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Vehicle Stability Considerations with Automatic and Four Wheel Steering Systems
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Abstract
Automatic and four wheel steering control laws are often developed from the performance point of view to optimize rapid response. Under linear tire operating conditions (i.e., maneuvering at less than .5g's) both performance and safety conditions can be simultaneously met. Under severe operating conditions, such as might be encountered during crash avoidance maneuvering, tire characteristics can change dramatically and induce directional dynamic instability and spinout. The challenge in automatic and four wheel steering system design is to achieve a compromise between performance and safety.
This paper will describe analyses carried out with a validated vehicle dynamics computer simulation that shed some light on the vehicle and control characteristics that influence tradeoffs between performance and safety. The computer simulation has been validated against field test data from twelve vehicles including passenger cars, vans, pickup trucks and utility vehicles. The simulation includes a very complete tire model for representing the effects of skidding under hard maneuvering conditions, and has been shown to properly represent spinout conditions that occurred during the validation field testing.
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Allen, R., Myers, T., and Rosenthal, T., "Vehicle Stability Considerations with Automatic and Four Wheel Steering Systems," SAE Technical Paper 931979, 1993, https://doi.org/10.4271/931979.Also In
References
- IVHS America “Strategic Plan for Intelligent Vehicle-Highway Systems in the United States,” Apr. 24 1992
- McRuer, D.T. Ashkenas I.L. Graham D. Aircraft Dynamics and Automatic Control Princeton University Press 1973
- Myers, T.T. McRuer D.T. Johnston D.E. Flying Qualities and Control Systems Characteristics for Superaugmented Aircraft NASA CR-170419 Dec. 1984
- Myers, T.T. Space Shuttle Flying Qualities and Criteria Assessment NASA CR-4049m Mar. 1987
- Sano, S. Furukawa Y. Shiraishi S. “Four-Wheel Steering System with Rear Wheel Steer Angle Controlled as a Function of Steering Wheel Angle,” SAE Paper No. 860625 Feb. 1986
- Sato, H. Hirota A. et al. “Dynamic Characteristics of a Whole Wheel Steering Vehicle with Yaw Velocity Feedback Rear Wheel Steering,” Paper C124/83, Proceedings of a conference on Road Vehicle Handling Inst. of Mechanical Engineers London 147 156 May 1983
- Allen, R.W. Szostak Henry T. et al. “Characteristics Influencing Ground Vehicle Lateral/Directional Dynamic Stability,” SAE Paper 910234 SAE SP-861 Feb. 1991
- Yamamoto, M. “Active Control Strategy for Improved Handling and Stability,” SAE Paper 911902 SAE Special Publication SP-878 21 32
- Stevens, W. Leasure W. Saxton L. “Automated Highway System (AHS) Program,” third annual IVHS America Meeting Washington, DC Apr. 1993
- Thompson, P.M. Electric Modern Design Methods for Practical Flight Control Systems Technology, Inc. 14 Sept. 1992
- Thompson, P.M. Myers T.T. Aponso B.L. et al Practical Applications of Multi-Variable Robustness Methods to Advanced Flight Control Systems Technology, Inc. Sept. 1988
- Allen, R.W. Rosenthal T.J. et al. “Validation of Ground Vehicle Computer Simulations Developed for Dynamic Stability Analysis,” SAE Paper 920054 SAE SP-909 Feb. 1992
- Allen, R.W. Szostak H.T. Rosenthal T.J. “Steady State and Transient Analysis of Ground Vehicle Handling,” SAE Paper No. 870495 Feb. 1987
- Allen, R.W. Szostak H.T. et al. Analytical Modeling of Driver Response in Crash Avoidance Maneuvering: Vol. I - Technical Background National Highway Traffic Safety Administration Apr. 1988
- Allen, R.W. Rosenthal T.J. “Performance and Safety Considerations in Four Wheel Steering Control Laws,” third annual meeting of IVHS America Washington, DC Apr. 1993