3-DOF Outer Rotor Electromagnetic Spherical Actuator

Abstract

Conventionally, devices with multiple degrees of freedom (DOF) are realized by using many single-DOF actuators. However, this makes the structure larger, heavier, and more complicated. In order to remove these drawbacks, the development of a multi-DOF spherical actuator is necessary. In this paper, we propose a new 3-DOF outer rotor spherical actuator and its control method. The dynamic characteristics were computed by employing a three-dimensional finite element method and the effectiveness was verified through measurements carried out on a prototype.