Abstract:

A vehicle dynamics control strategy based on integrated-electro-hydraulic brake system (IEHB) was proposed to improve the driving stability of vehicle under extreme conditions. IEHB system actuator and a 15- DoF vehicle nonlinear dynamics physical simulation model were established in advanced modeling environrnent for performing simulation of engineering systems (AMESim). A hierarchical control structure adopted: yaw moment control layer was designed by utilizing linear proportional control and nonlinear compensation control method; The design of braking torque distributing layer and actuating layer ensured tracking quality of the controlled vehicle to output of reference model layer. The results show that the proposed control method can make the plant track the reference model output under extreme conditions rapidly and accurately. Compared with vehicle dynamics stability control system based on conventional electronic stability control system (ESC), the peak tracking error of yaw rate is reduced by 13.6%, and the convergence time is shortened by 1.3 s. The performance of some vital dynamic parameters, including roll angle, sideslip angle and lateral acceleration, are significantly improved. Vehicle driving stability is optimized remarkably. Therefore, this control method can guarantee the vehicle quickly and accurately track the output of reference model under extreme driving condition.

Key words: automotive safety, integrated-electro-hydraulic brake (IEHB) system, physical simulation model, dynamic stability, hierarchical control structure, nonlinear control