Kinematic Characteristics and Dynamic Analysis of Recirculating Planetary Roller Screw Mechanism

The recirculating planetary roller screw mechanism is a transmission mechanism that is engaged by the screw or nut thread and multiple circular groove rollers. This study theoretically analyzed the working principle and motion relationship of the recirculating planetary roller screw mechanism, and established the 3D model of the recirculating planetary roller screw mechanism. The 3D model was imported into the multi-rigid-body dynamics simulation software ADAMS, and the reasonable connection relationship of virtual prototype was set. The dynamics analysis was carried out and related parameters such as angular speed, velocity, force and torque were extracted. The results show that the simulated value of roller angular speed is 28.28 rad/s, the angular speed of roller is -5.20 rad/s, the nut movement velocity is 1.98 mm/s, and the nut displacement is 2 mm. The above values were compared with their corresponding theoretical values, and the error was found to be less than 5%, thus verified the correctness of the simulation results. The contact force of the roller contacting with the screw and the nut respectively presents sine curve characteristics in the nut threadless area. When the load is 5, 10 and 15 kN, the maximum peak of the collision force between the same roller and convex platform of cam ring under different loads are 113.92, 32.31 and 54.08 N, respectively. Besides, the fluctuation range of the maximum peak of the collision force between different rollers and convex platform of cam ring under the same load is similar to the above values, thus the collision force between the roller and convex platform of cam ring peak value is not affected by the load size. The collision torque between the roller and the carrier increases under higher load; the angular speed of the roller begins to change in the nut threadless area during the operation of the recirculating planetary roller screw mechanism, and the maximum sudden change occurs at the contact between the roller and the convex platform of cam ring. This study has certain reference significance for optimizing the overall performance of the recirculating planetary roller screw mechanism.