A Novel Pre-control Method of Vehicle Dynamics Stability Based on Critical Stable Velocity during Transient Steering Maneuvering

• Published in: Chinese journal of mechanical engineering 2016-05, Vol.29 (3), p.475-485
• Main Authors: Chen, Jie, Song, Jian, Li, Liang, Ran, Xu, Jia, Gang, Wu, Kaihui
• Format: Article
• Language: English
• Subjects: Algorithms; Braking; Coefficient of friction; Computer simulation; Control algorithms; Control stability; Control systems; Control theory; Dynamic stability; Electrical Machines and Networks; Electronics and Microelectronics; Engineering; Engineering Thermodynamics; Fuel consumption; Heat and Mass Transfer; Instrumentation; Lane changing; Lateral stability; Machines; Manufacturing; Mechanical Engineering; Power Electronics; Processes; Roads; Stability analysis; Steering; Stress concentration; Theoretical and Applied Mechanics; Transport Engineering; Velocity; Wheel brakes; Yawing moments; 动力学稳定性; 机动车辆; 横向稳定性; 直接横摆力矩控制; 瞬态; 硬件在环仿真系统; 稳定速度; 预控制
• ISSN: 1000-9345; 2192-8258
• DOI: 10.3901/CJME.2016.0126.014

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.