摘要
The current research of direct yaw moment control（DYC） system focus on the design of target yaw moment and the distribution of wheel brake force. The differential braking intervention can effectively improve the lateral stability of the vehicle, however, the effect of DYC can be improved a step further by applying the control of vehicle longitudinal velocity. In this paper, the relationship between the vehicle longitudinal velocity and lateral stability is studied, and the simulation results show that a decrease of 5 km/h of longitudinal velocity at a particular situation can bring 100° increasing of stable steering upper limit. A critical stable velocity considering the effect of steering and yaw rate measurement is defined to evaluate the risk of losing steer-ability or stability. A novel velocity pre-control method is proposed by using a hierarchical pre-control logic and is integrated with the traditional DYC system. The control algorithm is verified through a hardware in-the-loop simulation system. Double lane change（DLC） test results on both high friction coefficient（μ） and low μ roads show that by using the pre-control method, the steering effort in DLC test can be reduced by 38% and 51% and the peak value of brake pressure control can be reduced by 20% and 12% respectively on high μ and low μ roads, the lateral stability is also improved. This research proposes a novel DYC system with lighter control effort and better control effect.
The current research of direct yaw moment control（DYC） system focus on the design of target yaw moment and the distribution of wheel brake force. The differential braking intervention can effectively improve the lateral stability of the vehicle, however, the effect of DYC can be improved a step further by applying the control of vehicle longitudinal velocity. In this paper, the relationship between the vehicle longitudinal velocity and lateral stability is studied, and the simulation results show that a decrease of 5 km/h of longitudinal velocity at a particular situation can bring 100° increasing of stable steering upper limit. A critical stable velocity considering the effect of steering and yaw rate measurement is defined to evaluate the risk of losing steer-ability or stability. A novel velocity pre-control method is proposed by using a hierarchical pre-control logic and is integrated with the traditional DYC system. The control algorithm is verified through a hardware in-the-loop simulation system. Double lane change（DLC） test results on both high friction coefficient（μ） and low μ roads show that by using the pre-control method, the steering effort in DLC test can be reduced by 38% and 51% and the peak value of brake pressure control can be reduced by 20% and 12% respectively on high μ and low μ roads, the lateral stability is also improved. This research proposes a novel DYC system with lighter control effort and better control effect.
基金
Supported by National Natural Science Foundation of China(Grant Nos.51275557,51422505)
作者简介
CHEN Jie, born in 1987, is currently a PhD candidate at State Key Laboratory of Automotive Safety and Energy, Tsinghua University, China. His research interests include automotive dynamics and control. E-mail： cj 1234cj@sina.comSONG Jian, born in 1957, is currently a professor at Key Laboratory of Automotive Safety and Energy, Tsinghua University, China. His research interests include vehicle dynamics and control.Corresponding author. E-mail： liangl@tsinghua.edu.cnLI Liang, born in 1976, is currently an associate professor at Key Laboratory of A utomotive Safety and Energy, Tsinghua University, China. His research interests include vehicle dynamics and control, advanced chassis electronic control. E-mail： liangl@tsinghua.edu.cnRAN Xu, born in 1986, is currently a doctor candidate at StateKey Laboratory of Automotive Safety and Energy, Tsinghua University, China. His research interests include automotive dynamics and control.JIA Gang, born in 1989, is currently a master candidate at State Key Laboratory of Automotive Safety and Energy, Tsinghua University, China. His research interests include automotive dynamics and control.WU Kaihui, born in 1972, is currently an engineer at Key Laboratory of Automotive Safety and Energy, Tsinghua University China.
