STEERING ASSIST TORQUE CONTROL ENHANCING VEHICLE STABILIITY

Abstract

The usage of electronically controlled systems is recently in the trend of increase. Electronically controlled systems for the vehicle are communicated through the network as CAN (Control Area Network) among individual electronic control systems. By sharing sensor and processing signals through the network among individual electronic control systems, Unified Chassis Control (UCC) which control individual electronic control systems at the same time can be possible. This paper presents Unified Chassis Control System of Electronic Stability Control (ESC) System and Electric Power Steering (EPS) System for improving vehicle dynamic stability. Unified Chassis Control improves vehicle stability by steer intervention to assist driver's maneuverability. ESC detects vehicle-stability and driver-maneuvering through the sensor and processing signals and judges whether steer assist torque intervene for improving vehicle stability. If steer intervention is needed to control vehicle, a motor of EPS generates calculated steering assist torque for steer intervention which is transferred through the network. We demonstrated that Unified Chassis Control improves the vehicle stability by several vehicle tests such as braking or accelerating on Split – µ roads and on under-steer or over-steer condition.