Abstract:In order to realize a motion form of three-dimensional rotation and two-dimensional translation in space, a 5-DOF (five degrees of freedom) parallel mechanism with a 3-SPS / PPS configuration is proposed. The driving chain of the mechanism is SPS branch and the constraint chain is PPS branch. Based on the screw theory, the paper analyzes the branch chain of the 3-SPS / PPS parallel mechanism, calculates the degree of freedom of the parallel mechanism, and obtains the expression of the position equation of the parallel mechanism. The model of 3-SPS / PPS parallel mechanism is established by three-dimensional modeling software, and the motion simulation analysis is carried out by using ADAMS software, so that the displacement curve change diagram of 3-SPS / PPS parallel mechanism under inverse solution is obtained, and the displacement, velocity and acceleration motion curve diagram under forward solution is obtained, which verifies the degree of freedom of 3-SPS / PPS parallel mechanism, and provides theoretical reference for the application of parallel mechanism.