eng Science and Education Publishing Journal of Automation and Control 2372-3041 2016-12-14 4 2 51 55 10.12691/automation-4-2-10 AUTOMATION20164210 article František Trebuňa 1 Michal Kelemen 2 Miroslav P'stor 2 Ivan Virgala ivan.virgala@tuke.sk 2 Department Applied Mechanics and Mechanical Engineering, Faculty of Mechanical Engineering / Technical University of Košice, Košice, Slovakia Department of Mechatronics, Faculty of Mechanical Engineering / Technical University of Košice, Košice, Slovakia The paper deals with describing of air bellow and designing of control system for its trajectory tracking. A lot of research works were done in the past concerning to pneumatic cylinders and their control systems based on servovalves. This paper investigates unconventional pneumatic actuator - air bellow, which is controlled by two two-way normally closed valves in consideration of expensive servovalves. In the paper air bellow is described as mass-damper-spring mechanical system of 2nd order. The paper also introduces the control system for purposes of trajectory tracking of air bellow top platform. Derived algorithm was experimentally tested on measuring stand while control system consists of PLC B&R X20 in collaboration with input / output measuring card MF634 working through the software Matlab / Simulink. The results show that used methodology is suitable for certain applications, where it is not necessary to achieve high precise of positioning and also there is requirement to stiffness of mechanical system. http://pubs.sciepub.com/automation/4/2/10/automation-4-2-10.pdf air bellow controller PLC pneumatic system stiffness trajectory tracking