Catheter tip forming is processing the tip at the distal end so that catheter can move smoothly through the geometrically complex vascular structure. This thermoforming process has a problem in that the polymer tube adheres to the outer surface of the mold. To resolve this problem, previous researchers have coated the outer surface of the mold with PTFE (Polytetrafluoroethylene), which has a low coefficient of friction. However, due to repeated use, the coating is detached and the polymer tube adheres to the mandrels again, and the mold is frequently replaced. Thus, in this study, three types of metal were electroplated on the surface of the mold in to realize the performance of the PTFE coating. To select the optimal plating material, Cr, Zn, and Ni were selected as candidate groups. Surface energy, adhesion force, and abrasion depth & volume were measured for performance comparison. As a result, Ni, which has similar surface properties to PTFE, and the best durability, was selected as the optimal material. Based on these results, we present Ni-plated mold that can replace PTFE.

Electroadhesion has many advantages over other adhesion methods such as pneumatic, hydraulic, magnet, etc. The applications include electrostatic chucks and grippers. Recently, electroadhesion has been adopted for robots working in limited environments. The electro-adhesive climbing robots can be used for inspection and exploration in a variety of conditions. The electroadhesion robots often have a limited adhesion force. In this paper, we propose a novel pad structure improving the adhesion force. An additional insulating layer prevents the discharge from the high voltage application and increases the adhesion force per unit area. The electroadhesion forces were compared for the different pad materials and electrode structures and were partly confirmed as the theoretical model. The proposed pad was used for a climbing robot wheel. The climbing robot weighs approximately 3 kg and can manage to 3 kg of extra weight on metal walls. Experiments showed a 90-degree gradability for the climbing robot.