Wire-in-hole operation using a magnetic suspension parallel motion hand

This paper deals with wiring tasks in fabrication of micro mechatronics. Insertion of a flexible wire into a hole is very difficult, because the wire will bear large resistance force duping the insertion, which gets the wire to deform. Conventional methods move robot end effector to follow the wire deformation. However it is difficult to detect a small deformation by vision, especially in case of uncertain-shape object. Also in some cases vision cannot be used. So we proposed a method to use only force information while insertion process. The proposed method was implemented to our parallel motion mechanism. The system consists of two finger rods, each of which has three degrees of freedom and magnetic actuators and sensors are attached directly to the finger links. The actuator consists of an air-core coil and a permanent magnet. This design makes the control easy due to X-Y-Z decoupled motion.