No abstract

No abstract

No abstract

An 8-DOF micro hand consisting of two rotational fingers is developed. The fingertips are glass rods. Each finger has 4 DOF: 3-DOF translation of the fingertip driven by three linear stages and 1-DOF rotation about its cylindrical axis by one rotation stage. The fingertip is attached to the rotation stage. The fingers are tilted and placed on an inverted microscope's stage from both sides of the objective lens. The fingertips cross each other and grasp an object above the objective lens. The fingers translate the grasped object spatially by moving in the same direction together. They can rotate the object about its two axes by moving back and forth or rotating about their cylindrical axes. Because of the eccentricity of rotation, the fingertip cannot rotate exactly on its cylindrical axis only by the rotation stage. Moving the three linear stages corrects this position error of the fingertip caused by the eccentricity of rotation. The translation and rotation of a spherical soft object about 100[ m] in diameter are ascertained by experiment.

This report proposes a miniaturized non-contact actuation mechanism for a surgical device for bone extension operation. The device is embedded inside the body, and the device controls the gap between the bones cut by operation. A small permanent magnet is attached to the outer gear of a cycloidal reducer that rotates a screw of the screw-nut mechanism. This magnet is forced by the external magnetic flux density controlled by the outer permanent magnets’ position. In this research, two pairs of permanent magnet bar were rotated by stepping motors outside the device. The outer gear is constrained in As a result, ring gear of the cycloidal reducer is driven in translational wobbling motion the inner gear is connected to the screw and the output nut position is driven linearly with screw rotation. The dimensions of the fabricated device were 7 mm in diameter and 39.7 mm in length. The output thrust of this device was 2 N.