Hybrid electro-pneumatic robotic arm - integration of pneumatic muscle actuator

This paper describes lightweight, strong and precise hybrid robotic arm actuated by a pneumatic muscle actuator (PMA). The arm is precisely actuated by an electric servomotor with bearing reducer drive chain, and in special cases, when extremely high torque/force is needed (e.g. rescue applications, unintentional arm blocking by obstacle, high load elevating, payload ejecting) also with Pneumatic Muscle Actuator. The PMA acts like a highly nonlinear spring with controlled stiffness. Design and control of such a robotic arm is further described.