Research On Second-order Notch Filter Vibration Suppression Method Of Ball Screw Feeding System

In the process of intelligent development of machine tools,the requirements for speed,accuracy and stability are constantly improved.In the process of high-speed and high-strength machining,the error caused by vibration,which was neglected in the previous low-speed machining,has become an unavoidable problem in machine tool processing.As the core component of the machine tool feeding system,the ball screw is subjected to the large impact load of the screw due to the structural characteristics of its own slender shaft and the large impact force of the screw,which will inevitably stimulate multi-degree-of-freedom vibration of the screw(mainly axial vibration,bending vibration and torsional vibration).Therefore,it is urgent to carry out relevant research on how to control vibration;since the main function of the lead screw in the feed system is to transmit torque,the bearing force and support are realized by the ball guide rail,so the bending vibration of the lead screw can be ignored,and the effect of force and torque makes the torsional vibration and axial vibration of the lead screw very prominent.The errors caused by torsional vibration will eventually show as axial motion errors through the screw-nut spiral structure,which reduces the processing accuracy.Therefore,based on the existing notch filter vibration suppression method,this paper studies and designs a second-order notch filter vibration suppression method,which improves the torsional vibration of ball screw feed system.Combined with the engineering practice,the first two orders of torsional mode shapes of the lead screw in the feed system are analyzed and solved,which lays a foundation for the subsequent vibration suppression research.The specific contents include: analyzing the vibration source and vibration type of the ball feed system in the X-axis direction,clarifying the importance of vibration control of the screw;establishing the geometric and mathematical model of the ball screw feed system;theoretical analysis of the feed system inherent Frequency and mode shape,using finite element analysis software to solve the screw mode under pre-stress.Construct a joint simulation test platform for the ball screw feed system.The specific contents include: generating the mechanical model of the feed system required for joint simulation;exploring the principle of suppressing vibration of notch filter method,analyzing the performance of the notch filter algorithm;designing the second-order based on the existing suppression of first-order vibration Notch filter suppression algorithm;The model of the notch filtering method is expressed in series;the motion trajectory is programmed,the parameters in the servo drive module are designed and adjusted,and the joint simulation test product platform is built.The comparative test shows that the second-order notch filter can significantly reduce the vibration amplitude of the system,suppress the torsional vibration of the screw and improve the stability of the system.