Control of input delayed pneumatic vibration isolation table using adaptive fuzzy sliding mode

Abstract

PNEUMATIC ISOLATORS ARE PROMISING CANDIDATES FOR INCREASING THE QUALITY OF THE PRECISION INSTRUMENTS. FOR THIS PURPOSE, HOWEVER, HIGHER PERFORMANCE OF SUCH ISOLATORS IS A PREREQUISITE. IN THIS PAPER AN ADAPTIVE FUZZY SLIDING MODE CONTROLLER IS PROPOSED TO IMPROVE THE PERFORMANCE OF A PNEUMATIC ISOLATOR IN THE LOW FREQUENCY RANGE, I.E., WHERE THE PASSIVE TECHNIQUES HAVE OBVIOUS SHORTCOMINGS. THE MAIN IDEA IS TO COMBINE THE ADAPTIVE FUZZY CONTROLLER WITH ADAPTIVE PREDICTOR AS A NEW TIME DELAY CONTROL TECHNIQUE. THE ADAPTIVE FUZZY SLIDING MODE CONTROL AND THE ADAPTIVE FUZZY PREDICTOR HELP TO CIRCUMVENT THE INPUT DELAY AND NONLINEARITIES IN SUCH ISOLATORS. THE MAIN ADVANTAGE OF THE PROPOSED METHOD IS THAT THE CLOSED-LOOP SYS-TEM STABILITY IS GUARANTEED UNDER CERTAIN CONDITIONS. SIMULATION RESULTS ARE COMPARED TO THE RESULTS OF TDC TECHNIQUE TO VERIFY THE EFFECTIVENESS OF THE PROPOSED METHOD.