Automatic collision avoidance system for four-wheel independent drive vehicle by state-dependent Riccati equation

Abstract

In recent years, an automatic collision avoidance system has been put into practical use by various automotive companies. In this study, we propose an automatic collision avoidance system for a four-wheel independent drive vehicle using the state-dependent Riccati equation. By designing the state-dependent weighting functions, a control gain is automatically determined, based on the relative relationship with a preceding vehicle and the system can properly perform automatic braking and automatic steering. Moreover, by updating the state-dependent linear representation obtained from a nonlinear vehicle model in each control cycle, we design a control system in consideration of a change in vehicle dynamics due to vehicle velocity. Therefore, this study verifies the effectiveness of the automatic collision avoidance system using the state-dependent Riccati equation. We compare the performance of the proposed method with constant weight cases. The simulation results show that the proposed method can automatically adjust the control gain and properly avoid a collision by braking and steering to change the relative relationship with a preceding vehicle.

Keywords

• vehicle dynamics
• automatic collision avoidance system
• state-dependent riccati equation
• optimal control
• nonlinear control