Advantages of rear steer in LTI and LPV vehicle stability control

Abstract

Abstract-In this paper, the advantages of the rear wheel steer in robust yaw stability control of four wheeled vehicles are shown. A MIMO vehicle dynamic stability controller (VDSC) involving front steer, rear steer and rear braking torques is synthesized. The comparison between a vehicle with and without rear steer is done on avoidance maneuver using both LTI and gain-scheduling LPV controller. Both robust H ∞ controllers are built by the solution of an LMI problem. To better evaluate the influence of the rear steer on the performance time domain indexes are introduced. The simulation results show that active rear steer enhances vehicle handling on a low friction surface.

Vehicle sideslip estimation: A kinematic based approach

“…F determines the strength of the stabilizing effect; it needs to be carefully weighted to make sure it intervenes only when needed. Figure 2 proposes the F scheduling block diagram, where δ is the steering wheel angle and β is the sideslip angle derivative, given by (6).…”

“…Sensors and actuators evolution ( [1,2]) has made possible the use of advanced control techniques acting on vehicle dynamics with the aim of generating suitable yaw moment to avoid dangerous conditions or increase performances. Nowadays electronic stability control (ESC) is a standard technology in almost all commercial passenger cars ( [3,4]), while researchers continue to explore the possibility of using rear axle steering to improve the vehicle stability ( [5,6]). From a control standpoint, besides the problem of defining the control laws, the knowledge/measurement of vehicle states presents a challenge.…”

A cooperative control strategy for yaw rate and sideslip angle control combining torque vectoring with rear wheel steering

“…In order to generate higher tire slip angles (i.e. higher lateral tire forces) some controllers cause higher vehicle sideslip angles, thus, yaw rate control and sideslip control should be considered together when designing a electronic stability controller [21] [22] [2]. In the lateral dynamics control two main aspects have to be considered: the vehicle stability and the maneuverability.…”