles and consistent steering rate. (For this objective, tests were performed to 

evaluate a dynamic test protocol recommended by the Outdoor Power Equipment 

Institute (OPEI). On January 11, 2011, the CPSC staff received the second canvass draft 

of ANSI/OPEI B71.9-20XX, American National Standard for Multipurpose Off-Highway 

Utility Vehicles.) 

S-E-A has conducted laboratory testing and dynamic testing on 10 recreational off-highway 

vehicles (ROVs) for CPSC. A previous report titled, “Vehicle Characteristics Measurements of 

Recreational Off-Highway Vehicles,” containing measurement results for nine vehicles (Vehicles 

A through I), was published in April 2011.1

 A second report titled, “Vehicle Characteristics 

Measurements of Recreational Off-Highway Vehicles – Additional Results for Vehicle J,”

contains results for measurements made on the tenth recreational off-highway vehicle.2

 The 

vehicles tested under this portion of the contract modification are Vehicles A, F, and J; and they 

were selected for testing by CPSC. 

This report contains three main sections and three appendices that contain test results. The three 

report sections are Overview, Dynamic Testing, and Discussion of Test Results. Appendix A 

contains test results from the constant steer tests; Appendix B contains test results from the 

dropped throttle J-turn tests; and Appendix C contains measurements used to determine target 

steering wheel angles for the ROHVA constant steer tests. 

 

1 Vehicle Characteristics Measurements of Recreational Off-Highway Vehicles, CPSC Contract CPSC-S-10-0014, 

S-E-A, Ltd. Report to CPSC, April 2011. http://www.cpsc.gov/library/foia/foia11/os/rov.pdf. 

2 Vehicle Characteristics Measurements of Recreational Off-Highway Vehicles – Additional Results for Vehicle J, 

CPSC Contract CPSC-S-10-0014, S-E-A, Ltd. Report to CPSC, August 2011. 

http://www.cpsc.gov/PageFiles/93928/rovj.pdf. 
2

2. DYNAMIC TESTING 

All of the dynamic tests were performed in one loading configuration, namely: 

1. Operator, Instrumentation, and Outriggers 

This dynamic testing loading condition was specified to be the vehicle curb condition, 

plus the weight of the actual test driver, test instrumentation (including measurement 

transducers, data acquisition computer, S-E-A’s Automated Steering Controller (ASC), 

ASC controller box, and ASC battery box), and safety outriggers. Table 1 lists the 

nominal weights of the test driver and test equipment, including the outriggers. The total 

weight of the driver, instrumentation, and safety outriggers is nominally 426 lb, which is 

the same weight as two 213 lb occupants. This dynamic loading condition was designed 

to match as closely as possible the total weight of the Operator and Passenger (each 

weighing nominally 213 lb) loading condition used during previous laboratory testing. 

The test equipment and safety outriggers were adjusted so that the vertical, lateral, and 

longitudinal CG positions of the dynamic loading configurations would match those of 

Operator and Passenger loading configurations as closely as practically possible. This 

dynamic loading configuration is also referred to as the representative Operator and 

Passenger loading configuration. 

Table 1: Weights of Driver and Test Equipment 

Object Weight (lb) 

 Test Driver with Helmet 182 

 ASC Handwheel Unit 34 

 ASC Battery Box 27 

 ASC Electronics Box and Cables 25 

 S-E-A Data Acquisition Computer 10 

 Auxiliary 12V Battery 25 

 RT3002 GPS/IMU, Antenna, and Cables 10 

 S-E-A Power Distribution Box and Misc. Straps 7 

 CPSC Triangulated Aluminum Safety Outriggers 106 

Total Nominal Weight 426 

The same test driver, test instrumentation, and CPSC outriggers that were used for previous 

testing of Vehicles A through J were used for the testing. 

The tests on Vehicles A and F were conducted on April 6, 2011, and the tests on Vehicle J were 

conducted on May 20, 2011. With one exception, all of the maneuvers were conducted on the 

flat, dry asphalt surface of TRC’s Vehicle Dynamics Area (VDA). The exception is that the 

constant steer tests for Vehicle J were conducted on a flat asphalt surface near the TRC Winding 

Road Course (the VDA was not available when these tests were conducted). 

Table 2 lists the instrumentation used during the dynamic testing. The RT3002 was mounted 
3

near the CG of the vehicle. Nonetheless, the longitudinal, lateral, and vertical offsets from the 

center of the RT3002 to the actual vehicle CG location were measured and entered into the 

RT3002 system software. This information was used to translate the measured quantities to 

those at the CG of the vehicle. The longitudinal and lateral accelerations measured and reported 

here are accelerations parallel to the road plane, as opposed to vehicle body fixed accelerations. 

The vertical acceleration is the acceleration orthogonal to the longitudinal and lateral 

accelerations. 

Table 2: Instrumentation Used During Dynamic Testing 

Transducer Measurement Range Accuracy or 

Linearity

Longitudinal, Lateral, and Vertical 

Accelerations ± 10 g 0.1% 1σ

Roll, Pitch, and Yaw Rates ± 100 deg/s 0.1% 1σ

Speed No Limit 

Specified 0.2% 1σ

Roll and Pitch Angles No Limit 

Specified 0.03° 1σ

Oxford Technical 

Solutions 

RT3002 Inertial and

GPS Navigation 

System 

Vehicle Heading and Sideslip Angle No Limit 

Specified 0.1° 1σ

Encoder on 

S-E-A, Ltd. ASC Steering Wheel Angle + 800 deg + 0.25 deg 
4

3. DISCUSSION OF TEST RESULTS 

Constant Steer Tests 

The constant steer tests involve turning the steering wheel to a fixed steer angle and then slowly 

increasing the speed of the vehicle from zero mph. The ROHVA protocol is to apply steady 

throttle input until the vehicle achieves a corrected lateral acceleration of 0.6 g; additional throttle 

input does not result in increased vehicle speed; or a two-wheel lift of two inches or more occurs. 

However, for these tests conducted for CPSC, throttle input was increased up to the limit of 

vehicle performance. In this case, resulting in a two-wheel lift, maximum speed, or spinout; and 

there was no attempt made to stop the tests at 0.6 g of corrected lateral acceleration. 

The fixed steering magnitudes used for these tests are based on the geometric Ackerman steering 

required to negotiate a circular turn of 25 ft radius. In their December 22, 2010, Canvass Draft 

report, ROHVA describes a method for determining the geometric Ackerman steering angle, and 

they refer to this angle as the Target Steering Wheel Angle. The ROHVA method to determine 

Target Steering Wheel Angle was used for this testing; and the measurements made to determine 

the Target Steering Wheel Angles for the three vehicles tested are contained in Appendix C. 

Appendix A contains the results from the constant steer tests. There are three pages of results for 

each of the three vehicles. The first page for each vehicle contains results from five constant 

steer tests conducted in the clockwise direction; and the second page for each vehicle contains 

results from tests conducted in the counterclockwise direction. The third page for each vehicle 

contains two graphs: the top graph is a plot of path radius versus corrected lateral acceleration, 

and the bottom graph is a plot of roll angle versus corrected lateral acceleration. The top graph is 

one of the typical plotting formats suggested by SAE J2663

 for evaluating vehicle understeer 

gradient from a constant steer test. 

Each of the first two pages for each vehicle in Appendix A contains time domain plots of Steer 

Angle, (Corrected) Lateral Acceleration, Speed, Roll Angle, and Yaw Rate. All of the dynamic 

test data are sampled at 100 Hz. For the constant steer test results, the data shown were digitally 

low-pass filtered to 1.0 Hz using a phaseless, eighth-order, Butterworth filter. The time domain 

data shown for each vehicle contain data from 2.0 seconds prior to the time the steering was 

ramped to the Target Steering Wheel Angle, until 50.0 seconds after the start of the steering 

input. Notice that the steering angle is positioned to the Target Steering Wheel Angle and held 

there prior to the time at which the vehicle begins to speed up. The steering input is applied and 

held by S-E-A’s ASC and the test driver controls the vehicle speed. The thin black lines for the 

CW and CCW tests show the range of data from –2.0 to 50.0 seconds. The thicker colored lines 

indicate the range of data from –2.0 seconds until a corrected lateral acceleration of 0.6 g is 

achieved. 

On the third page for each vehicle, the top graphs contain understeer gradient characteristic 

curves showing path radius (path curvature) as a function of lateral acceleration. The “Radius” is 

computed using the relationship below, which is based on a vehicle operating at a steady-state 

condition. 

 

3

 SAE J266, Surface Vehicle Recommended Practice, Steady-State Directional Control Test Procedures for 

Passenger Cars and Light Trucks, 1996. 
5

r

V

Radius =

where: 

Radius = Path Curvature (ft) 

V = Vehicle Speed (ft/sec) 

r = Yaw Rate (rad/sec) 

These graphs contain data for all runs conducted in both the clockwise and counterclockwise 

directions. On these graphs, the thin colored lines show the raw data, and the thicker blue lines 

show second-order polynomial curve fits to the raw data. The range of raw data and curve fit 

data used is from a lateral acceleration level of 0.05 g up to the point where the vehicles reached 

their maximum speeds during each test. 

Regarding conducting constant steer tests for passenger vehicles, SAE J2664

 states: “... speed 

may be steadily increased, at a rate not exceeding 1.5 km/h per second (0.93 mph per second) 

...”. At speeds beyond the range of 5 to 8 mph, the rates of speed increase during the constant 

steer tests conducted are much less than the J266 recommended maximum rate. 

Based on previous testing used to quantify understeer, all three vehicles (A, F, and J) were found 

to transition from understeer to oversteer during constant radius (100 ft) circle tests and constant 

speed (30 mph) tests. For the understeer gradient characteristic curves from the constant steer 

tests shown in Appendix A, a line with a slope of zero represents a neutral steer condition, the 

line with a positive slope represents an understeer condition, and a line with a negative slope 

represents an oversteer condition. Notice that a negative slope on these graphs indicates that the 

vehicle path follows a smaller path radius as the lateral acceleration increases. The red circles on 

these graphs show the radius (25 ft), based on the geometric Ackerman steering angle. The 

constant steer tests show that Vehicle A exhibited understeer at low lateral acceleration levels, 

and then transitioned to oversteer in the range of 0.25 to 0.30 g (Page A-3). Vehicle F exhibited 

oversteer at all lateral acceleration levels (Page A-6). Vehicle J exhibited near neutral steer at 

low lateral acceleration levels and then transitioned to oversteer (Page A-9). 

On the third page for each vehicle, the bottom graphs of roll angle versus corrected lateral 

acceleration are useful for determining when the roll angle of the vehicle increased toward 

impending tip-up. These graphs contain data for all runs conducted in both the clockwise and 

counterclockwise directions. On these graphs, the range of data shown is from a lateral 

acceleration level of 0.05 g up to the point where the vehicles reached their maximum speeds 

during each test. For Vehicle A, the bottom graph on Page A-3 shows that the tip-ups occurred 

at lateral accelerations slightly below 0.6 g in both the clockwise and counterclockwise 

directions. The graph on Page A-6 for Vehicle F shows that the vehicle did not tip-up onto the 

outriggers while the vehicle speed was increasing up to its maximum value during each test. For 

this vehicle, soon after the driver reduced the vehicle speed from its maximum, the yaw rate and 

lateral acceleration increased, the path curvature decreased, and the vehicle tipped up onto the 

 

4

Ibid. 
6

outriggers. For Vehicle J, the bottom graph on Page A-9 shows that the tip-ups occurred at 

lateral accelerations slightly below 0.6 g in the clockwise direction. In the counterclockwise 

direction, where the vehicle spun out, the roll angles were not large, and no tip-ups occurred. To 

minimize rear tire wear that occurred as a result of the spinouts, only four tests were conducted 

for Vehicle J in the counterclockwise direction. 

As mentioned previously, the ROHVA protocol is to apply steady throttle input until the vehicle 

achieves a corrected lateral acceleration of 0.6 g; additional throttle input does not result in 

increased vehicle speed, or a two-wheel lift of two inches or more occurs. In practice, 

segregating these three test-ending conditions from one another can be difficult to realize. 

Table 3 contains a summary of the constant steer tests conducted. The third column of Table 3 

lists the ROHVA end conditions achieved for each vehicle in the clockwise and 

counterclockwise directions. All of the end conditions for Vehicle A in both turn directions are 

two-wheel lift (Pages A-1 and A-2). All of the end conditions for Vehicle F in both turn 

directions are maximum speed; however, this vehicle tipped up onto the safety outriggers once 

the driver slowed down the vehicle at the end of each run (Pages A-4 and A-5). All of the end 

conditions of Vehicle J in the clockwise direction are two-wheel lift (Page A-7). However, all of 

the end conditions for Vehicle J in the counterclockwise direction are maximum speed spinouts, 

characterized by the high yaw rates at the end of the maneuvers (Page A-8). 

During a constant steer test using the ROHVA protocol, it is difficult to monitor in real time 

precisely when 0.6 g of corrected lateral acceleration is achieved. It is difficult for a test driver, 

an off-board test observer, or using analytical methods to determine when the onset of a steady 

magnitude of 0.6 g of corrected lateral acceleration is first achieved. On-board accelerometers 

generally have high frequency content (noise) that makes getting real-time steady acceleration 

readings difficult. Also, sensors that measure body-fixed lateral acceleration need to be 

“corrected” by compensation for roll angle, which may hinder real-time monitoring. Corrected 

lateral acceleration can also be computed from the product of vehicle speed and yaw rate. These 

signals are also prone to typical measurement noise and actual vehicle oscillations during these 

tests when the vehicles are near their limits of performance in the range of 0.6 g. For these 

reasons, it is very difficult to repeatedly end the proposed ROHVA maneuver at 0.6 g of 

corrected lateral acceleration. 

For Vehicle A, two-wheel lift leading to outrigger contact started at corrected lateral 

accelerations just below 0.6 g in both the right and left steer directions. For this vehicle, twowheel lift of two inches or more occurs very close to 0.6 g. For Vehicle F, in both the right and 

left steer directions, the driver sensed that the vehicle was at its maximum speed, and he slowed 

down to end the maneuver. As a result of dropping the throttle, the vehicle load transferred 

forward, yaw rate and lateral acceleration increased, the path curvature decreased, and the vehicle 

tipped up onto the outriggers. For this vehicle, maximum speed occurred very near 0.6 g; and 

slowing down from maximum speed resulted in tip-up onto the outriggers. For Vehicle J, in the 

right steer (clockwise) direction, two-wheel lift leading to outrigger contact started at corrected 

lateral accelerations below 0.6 g. However, in the left steer (counterclockwise) direction, the 

vehicle did not tip up, but rather, it spun out with the onset of spin out very near a lateral 

acceleration of 0.6 g. 
7

The Vehicle A maneuver end conditions were two-wheel lift near maximum speed and 0.6 g 

lateral acceleration in both steer directions. The Vehicle F end conditions were maximum speed 

in both directions (which was also very close to 0.6 g lateral acceleration); but the vehicle tipped 

up onto the outriggers soon after the driver slowed down to end the maneuver. One of the 

Vehicle J end conditions was two-wheel lift in the right steer direction and maximum speed in 

the left steer direction. For this sample of three vehicles, in several cases multiple test end 

conditions occurred at nearly the same time, for one of the vehicles, a maximum speed test end 

condition was followed by a two-wheel lift end condition, and for one of the vehicles the test end 

conditions differed in the right and left steer directions. For these reasons, it appears that the 

proposed ROHVA test protocol end conditions can be difficult to segregate from one another and 

the test outcomes can differ for a single vehicle, depending on the direction of steer. 

Column four of Table 3 lists the ROHVA pass or fail outcomes for each vehicle in both steer 

directions. Vehicle A failed in both steer directions; Vehicle F passed in both directions (but 

these were followed by a failed conditions as the driver slowed down at the end of each run); and 

Vehicle J failed in the clockwise direction and passed in the counterclockwise direction. 

Table 3: Summary of Constant Steer Tests 

Using Ackerman Geometric Steering Magnitude for 25 ft Radius Path

Vehicle Turn Direction 

Test End 

Condition / 

Limit Response 

ROHVA 

Test Pass/Fail 

Outcome

Right (CW) Two-wheel Lift Fail 

Vehicle A 

Left (CCW) Two-wheel Lift Fail 

Right (CW) Maximum Speed* Pass**

Vehicle F 

Left (CCW) Maximum Speed* Pass**

Right (CW) Two-wheel Lift Fail 

Vehicle J 

Left (CCW) Maximum Speed / 

Spinout Pass 

*Maximum speed occurred very near 0.6 g of corrected lateral acceleration for Vehicle F. 

**Two-wheel lift occurred for Vehicle F after the driver slowed from maximum speed at the end of the test. 
8

Dropped Throttle J-Turn Tests 

J-turn tests, often referred to as step steer tests, involve imparting a rapid steering input up to a 

fixed magnitude while the vehicle is traveling along a straight path. For the dropped throttle Jturn tests, the test driver drove each vehicle along a straight-line path at a speed slightly above 

the desired test speed. He then dropped the throttle and triggered the ASC to initiate the steering 

input precisely when the vehicle speed reached the desired test speed. 

The OPEI test protocol is to conduct the dropped throttle J-turn test at 20 mph and to use a 

steering magnitude of 180 degrees. A vehicle subjected to the proposed J-turn test would be 

considered to have acceptable lateral stability if it did not experience two-wheel lift of two inches 

or more during the test. 

For these tests conducted for CPSC, steering magnitudes of 180 degrees and steering rates of 500 

deg/sec were used for all of the J-turn tests. Additionally, if a vehicle did not tip up at 20 mph, 

the test speed was increased in one mph increments to determine the speed at which moderate 

two-wheel lift would occur. In this case, moderate two-wheel lift means that at least two inches 

of simultaneous two-wheel lift occurred. 

Appendix B contains the results from the dropped throttle J-turn tests. Each page in Appendix B 

contains time domain plots of Steer Angle, (Corrected) Lateral Acceleration, Speed, Roll Angle, 

and Yaw Rate. All of the dynamic test data are sampled at 100 Hz. For the J-turn test results, the 

data shown were digitally low-pass filtered to 5.0 Hz, using a phaseless, eighth-order, 

Butterworth filter. The time domain data shown for each vehicle contains data from 0.5 seconds 

prior to the time of the J-turn steering until 6.0 seconds after the start of the steering input. 

Notice that once the steering angle reaches 180 degrees it is held there for a dwell time of 4.0 

seconds. The steering input was applied and held by S-E-A’s ASC, and the steering was 

triggered at the precise desired speed by a speed signal sent to the ASC. 

There are four pages of results each for Vehicles A and F, and two pages for Vehicle J. The first 

two pages for Vehicles A and F contain results from three right turn, J-turn tests; and the third 

and forth pages contain results from three left turn J-turn tests. For Vehicles A and F, three 

repeat tests at 20 mph were conducted, and these are the results shown on the first and third 

pages for these two vehicles. These pages showing repeat runs conducted at 20 mph (Pages B-1 

and B-3 for Vehicle A, and Pages B-5 and B-7 for Vehicle F) indicate that the vehicle responses 

and test outcomes from the dropped J-turn maneuvers are very repeatable. 

Table 4 contains a summary of the dropped throttle J-turn tests conducted. As indicated in the 

forth column of Table 4, all three of the vehicles tested passed the proposed OPEI test since they 

did not experience two-wheel lift of two inches or more during the tests conducted at initial test 

speeds of 20 mph. 

The third column of Table 4 shows the initial test speed that did result in two-wheel lift of two 

inches or more during the dropped throttle J-turn tests. As indicated in the table, all three of the 

vehicles experienced two-wheel lift of two inches during the tests conducted at a minimum speed 

of 21 mph, in either the right or left turn direction. Results from the tests conducted at initial test 

speeds above 20 mph, including the ones that resulted in moderate two-wheel lift (wheel lift of 
9

two inches or more), are contained in Appendix B. The legends on the graphs in Appendix B 

indicate the test outcomes for each run. The outcomes listed are: Rear WL (only rear wheel lift), 

Slight 2WL (two-wheel lift of less than two inches), 2WL (two-wheel lift of two inches or more), 

and Outriggers (wheel lift much greater than two inches and high enough to cause contact of the 

safety outriggers with the test surface). 

Table 4: Summary of Dropped Throttle J-Turns 

with 180 deg Steering at 500 deg/s 

Vehicle Turn Direction 

Initial Speed 

Required for 

Moderate 2WL

OPEI 

20 mph Test 

Pass/Fail 

Outcome 

Right 22 mph Pass 

Vehicle A 

Left 21 mph Pass 

Right 21 mph Pass 

Vehicle F 

Left 22 mph Pass 

Right 21 mph Pass 

Vehicle J 

Left 23 mph Pass 
Appendix A: Results From Constant Steer Tests 

A-1

0 10 20 30 40 50

0

5

10

15

20

Speed (mph)

Runs: 105, 106, 107, 108 and 110

0 10 20 30 40 50

0

50

100

150

200

Steer Angle (deg)

Vehicle A - ROHVA CW Constant Steer Tests

0 10 20 30 40 50

0

0.1

0.2

0.3

0.4

0.5

0.6

Lateral Acceleration (g)

Time (sec)

0 10 20 30 40 50

-20

-15

-10

-5

0

5

Roll Angle (deg)

Outrigger Contact

All Runs

0 10 20 30 40 50

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)
Appendix A: Results From Constant Steer Tests 

A-2

0 10 20 30 40 50

0

5

10

15

20

Speed (mph)

Runs: 111, 112, 113, 114 and 115

0 10 20 30 40 50

-200

-150

-100

-50

0

Steer Angle (deg)

Vehicle A - ROHVA CCW Constant Steer Tests

0 10 20 30 40 50

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

Lateral Acceleration (g)

Time (sec)

0 10 20 30 40 50

-5

0

5

10

15

20

Roll Angle (deg)

Outrigger Contact

All Runs

0 10 20 30 40 50

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)
Appendix A: Results From Constant Steer Tests 

A-3

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

-40

-30

-20

-10

0

10

20

30

40

Ay (g)

Radius (ft)

Vehicle A - ROHVA Constant Steer Tests

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

-10

-8

-6

-4

-2

0

2

4

6

8

10

Ay (g)

Roll Angle (deg)

Vehicle A - ROHVA Constant Steer Tests
Appendix A: Results From Constant Steer Tests 

A-4

0 10 20 30 40 50

0

5

10

15

20

Speed (mph)

Runs: 204, 205, 206, 207 and 208

0 10 20 30 40 50

0

50

100

150

200

Steer Angle (deg)

Vehicle F - ROHVA CW Constant Steer Tests

0 10 20 30 40 50

0

0.1

0.2

0.3

0.4

0.5

0.6

Lateral Acceleration (g)

Time (sec)

0 10 20 30 40 50

-20

-15

-10

-5

0

5

Roll Angle (deg)

Outrigger Contact

All Runs

0 10 20 30 40 50

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)
Appendix A: Results From Constant Steer Tests 

A-5

0 10 20 30 40 50

0

5

10

15

20

Speed (mph)

Runs: 209, 210, 211, 212 and 213

0 10 20 30 40 50

-200

-150

-100

-50

0

Steer Angle (deg)

Vehicle F - ROHVA CCW Constant Steer Tests

0 10 20 30 40 50

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

Lateral Acceleration (g)

Time (sec)

0 10 20 30 40 50

-5

0

5

10

15

20

Roll Angle (deg)

Outrigger Contact

All Runs

0 10 20 30 40 50

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)
Appendix A: Results From Constant Steer Tests 

A-6

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

-40

-30

-20

-10

0

10

20

30

40

Ay (g)

Radius (ft)

Vehicle F - ROHVA Constant Steer Tests

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

-10

-8

-6

-4

-2

0

2

4

6

8

10

Ay (g)

Roll Angle (deg)

Vehicle F - ROHVA Constant Steer Tests
Appendix A: Results From Constant Steer Tests 

A-7

0 10 20 30 40 50

0

5

10

15

20

Speed (mph)

Runs: 1910, 1913, 1914, 1915 and 1920

0 10 20 30 40 50

0

50

100

150

200

Steer Angle (deg)

Vehicle J - ROHVA CW Constant Steer Tests

0 10 20 30 40 50

0

0.1

0.2

0.3

0.4

0.5

0.6

Lateral Acceleration (g)

Time (sec)

0 10 20 30 40 50

-20

-15

-10

-5

0

5

Roll Angle (deg)

Outrigger Contact

All Runs

0 10 20 30 40 50

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)
Appendix A: Results From Constant Steer Tests 

A-8

0 10 20 30 40 50

0

5

10

15

20

Speed (mph)

Runs: 1916, 1917, 1918 and 1919

0 10 20 30 40 50

-200

-150

-100

-50

0

Steer Angle (deg)

Vehicle J - ROHVA CCW Constant Steer Tests

0 10 20 30 40 50

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

Lateral Acceleration (g)

Time (sec)

0 10 20 30 40 50

-5

0

5

10

15

20

Roll Angle (deg)

0 10 20 30 40 50

-150

-100

-50

0

Yaw Rate (deg/sec)

Time (sec)

Spinout

All Runs
Appendix A: Results From Constant Steer Tests 

A-9

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

-40

-30

-20

-10

0

10

20

30

40

Ay (g)

Radius (ft)

Vehicle J - ROHVA Constant Steer Tests

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

-10

-8

-6

-4

-2

0

2

4

6

8

10

Ay (g)

Roll Angle (deg)

Vehicle J - ROHVA Constant Steer Tests
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-1

0 2 4 6

0

50

100

150

200

Steer Angle (deg)

Time (sec)

Vehicle A - J-Turn Right

0 2 4 6

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 126, 127 and 128

0 2 4 6

-15

-10

-5

0

5

Roll Angle (deg)

0 2 4 6

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

20 mph: Rear WL

20 mph: Rear WL
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-2

0 2 4 6

0

50

100

150

200

Steer Angle (deg)

Time (sec)

Vehicle A - J-Turn Right

0 2 4 6

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 128, 129 and 130

0 2 4 6

-15

-10

-5

0

5

Roll Angle (deg)

0 2 4 6

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

21 mph: Slight 2WL

22 mph: Outrigger
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-3

0 2 4 6

-200

-150

-100

-50

0

Steer Angle (deg)

Time (sec)

Vehicle A - J-Turn Left

0 2 4 6

-0.8

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 132, 133 and 134

0 2 4 6

-5

0

5

10

15

Roll Angle (deg)

0 2 4 6

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)

20 mph: Slight 2WL

20 mph: Slight 2WL

20 mph: Slight 2WL
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-4

0 2 4 6

-200

-150

-100

-50

0

Steer Angle (deg)

Time (sec)

Vehicle A - J-Turn Left

0 2 4 6

-0.8

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 134, 135 and 136

0 2 4 6

-5

0

5

10

15

Roll Angle (deg)

0 2 4 6

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)

20 mph: Slight 2WL

21 mph: Outrigger

22 mph: Outrigger
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-5

0 2 4 6

0

50

100

150

200

Steer Angle (deg)

Time (sec)

Vehicle F - J-Turn Right

0 2 4 6

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 227, 228 and 229

0 2 4 6

-15

-10

-5

0

5

Roll Angle (deg)

0 2 4 6

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

20 mph: Rear WL

20 mph: Rear WL
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-6

0 2 4 6

0

50

100

150

200

Steer Angle (deg)

Time (sec)

Vehicle F - J-Turn Right

0 2 4 6

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 229, 230 and 231

0 2 4 6

-15

-10

-5

0

5

Roll Angle (deg)

0 2 4 6

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

21 mph: 2WL

22 mph: Outrigger
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-7

0 2 4 6

-200

-150

-100

-50

0

Steer Angle (deg)

Time (sec)

Vehicle F - J-Turn Left

0 2 4 6

-0.8

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 232, 233 and 234

0 2 4 6

-5

0

5

10

15

Roll Angle (deg)

0 2 4 6

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

20 mph: Rear WL

20 mph: Rear WL
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-8

0 2 4 6

-200

-150

-100

-50

0

Steer Angle (deg)

Time (sec)

Vehicle F - J-Turn Left

0 2 4 6

-0.8

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 234, 235 and 236

0 2 4 6

-5

0

5

10

15

Roll Angle (deg)

0 2 4 6

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

21 mph: Slight 2WL

22 mph: Outrigger
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-9

0 2 4 6

0

50

100

150

200

Steer Angle (deg)

Time (sec)

Vehicle J - J-Turn Right

0 2 4 6

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 1984, 1985 and 1956

0 2 4 6

-15

-10

-5

0

5

Roll Angle (deg)

0 2 4 6

0

20

40

60

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

21 mph: 2WL

22 mph: Outrigger
Appendix B: Results From Dropped Throttle J-Turn Tests 

B-10

0 2 4 6

-200

-150

-100

-50

0

Steer Angle (deg)

Time (sec)

Vehicle J - J-Turn Left

0 2 4 6

-0.8

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

Lateral Acceleration (g)

Time (sec)

0 2 4 6

0

10

20

30

Speed (mph)

Runs: 1986, 1987 and 1988

0 2 4 6

-5

0

5

10

15

Roll Angle (deg)

0 2 4 6

-60

-40

-20

0

Yaw Rate (deg/sec)

Time (sec)

20 mph: Rear WL

23 mph: 2WL

24 mph: Outrigger
Appendix C: Measurements Used to Determine Target Steering Wheel Angles for ROHVA Constant Steer Tests 

 C-1

-400 -300 -200 -100 0 100 200 300 400

-40

-30

-20

-10

0

10

20

30

40

Right Wheel Steer Angle (deg)

Vehicle A - Steering Ratio - ROHVA Method - 25 ft Radius Circle

Right Steering = 182.4 deg

Left Steering = -193.1 deg

Wheelbase = 6.26 ft

Circle Radius = 25.0 ft

Ackerman Angle = 14.1 deg

-400 -300 -200 -100 0 100 200 300 400

-40

-30

-20

-10

0

10

20

30

40

Steering Wheel Angle (deg)

Left Wheel Steer Angle (deg)

Right Steering = 192.1 deg

Left Steering = -182.6 deg

Target Steering Wheel Angle = 187.5 deg
Appendix C: Measurements Used to Determine Target Steering Wheel Angles for ROHVA Constant Steer Tests 

 C-2

-400 -300 -200 -100 0 100 200 300 400

-40

-30

-20

-10

0

10

20

30

40

Right Wheel Steer Angle (deg)

Vehicle F - Steering Ratio - ROHVA Method - 25 ft Radius Circle

Right Steering = 210.6 deg

Left Steering = -220.6 deg

Wheelbase = 6.25 ft

Circle Radius = 25.0 ft

Ackerman Angle = 14.0 deg

-400 -300 -200 -100 0 100 200 300 400

-40

-30

-20

-10

0

10

20

30

40

Steering Wheel Angle (deg)

Left Wheel Steer Angle (deg)

Right Steering = 218.4 deg

Left Steering = -209.7 deg

Target Steering Wheel Angle = 214.8 deg
Appendix C: Measurements Used to Determine Target Steering Wheel Angles for ROHVA Constant Steer Tests 

 C-3

-400 -300 -200 -100 0 100 200 300 400

-40

-30

-20

-10

0

10

20

30

40

Right Wheel Steer Angle (deg)

Vehicle J - Steering Ratio - ROHVA Method - 25 ft Radius Circle

Right Steering = 179.3 deg

Left Steering = -196.5 deg

Wheelbase = 6.35 ft

Circle Radius = 25.0 ft

Ackerman Angle = 14.3 deg

-400 -300 -200 -100 0 100 200 300 400

-40

-30

-20

-10

0

10

20

30

40

Steering Wheel Angle (deg)

Left Wheel Steer Angle (deg)

Right Steering = 202.0 deg

Left Steering = -186.7 deg

Target Steering Wheel Angle = 191.1 deg