Title :
Accurate position control of a pneumatic actuator using on/off solenoid valves
Author :
Van Varseveld, Robert B. ; Bone, Gary M.
Author_Institution :
Dept. of Mech. Eng., McMaster Univ., Hamilton, Ont., Canada
Abstract :
The development of a fast, accurate and inexpensive position controlled pneumatic actuator that may be applied to a variety of robotic applications is described. A novel PWM valve pulsing algorithm allowed on/off solenoid valves to be used in place of costly servo valves. A linear process model was obtained from experimental data using system identification. A PID controller with added friction compensation and position feedforward was successfully implemented. A worst case steady state accuracy of 0.21 mm was achieved with a rise time of 180 ms for step inputs from 0.11 mm to 64 mm. Following errors to 64 mm s-curve profiles were less than 2.0 mm. The controller was robust to a six fold increase in the system mass. The actuator´s overall performance is comparable to that achieved by other researchers using servo valves
Keywords :
actuators; compensation; control nonlinearities; control system synthesis; discrete systems; feedforward; friction; identification; on-off control; pneumatic control equipment; position control; pulse width modulation; robots; three-term control; transfer functions; valves; PID controller; PWM valve pulsing algorithm; friction compensation; linear process model; on/off solenoid valves; pneumatic actuator; position control; position feedforward; system identification; worst case steady state accuracy; Friction; Pneumatic actuators; Position control; Pulse width modulation; Robots; Servomechanisms; Solenoids; System identification; Three-term control; Valves;
Conference_Titel :
Robotics and Automation, 1997. Proceedings., 1997 IEEE International Conference on
Conference_Location :
Albuquerque, NM
Print_ISBN :
0-7803-3612-7
DOI :
10.1109/ROBOT.1997.614300