In order to realize a pneumatic artificial rubber muscle (PARM) with high damping characteristics, we have developed a new actuator combining an ordinary PARM with a rubber bellows that uses a narrow tube as an air throttle. In the present study, in order to experimentally clarify the dynamic characteristics of the newly developed high-damping PARM, two such PARMs driven by a spool-type servo valve were connected in parallel to a link that has a rod as an inertial load, constituting the driving system of a single joint. The same experiment was carried out using ordinary PARMs, and the superiority of the newly developed PARM was demonstrated. The characteristics of each component of the high-damping PARM, such as the PARM, the rubber bellows, the narrow tube, and the servo valve, were modeled assuming nonlinearity. Then, using MATLAB/Simulink, a nonlinear simulator for the newly developed actuator was developed. The simulation and experimental results indicated that the developed simulator is useful for the design of pneumatic actuators.

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