考虑线控转向非线性和不确定性的转向角控制

Steering Angle Control of Steer by Wire Systems Considering Nonlinear Characteristic and Uncertainty Parameters

摘要:

研究了线控转向系统的转向轮转角跟踪控制.控制算法的设计建立在对轮胎回正力矩的非线性特性以及系统参数不确定性进行分析的基础上，并考虑了执行器力矩受限的情况.基于一种条件积分方法，设计前馈加抗积分饱和的状态反馈控制算法来获得期望的转向轮转角.根据非线性控制理论，通过建立李雅普诺夫函数，证明线控转向控制系统的渐进稳定.最后，通过实车试验证明控制算法能够有效实现转向轮转角的精确跟踪控制.

Abstract:

In this paper， a controller is designed for steerbywire systems to achieve the desired steering angle of front wheel. The controller is designed based on the nonlinear characteristic of the selfaligning moment generated by the tyre cornering forces and uncertainty of system parameters. Besides, the constraint of actuators is taken into account. A feedforward and state feedback controller overcoming integral saturation is designed with conditional integrators to achieve the desired steering angle. Based on the nonlinear control theory, a Lyapunov function is built to prove that the steeringbywire control system is asymptotically stable. In the end, the steering angle tracking algorithms proposed are verified by real vehicle tests.