Control of pneumatic artificial muscles with enhanced speed up circuitry

Abstract

The power to weight ratio of the actuators is an important design factor for running robots. Therefore pleated pneumatic artificial muscles are optimal actuators. Obviously the weight of the pressure control valves has to be taken into consideration as well. For this application, standard pressure regulating valves are rather heavy and slow. An intelligent controlled number of fast switching on-off valves was tested as an alternative. Ways to decrease the opening and closing times of the valves are discussed in this paper. The pressure control is used to control the angle of a joint actuated by two antagonistic pneumatic muscles. Results will show that this solution has satisfactory speed and accuracy, and reduces the weight of the pressure control significantly.