Development of Magnetic Geared Screw Two-Degree-of-Freedom Motor with Halbach Array

The paper proposes a magnetic geared screw and two-degree-of-freedom (2-DOF) motors based on the magnetic geared screw. As a 2-DOF motor that generates large thrust force, a magnetic screw 2-DOF motor has been proposed. The magnetic screw 2-DOF motor generates torque around an axis and thrust force along the axis. Additionally, it can amplify the thrust force by the magnetic screw structure. However, the torque generated in the magnetic screw 2-DOF motor is lower in comparison with the thrust force. In order to improve the torque density in the magnetic screw 2-DOF motor, the paper designs a magnetic geared screw. It is a magnetic screw into which a magnetic gear is integrated. Therefore, it converts the input torque into large output torque and thrust force. Moreover, the paper applies Halbach array to the magnetic geared screw 2-DOF motor to significantly improve the output torque and thrust force. The paper indicates the effectiveness of the proposed magnetic geared screw 2-DOF motors with analysis results.