Development of control method for outer-rotor spherical actuator

Abstract

Conventional multi-degree-of-freedom drive systems need many single-degree-of-freedom actuators, but this makes the structure larger and heavier. The development of a spherical actuator should reduce the number of actuators, but the low torque and narrow rotation range are still problems. We developed a 2-degree-of-freedom spherical actuator with an outer rotor that can produce a higher torque and wider rotation angle. In this paper, we propose a control method; we confirmed its usefulness by performing dynamic analysis using the three-dimensional finite element method and by taking measurements with a prototype.