Closed-loop control of spherical actuator based on voltage model

This paper presents a three degree-of-freedom (DOF) permanent magnet spherical actuator, with precise orientation measurement system. Motion control of spherical actuator has been a challenging problem so far. Current-torque control method is the most available control method for permanent magnet spherical actuator, but the control system of this method is quite complex and costly. In this paper we propose a closed-loop control method based on voltage model. This control method not only possesses the advantages of the current-torque control method but also owns a simpler and less costly control system. In addition, the back-emf research of permanent magnet spherical actuator is also discussed in this paper.