Nonlinear Output Feedback Control – of a Pneumatic Muscle Actuator System

A Pneumatic Muscle Actuator (PMA) consists of a cylindrical and isotropic flexible rubber tube, and two connection flanges. When the muscle is inflated with compressed air, it widens. A tensile force thereby arises, as well as a contraction movement in the longitudinal direction. Because of their high power/weight ratio, low price and free maintenance, pneumatic muscles are very attractive for the use as actuators in robotics and prosthetics. The main drawback of pneumatic muscles is that their dynamic behaviour is very nonlinear. This thesis shall give an overview on existing modelling and control approaches for PMAs. One suitable model of a pneumatic muscle has to be implemented in Simulink and used to set up a two muscle system acting on a joint. For tracking of the angular position of the joint a nonlinear output feedback controller shall be designed. The controller performance has to be validated by Matlab simulations