Squat and Standing Motion of a Single Robotic Leg Using Pneumatic Artificial Muscles

A simple robotic leg actuated by pneumatic artificial muscles (PAMs) was constructed and analyzed. Many PAM-driven robots used sophisticated design and intelligent controllers to simulate human motion, but they could be costly and inefficient. This paper demonstrated the implementation of a simple proportional-integral-derivative (PID) controller on the robotic leg, and squat and standing motions were chosen as a pre-study of biped locomotion. Spring-muscle antagonism is applied in the mechanism design. To realize continuous motion asymptotic to human, pulse width modulation (PWM) was applied to the solenoid valves which control the inflation and deflation of the PAMs.