Multiarticular actuator composed of serially connected micropistons for wearable actuator

Pneumatic microactuators such as balloon actuator and piston-cylinder actuator are highly esteemed by their high force densities. This paper proposes serially connected miniaturized micropistons with the aim of both force accumulation and multiarticular structure. Proposed flexible link of micropistons is designed to overcome the drawback of rigid wire-driven mechanism widely used for endoscope. Segmentaized multiarticular structure is flexible so as to be worn around the body of endoscope. Proposed design allows equipping pistons at the head of the body as local actuators. Local actuators can minimize transmission loss. Serially connected miniaturized pistons (22 mm × 10 mm × 0.9 mm) fabricated by electro discharge machining could successfully accumulate individual force (typically 15 mN at 500 kPa). A micropiston fabricated by Si-micromachining was also designed and demonstrated for further flexible structure.