Design of a Portable Radial Piston Pneumatic Compressor for Wearable Robot System

Recently, research on exoskeleton robots is actively being carried out. The exoskeleton system has the purpose of assisting or amplifying human muscle strength. Such an exoskeleton system is classified into a system composed of a rigid material and a system composed of a flexible material. In the case of electrons, the degree of freedom of the human body is limited and the weight of the system is heavy. On the other hand, when soft actuators are used, the activity is maximized without constraining the human joint degrees of freedom. Typically, there is a soft exosuit at Harvard and can be divided into two cases: pneumatic actuators and wire motors. In the soft suit, the system using pneumatic actuator has a drawback that it must be used near the compressor. In order to overcome this disadvantage, this research developed a compact mobile compressor. The air consumption of the artificial muscles was calculated before the design and the air supply of the compressor to be designed was determined based on this calculation. The developed compressor has several small pistons arranged in a circle so that the performance of a conventional large piston can be outputted without increasing the required torque of the motor. The overall shape was designed through 3D modeling and confirmed its operation. The design of compressor performance was simulated based on energy equation, ideal gas equation, orifice equation, and kinematic equation. The performance of the compressor was verified by comparing the flow rate and pressure test results with simulation results