The Study And Design Of Dual-motor Anti-backlash Driving System Of CNC Turntable

With the fast development of equipment manufacturing, the requirement to highspeed and high precision CNC prccessing center is improved continuously. In theCNC machine tools, the performance of CNC turntable directly affects the stabilityand precision of machining center. But the control system structure of large CNCturntable in the presence of many nonlinear elements, such as the multistage gearclearance and friction torque error, and so on. It is difficult to improve controlprecision and smooth motion in CNC turntable due to the various nonlinear elements.Thereby it is very urgent to eliminate CNC turntable transmission nonlinear elementsfor improving its dynamic response characteristic. This paper will establish themathematical model of actual turntable servo drive system, adopt appropriatealgorithms of dual-motor servo driving control, and simulate and analyze for thecontrol system. These work will has vital significance for the development andapplication of the turntable control system. The main research work is as follows:1. Firstly, this paper has summarized the development situation of CNC turntableand generalize the research of dual-motor anti-backlash method and synchronouscontrol strategy.2. Then this paper has introduced three basic models of backlash nonlinearproblems in the driving system, and emphatically analyzes the basic process in theelimination of gear clearance of dual-motor.3. Through the analysis of the meshing principle of CNC turntable drive system,this paper establishes the mathematical model of turntable dual-motor drive systembased on dead zone nonlinear model, and analysis the effect with or withoutbacklash on the mathematical model.4. Then the control algorithm of speed control loop and position control loop inCNC turntable of dual-motor anti-backlash driving system are discussed.5. SIMULINK simulation model of dual-motor control system has constructed.And the practical value of the physical parameter of driving system has input andcarry out step response, sinusoidal response and load disturbance simulation analysisto verify the feasibility of simulation model.6. The physical test platform of dual-motor control system has been constructedand tested.