Investigation on Optimum Design and Semi-Active Control for Hydro-Pneumatic Suspension of a Mining Dump Truck

A novel semi-active valve-controllable hydro-pneumatic suspension system (SAVCHPSS), which integrates the optimum design and actuator control, is taken as a potential solution to coordinating the contradiction between the ride comfort and road friendliness of a mining dump truck. A nonlinear physical model of SAVCHPSS considering the friction element is established for the first time. On this basis, the Grey Wolf Optimizer is employed to attain the optimum parameters of the hydro-pneumatic suspension. Simulation results illustrate that the body acceleration and dynamic tire load of the optimized hydro-pneumatic suspension are decreased by 15.4% and 13.6%, respectively. A two-stage hierarchical control scheme is designed for SAVCHPSS in which the modified skyhook control strategy is selected as the top layer controller for improving the comprehensive performances of SAVCHPSS and the bottom layer controller is the polynomial inverse model of the electric proportional valve for tracking the desired control force. Co-simulation results prove that in comparison with the passive suspension, the body acceleration of SAVCHPSS is significantly improved and the dynamic tire load keeps almost unchanged.