Abstract
A pneumatic cylinder system has been diffcult in position control due to the nonlinearity of the air, friction on packing seal, and parameter variations. Variable Structure Control (VSC) with a proportion valve has been used to overcome the diffcult. However, VSC with an ON/OFF valve is not extensively investigated so far. Therefore, friction compensation using VSC with an ON/OFF valve is proposed in this research. VSC with an ON/OFF valve is designed based on VSC for the proportional one. The experimental results provided the accuracy with 0.1mm as same as using a proportional valve with chattering reduction. The results imply that the ON/OFF valve controlled by VSC is a possible replacement of proportional valve for conventional pneumatic cylinder control system.
