Constrained model predictive force control of an electrohydraulic actuator

An analytical MPC controller was designed for force control of a single–rod electrohydraulic actuator. The controller based on a difference equation uses short control horizon. The constraints on both input and output variables are taken into consideration by the controller. The mechanism of output constraints satisfaction uses output prediction and makes possible to constrain the output values many sampling instants ahead. Thus, it extends capabilities of the analytical MPC controllers to the field reserved so far for much more computationally expensive numerical MPC algorithms. Results of real life experiments illustrate efficiency of the proposed controller. The results also show that the MPC controller has better tracking performance than conventional P and PI controllers. The MPC controller with the constraint handling mechanisms, though relatively simple, offers very good performance. As the design process is detailed, it is possible to relatively easy adapt the proposed approach to other control plants.

Research highlights
► An analytical MPC force controller with constraint handling mechanism is developed for a single-rod electrohydraulic actuator.
► The controller considers the constraints on both input and output variables.
► The controller is relative simple.
► Results of real life experiments illustrate efficiency of the developed controller.
► Results of real life experiments show that the controller has better tracking performance than conventional P and PI controllers.