title: Analysis and decoupling control of a permanent magnet spherical actuator.
abstract: This paper presents the analysis and decoupling control of a spherical actuator, which is capable of performing three degree-of-freedom motion in one joint. The proposed actuator consists of a rotor with multiple PM (Permanent Magnet) poles in a circle and a stator with circumferential coils in three layers. Based on this actuator design, a decoupling control approach is developed. Unlike existing control methods that each coil is responsible for both the spinning and tilting motion, the proposed control strategy specifies the function of each coil. Specifically, the spinning motion is governed by the middle layer coils with a step control approach; while the tilting motion is regulated by upper and lower coils with a computed torque control method. Experiments have been conducted on the prototype to verify the validity of the design procedure, and the experimental results demonstrate the effectiveness of the analysis and control strategy.
authors.affiliation: School of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, China.
authors.forename: Weihai
authors.initials: W
authors.lastname: Chen
authors.affiliation: School of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, China.
authors.forename: Jingmeng
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, China.
authors.forename: Xingming
authors.initials: X
authors.lastname: Wu