CONTINUOUS SLIDING MODE CONTROL OF A PNEUMATIC ACTUATOR

Sliding mode control has been promoted ns a means to overcome the nonl inearities associated with pneumatic positioning systems. Previously p ublished performance results have been disappointing with reported acc uracies of only +/-5 mm and poor tracking of the sliding surface. New experimental results demonstrate that a properly designed continuous s liding mode controller ( CSLM) is capable of accuracies accuracies of better than +/-0.2 mm. Further, the CSLM controller is able to maintai n performance when the lend mass is varied by upwards of a factor of 1 0. Direct comparison ro a conventional pro-portional differential pres sure controller provides evidence ti?nt CSLM is indeed more robust tha n comparable controllers Sor this application.