Design of Stability Augmentation Systems for Automotive Vehicles

Abstract

The high-speed cruising stability of passenger vehicles may be enhanced with stability augmentation systems. These systems would modify the driver’s steering command to the vehicle’s front wheels, and steer the rear wheels according to measured vehicle conditions such as its yaw-rate. In this simulation study, an explicit driver model is used in the design of these stability augmentation systems. For ease of implementation, only low-order controllers are synthesized using parameter optimization. The high-speed, straight-line stability of a passenger vehicle in a cross-wind is simulated to evaluate steering performance with these controllers. Our results show that stability augmented steering has the potential to improve the directional stability of passenger vehicles.

Vehicle dynamics and control synthesis for four-wheel steering passenger cars

“…So far, the optimal control problems have been studied extensively in vehicle lateral guidance applications. Lateral/directional control laws using the linear quadratic Gaussian (LQG) were proposed in references [3] to [7]. Although the H 2 approach [8] is well-suited to many real systems, it is known that its stability and robustness cannot be guaranteed in the presence of various uncertainties.…”