Decoupling Drive Mechanism of a New Type of Electromagnetic Spherical Wrist

doi:10.3901/JME.2024.19.001

Abstract

Abstract: In order to get rid of the drawbacks of the complex mechanical drive type wrist, break through the electromagnetic decoupling and magnetic moment singularity problems of the existing spherical electromagnetic type joint, as to meet the special need on the variable stiffness control performance of the electromagnetic flexible wrist in non-structural special environments, based on rotating magnetic coaxial effect of a magnet rotor in rotational magnetic field, the decoupling drive mechanism of an electromagnetic spherical robot wrist with two DOFs (degree-of-freedoms) and variable stiffness is proposed.In terms of mechanism, the orthogonal kinematic decoupling of the wrist output axis along pitch and yaw axis is realized by the universal follower mechanism with the built-in magnet rotor, and in terms of electromagnetic drive, the orthogonal orientation decoupling of the rotating coaxial magnetic moment is realized by the orientation decoupling of the spatial universal rotating magnetic field along pitch and yaw axis, thus active drive of the spherical wrist with two DOFs is realized by aid of the orthogonal kinematic decoupling and the rotating coaxial magnetic moment decoupling both along pitch and yaw axis.With the accurate modeling of magnetic field and orthogonal magnetic moment decoupling, the control accuracy of the output magnetic moment and stiffness of the wrist is expected to be significantly improved, which lays the foundation for the realization of compliance control by universal electromagnetic linear variable stiffness in non-structural complex environments.

Key words: spherical wrist, rotating magnetic coaxial effect, electromagnetic drive, universal variable stiffness, magnetic moment decoupling

CLC Number:

TP242

ZHANG Yongshun, LIU Gaoren, LIU Zhijun, LIU Zhenhu, DONG Hai. Decoupling Drive Mechanism of a New Type of Electromagnetic Spherical Wrist[J]. Journal of Mechanical Engineering, 2024, 60(19): 1-10.

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