Fuzzy PD+I learning control for a pneumatic muscle

A fuzzy learning control technique is used for position tracking involving the vertical movement of a mass attached to a pneumatic muscle. Because the pneumatic muscle is nonlinear and time varying, conventional fixed controllers are less effective than the fuzzy controller proposed in this paper. The controller is of a PID type, with an adaptive fuzzy PD part and a nonfuzzy integral branch. A novelty of the controller is that the fuzzy inverse model, which dynamically adjusts the PD part of the controller, incorporates the internal PM pressure as an input. Experimental results are presented from the pneumatic muscle test facility in the Human Effectiveness Laboratory at Wright-Patterson Air Force Base.