FINITE ELEMENT MODELING AND SEMI-ACTIVE CONTROL OF VIBRATIONS IN ROAD VEHICLES.

Control of vibrations in modern, lightweight road vehicle systems has placed increasingly higher demands on the technology required to model and predict dynamic response of a vehicle system accurately. In this paper, a method for modeling vehicles as systems of interconnected rigid and flexible bodies is presented. Finite element and component mode substitution techniques are employed to characterize elastic motions of flexible bodies in terms of a minimal set of modal coordinates. Equations of motion and constraints of coupled system are written in terms of a set of reference and modal coordinates. Semi-active control techniques are used for suppressing vibrations at some desired points, in the class, located away from suspension attachments. Remote measurements of local displacements and velocities at these points are used to implement a corrective control action into suspension dampers of adjustable damping characteristics.