Design And Simulation Of Planetary Roller Screw For The Heavy Load Lifting Mechanism

The planetary roller screw has the characteristics of high speed overloading and accuracy controlling, has been widely applied to precision equipment, weapons, aerospace and other fields, it will replace the ball screw as new generation precise straight-line drive mechanism. In this paper, the planetary roller screw has been designed to meet the requirement of heavy load, limited space in the project, and carries on the kinematics analysis and finite element simulation based on the PRS simplified model.First, this paper analyzes the specific requirements of transmission system, and determined the transmission scheme through contrasting several common straight line motions. Calculating the correlation dimensions of the planetary roller screw according to the transmission requirements. Created the 3D models of main parts of the planetary roller screw with SolidWorks, and proposed a method of assembling the planetary roller screw, then the model is assembled correctly.Second, the 3D model of the planetary roller screw was simulated based on ADAMS virtual prototype technology, analyzed the movement of the screw, the roller and the nut from the view of kinematics, then obtained the displacement, velocity, acceleration curve of three components in the X, Y, Z axis. The simulation analysis results consistent with the theoretical results, and they indicate that the PRS's structure is accurate and feasible.Finally, this paper elaborated the theoretical basis of the axial contact deformation of the planetary roller screw, calculated the elastic deformation between contact surfaces of the roller with screw and nut based on Hertz theory. According to the finite element analysis steps of the ANSYS Workbench, established the finite element analysis equivalent model of the planetary roller screw, and defined the material properties, create contacts, meshing and applied loads and constraints, and get the finite element analysis results of the planetary roller screw. The results show that the maximum stress in the range of maximum stress, the roller deformation is equal with theoretical results.Compared with the experimental results and simulation about the load deformation relationship, to verify the reasonableness of the planetary roller screw equivalent finite element model, so as to lay the foundation for the further research of planetary roller screw.