Manual and automatic control of an active suspension for high-speed off-road vehicles

The thrust of this research relates to the development of manual and manual-automatic control algorithms for high-speed off-road vehicles. The research commenced with the representation of a suitably complete model of a quarter of a vehicle equipped with passive and active independent suspension systems using bond graph techniques.; Experimental data of an active suspension system provided the required information to tune the analytical vehicle models, including a model of an electromechanical actuator and an automatic controller. The dissertation compares the analytical and simulation results for parameters such as displacement, velocity, acceleration, actuator force and current, and ground force. It demonstrates that analytical models establish good to excellent agreement with the experimental results. To further validate the analytical models of the system components, the models incorporate features to check and confirm complete system energy balance.; Simulations of a structural model of the human controller working in a closed loop with a vehicle equipped with an electromechanical active suspension demonstrate the human's inability to control the system in a continuous compensatory fashion.; The research substantiates that discrete human intervention with the automatic controller working as the inner-loop control system can significantly reduce the vehicle body's absorbed power. It additionally supports that through discrete human interactions with the automatic controller, an off-road vehicle may travel at 40 miles per hour in severe off-road conditions where a passive suspension vehicle's top speed remains below 15 miles per hour.