Analysis of electro-active polymer bending: A component in a low cost ultrathin scanning endoscope

The development of a low-cost active tip bending system for a scanning fiber endoscope or catheterscope has been initiated and proof-of-concept fabrication and testing have been conducted. The actuator material chosen for the design is an ionic conductive polymer metal composites (IPMC) type electro-active polymer (EAP). IPMC materials are inexpensive, especially in small sizes required for ultrathin scopes, allowing the possibility of an active-bending mechanism for the single-use endoscope. The charge and the strain distribution across the 200 μm thick membrane are simulated using finite element analysis (FEA). The deformation results from the numerical analysis agree within 8.5% error of the experimental outcome. An IPMC strip actuator made from a Nafion® membrane and a platinum-plating recipe is developed. The generative force of the actuator is measured and demonstrated to be sufficient to lift the rigid tip of the scanning fiber endoscope. Therefore, this IPMC material is a candidate to be used as a low-cost active bending mechanism for the ultrathin scanning fiber endoscopes and future catheterscopes.