A vehicle lateral velocity and yaw rate control algorithm based on a front and rear independent steering system has been proposed. The authors describe a steering actuator control algorithm and practical aspects involved in implementation of the vehicle lateral velocity and yaw rate controller. An experimental vehicle prepared for the evaluation of the algorithm is introduced. An LQ regulator-based synchronized controller is adopted to control independently actuated right and left steering at the same angle. The vehicle lateral and yaw motion control performance, including the steering actuator control subsystem, is evaluated based on experiments with the vehicle. >

An experimental study on vehicle lateral and yaw motion control

In this study, a new integrated Nonlinear Tracking Control (NTC) is developed that includes the dynamic analysis of the hydraulic braking systems. In the developed algorithm, the desired set points for the slip values are iterated from a nonlinear tire model based on the Magic Formula. Simulations of hard braking and steering maneuvers are conducted using the nonlinear Yaw-plane Four-wheel steering vehicle model with Limited Roll motion (YFLR) incorporating the nonlinear Magic Formula tire model (MF). Similar maneuvers are applied to the same vehicle model that is equipped with the conventional PID controller. Braking and vehicle stability performances are compared for the two implemented control systems to verify the reliability of the proposed control. In this study, Four-wheel Steering Control (4WSC) and Variable Slip-ratio Control (VSC) are also developed along with the NTC in the YFLR model to assess the cornering characteristics of the vehicle during braking and turning. Three controllers are independent but are coupled through the states of the longitudinal and lateral tire forces. Considering the tire friction ellipse, the control systems are designed using model matching control method to impose the vehicle braking performances following a desired dynamic model even during large decelerations or lateral accelerations.

Masato Abe

Papers

A Study on Vehicle Turning Behavior in Acceleration and in Braking