Modeling and Direction Control of a 2 D.O.F. Heavy Launching Bed on a Moving Car Using a Full Suspension Model Available to Purchase

In this paper dynamic modeling and direction control of a launching bed (L.B.) with 2 D.O.F. rotation around vertical and lateral axes, mounted on a vehicle moving on a rough road is investigated. The purpose of direction control is to bring the L.B. from any initial angle to a desired angle with respect to the reference frame and to keep it there. The vehicle model is a full car with bounce, yaw, roll and pitch degrees of freedom. The suspension system of the vehicle is considered to have passive elements and unsprung masses. The stiffness of the tires is also included in the model. To control the position of the launching bed, a servo-hydraulic system comprising of hydro-motors, gearboxes, control servo-valves and a pressure compensated pump is employed. The dynamic equations of vehicle, L.B. and actuating control system are derived using Bond Graph method. The system was then detail designed for a utility vehicle with a heavy launching tower. The performance of the control system was evaluated for rough road conditions using computer simulation.