Fabrication and basic experiments of pneumatic multi-chamber rubber tube actuator for assisting colonoscope insertion

Colonoscopy is an important medical action to detect disorders like colon cancer. However generally it is difficult to insert a scope into the colon, because the colon is flexible and complex shape. This study aims at development of an actuator which can add propelling ability to a colonoscope. We focused on rubber pneumatic actuators, because advantages of them, for example, high compliance, low cost, water proof, and so on, agree with the required properties of medical devices. In previous paper, we designed a novel rubber actuator consisting multi air chambers by using nonlinear FEM (finite element method). In this research, we fabricated the actuator employing the design; whose cross section is about 5mm × 5mm and length is over 100m, by extrusion molding method successfully. The deformation characteristics of the actuator were clarified by a motion capture system. As a result, elliptic trajectory which leads propelling motion was confirmed. In addition, transportation of a dummy scope was achieved by winding two actuators.