A mixed GPC-H infinity robust cascade position-pressure control strategy for electropneumatic cylinders

Lotfi Chikh (1, 2) , Philippe Poignet (3) , François Pierrot (3) , Cédric Baradat (2)

1 LIRMM - Laboratoire d'Informatique de Robotique et de Microélectronique de Montpellier
2 Fatronik France
3 DEXTER - Robotique médicale et mécanismes parallèles

A robust cascade strategy combining an outer position predictive control loop and an inner H infinity pressure control loop is proposed and tested on an electropneumatic testbed for parallel robotic applications. Two types of cylinders are tested, the standard double acting cylinder and the rodless one. A position/pressure difference (or force) strategy is developed and implemented. As the behavior of the nonlinear cylinders is nonlinear, a feedback linearization strategy is adopted. A Generalized Predictive Controller (GPC) is synthesized for the position outer loop and a constrained LMI based H infinity controller is synthesized for the pressure inner loop. Experimental results show the feasibility of the control strategies and good performances in terms of robustness and dynamic tracking.

Mots clés: GPC; cascade control; pneumatic actuators; modeling; LMI; feedback linearization

Mots clés: robust control

Domaines: Automatique / Robotique

Lotfi Chikh, Philippe Poignet, François Pierrot, Cédric Baradat. A mixed GPC-H infinity robust cascade position-pressure control strategy for electropneumatic cylinders. ICRA: International Conference on Robotics and Automation, May 2010, Anchorage, United States. pp.5147-5154, ⟨10.1109/ROBOT.2010.5509386⟩. ⟨hal-00466773⟩