Dynamics behavior analysis of spatial parallel coordinate measuring mechanism with spherical clearance joints

A universal dynamics modeling and analysis method applied for spatial parallel coordinate measuring mechanism (SPCMM) is proposed. The influence of spherical clearance joints on the accuracy of SPCMM cannot be ignored, it is necessary to study the influence of spherical clearance joints on the dynamic response and chaotic characteristics of mechanisms. A dynamic modeling and analysis method considering three spherical clearance joints based on Lagrange multiplier technology is developed, and the position motion model of joint elements and contact force models are established. On this basis, dynamic response and chaotic characteristics of SPCMM under different clearance values and friction coefficients are analyzed, the reliability of dynamics model is verified by comparing the results from Adams and Matlab. This dynamics modeling and analysis method can provide an important reference value for high quality and high precision applications of spatial parallel mechanisms.