Adaptive robust disturbance rejection backstepping control of a novel friction electro-hydraulic load simulator

This paper introduces a novel frictional electro-hydraulic load simulator that avoids the problem of force-motion coupling disturbances in traditional electro-hydraulic load simulators. An adaptive robust disturbance rejection backstepping control (ARDRBC) is proposed to address the challenges posed by parameter uncertainty, external disturbances, and unmodeled behavior, thereby enhancing the system's tracking capability. A new adaptive rule has been designed to address the uncertainty of mechanical subsystems through virtual control adjustments. A sliding mode control scheme based on immersion and invariance has been integrated into the practical control design of hydraulic subsystem to address the neglected dynamics. The stability of the entire system was analyzed using the Lyapunov stability. Comparative experiments were conducted to confirm the practicality and robustness of the proposed method.