Motion principle and simulation analysis of inverted planetary roller screw mechanism

The working principle and driving geometry relationship of an inverted planetary roller screw mechanism were analyzed. According to the kinetics equations, the relationship of the spiral direction and number of thread among the nut, the roller and the screw, was deduced and a standard for choosing basic parameters was offered. Then, a three-dimensional solid model of the planetary roller screw mechanism was established and related dynamic simulation was carried out by using the multi-body dynamics simulation software-ADAMS. The presented analyses method was validated by comparing the simulation results with those by the theoretical formulas. The contact forces between the nut and the roller, and the roller and the screw with different external load were also computed and discussed.