Research On Anti-backlash Technology Based On Dual-motor Driving System

At the support of the national 863 project --"Seven Axis and Five-linked Turning and Milling Numerical Control Machine Tool of Manufacturing Large Marine Propeller", the theory and technology of anti-backlash with dual-motor driving system has been researched in this paper, for the purpose to eliminate the mechanic clearance and increase the transmission precision of machine tools. The details are as following:1) According to the analyses about the structure feature of the dual-motor driving system, the basic theories has been proposed, including the working principle, process and the common control mode to eliminate transmission error. Through reading a lot of related literatures around the world, present development and their promising future of anti-backlash technologies has been analyzed and summarized based on dual-motor driving system.2) Start with analyzing the basic structure of the dual-motor driving system, the backlash nonlinearity has been studied. Then the mechanical dynamics equations and electrical equations has been synthesized. While the elasticity of the driving axis was taken into account, the kinetic model of the dual-motor driving system has been set up base on PMSM, with transforming the parameters from the side of motor to the side of load.3) The control algorithms to eliminate the backlash has been discussed, while the electrical preload controller, the intelligent PI velocity difference controller and fuzzy-PI position controller has been designed which is to eliminate the backlash in static and dynamic process and guarantee the control precision and response rapidity.4) The SIMULINK model of the whole servo system has been built and the MATLAB optimize control program has been layout. Then the parameters of the equipments have been calculated and the simulation experiment has been carried out. The result of simulation and experiment will give theory consultation for system design and field debug.