A flatness based design for tracking control of pneumatic muscle actuators

Because of their high power/weight ratio pneumatic actuators, especially the so called pneumatic muscles, are very interesting for the use as actuators in robotics. But, in fact the physical model is highly nonlinear, in the following a flatness based position controller for the pneumatic artificial muscles is presented. The considered pneumatic muscle is produced by the manufacturer Festo and possesses a high pulling force to 4000N and a very long lifetime at least to 10 million switching cycles. The control objective is to track the payload along a specified reference path including an active attenuation. Since a model based control approach is pursued, a physical model is presented for an experimental setup. The model is very nonlinear making nonlinear flatness based control desirable. Experimental results are included and demonstrate the efficiency of the control.