Robust Control of Clutch Engagement Process under Non-Stationary Random Cyclic Conditions

Abstract

A robust control method for clutch engagement process is proposed for the engagement quality problem caused by the nonlinearity, external disturbance and parameter uncertainty in the clutch engagement process. Firstly, taking the clutch engagement process in the heavy-duty reverse shifting of a 5-ton loader in V-type working condition as the research object, a multi-objective functional with performance evaluation based on jerk and friction work is established. According to the Pontryagin's maximum principle and terminal constraints, after solving the functional extremum of the parameterized non-stationary random terms in the disturbance matrix, the optimal trajectory of the torque under the time-varying optimal control law and weight combination is obtained. Secondly, through the variable transformation, the time-varying torque optimal trajectory is transformed into the pressure tracking trajectory of the nonlinear clutch hydraulic actuator with parameter perturbation. Finally, the adaptive sliding mode control (ASMC) strategy is adopted to improve the tracking accuracy and robust performance of the system, and the stability of the closed-loop system is analyzed by Lyapunov stability theory. Numerical simulation results show that the proposed method can effectively reduce the jerk and the friction work, achieve the optimal control trajectory tracking within 0.7% error.