Using an Electrically Scale Model to Evaluate Control Strategy for Damping of Hydraulically Driven Off-Highway Vehicles

In the current paper the oscillatory nature of non-suspended vehicles is examined with special reference to skid steer vehicles. For this type of application the oscillations represent one of the main difficulties to be overcome in order to increase marching speed. The basic idea of the control strategy is to accelerate the vehicle when it is pitching forward and vice versa with a view to keep the derivative of the pitch angle substantially zero. Physically, the traction system is employed as the controlling system with the developed torque as the manipulated variable. An accelerometer provides the signal related to the controlled variable. The overall control strategy is evaluated by a scale model that is driven by means of two permanent magnet dc-motors, and then applied to a hydraulically driven skid steer loader.