Abstract:Spherical joint is a commonly multidegreeoffreedom mechanical hinge which has many advantages such as compact structure, good flexibility, and high carrying capacity. Realization of its multidimensional angular displacement measurement is of great significance in the prediction, feedback, and control of the system motion error. Firstly, the application of spherical joint and its structural characteristics were presented in the paper. Then, the motion description of the spherical joint and needed angles for measurement were analyzed. A review of multidimensional angular displacement measurement method, including structural decoupling detection method, opticalbased detection method and magneticfieldbased detection method, at home and abroad was provided, Finally, the development of research on multidimensional angular displacement measurement method for spherical joint was summarized. The focus and the difficulty of the research were pointed out, and the challenges and the breakthroughs in the key technologies were also stated.