Finite Element Analysis And Experiment Research On Machine Tool Cutting Force Error

CNC machine tool main error sources include Geometric errors, Thermal errors, Servo system errors and so on. In actual CNC machining process, cutting force cause tool, workpiece, tool post and rail deformation, destroy the correct relative position between the cutting tool and workpiece, directly affect the workpiece machining accuracy and surface quality. For difficult-to-machine materials and high-performance hard machining, geometric error produced by cutting force is particularly serious. So finding out the relationship between the cutting force and machine tool geometric error and trying to reduce the impact of cutting force on machining errors are of great significance for ultimately improving the manufacture precision of CNC machine.The paper systematically expounds the composition of the machine tool geometric error, the mechanism of geometric error produced by cutting force, and creates the finite element entity model of machine tool in ANSYS interactive mode on the basis of CA-6140lathe physical dimensions and material parameters. By loading cutting force in all directions on the model, simulation analysis each component separately influence on the deformation of the machine, get the maximum error value changes under the influence of cutting force and stress-strain distribution; designs a experimental measurement program of machine cutting force-geometric error, builds a laser interferometer experiment platform to precisely measure affecting data of tripartite different cutting force to the yaw angle error of the machine, linear displacement errors and pitch angle error; then transform the machine yaw, pitch angle, linear displacement error data under the impact of cutting forces to the X, Y, Z coordinate position of the three directions and use the data after conversion of the neural network training, to establish a neural network prediction model of cutting force geometric errors. Finally, elaborates the basic ideas of neural network modeling and machine cutting force geometric error compensation, theoretically analyzes the fine-tune instruction to build predictive models using neural network method, imports CNC machine tool CNC control system to adjust the trajectory, achieving the possibility of cutting force error compensation.In summary, this paper through the simulation analysis of physical machine, the experimental measurement, data modeling, gets machine tool error sensitive direction and the stress and strain distribution under the influence of cutting force, finds out the general discipline of the tripartite cutting force upward machine tool machining error influence, explores the theory basis of reducing the error of cutting force by combining neural network method prediction model and CNC system, establishes the error prediction model of neural network by using the measurement data. Accuracy verification results of the error prediction model shows that this method can reduce the cutting force error range.