Supervisor-Based Switching Strategy for Semi-Active Suspension Control

Vehicle suspensions are the main responsible subsystems for vehicle ride quality. There is an intrinsic trade-off between comfort and road holding features on all types of suspensions. To tackle this shortcoming, semi-active suspensions provide controllable damping, i.e. they can change their dissipative behavior according to the required type of response and achieve acceptable levels of comfort and stability based on performance standards. In literature, multiple controllers are proposed for semi-active dampers; however, they fail to comply with passenger comfort and vehicle stability criteria simultaneously. This paper presents an online supervisor model that can switch over multiple controllers based on the dynamics of the vehicle and specific performance indexes. Multiple road roughness are constructed and the supervisor must switch the controllers in order to accomplish the desired performances. In particular, the proposed switching strategy can select among skyhook and groundhook controllers for a magnetorheological damper. Results show a favorable response of the switching strategy and an improvement in driving maneuverability of 33% when compared to a passive suspension system.