Regionless Explicit Model Predictive Control of Active Suspension Systems With Preview

Abstract

Latest advances in road profile sensors make the implementation of preemptive suspension control a viable option for production vehicles. From the control side, model predictive control (MPC) in combination with preview is a powerful solution for this application. However, the significant computational load associated with conventional implicit model predictive controllers is one of the limiting factors to the widespread industrial adoption of MPC. As an alternative, this article proposes an explicit model predictive controller (e-MPC) for an active suspension system with preview. The MPC optimization is run offline, and the online controller is reduced to a function evaluation. To overcome the increased memory requirements, the controller uses the recently developed regionless e-MPC approach. The controller is assessed through simulations and experiments on a sport utility vehicle demonstrator with controllable hydraulic suspension actuators. For frequencies <; 4 Hz, the experimental results with the regionless e-MPC without preview show a ~10% reduction of the root-mean-square (RMS) value of the vertical acceleration of the sprung mass with respect to the same vehicle with a skyhook controller. In the same frequency range, the addition of preview improves the heave and pitch acceleration performance by a further 8 to 21%.