Model Predictive Control of a Hydraulic Multichamber Actuator: A Feasibility Study

This paper presents a model predictive control (MPC) strategy for a hydraulic multichamber actuator. The actuator of interest is a hydraulic cylinder with four cylinder chambers connected to a common pressure rail through a set of hydraulic valves. The control challenge is to achieve accurate force control with preserved energy efficiency at all times. MPC is here used to overcome the difficulties in mode switching, being a multivariate control problem that involves fast pressure dynamics. For this, a simplified internal model is conceived while the energy efficiency aspect is managed by a separate controller, referred to as the force index controller. Simulations reveal how different controller variations affect the tradeoff between energy efficiency and force tracking performance. Due to its relevance to energy efficiency, the study highlights how the switching losses stand in relation to throttle losses.