A Health Aware Control Design for Extending the Remaining Useful Life of an Electro-Hydrostatic Actuator

Abstract

Electro-hydrostatic actuators are widely used in aerospace, industrial, and off-road machinery due to their efficiency and self-contained design. However, gear-pump degradation increases internal leakage, reducing performance and elevating failure risk.This paper proposes a health-aware control framework that accounts for pump degradation in closed-loop control. Internal leakage progression is modeled with a nonlinear Wiener process and the degradation state is estimated online with an extended Kalman filter. The degradation state is used within a nonlinear model predictive controller to adjust control actions using predicted remaining useful life.The approach is evaluated in nonlinear simulations and compared with a proportional–integral–derivative controller. Results indicate that the proposed controller mitigates leakage-induced performance loss and increases predicted pump remaining useful life by 2.75% while maintaining acceptable position tracking accuracy. Although the improvement is modest under accelerated degradation, the framework is suited to slowly evolving degradation and supports predictive maintenance of safety-critical actuation systems.