A nonlinear controller for trajectory tracking of pneumatic cylinders

This work presents a nonlinear control strategy for pneumatic cylinders that uses two three way independent proportional valves to control the position of a pneumatic cylinder. The control algorithm is based on a sliding mode controller that allows efficient and robust trajectory tracking at any speed of the end-effector and a wide variance range for pay loads. The overall performance of the controller has been achieved with a minimum cost regarding sensors; in fact we only use one linear encoder feedback signal for closing the position loop. The performance of this control strategy has been tested on a experimental device.