Development of an active micro catheter using a polymer actuator

Basic technologies to realize an active micro catheter using polypyrrole (PPy) as an actuator are being developed. The catheter is composed of a resin tube, a thin metal film for polymerization of PPy, and a PPy deposited on the electrode. From a finite element analysis, it was proved that a silicone tube with a diameter of 0.5 mm and a thickness of 0.05 mm is the best for our specification. Copper film for electropolymerizing PPy, was deposited by RF sputtering on the silicone tube. The copper film was patterned by a laser machining. PPy was polymerized on the copper film, which was deposited on the half side of the silicone tube. When a voltage of 1.5 V was applied to the PPy vs. a titanium electrode in a NaCl solution, the tube bent with a radius of curvature of 12 cm.