Research On Federate Scheduling Method Based On Constant Force Control In Five-axis Flank Milling Process

With the rapid development of the manufacturing industry,people have put forward new requirements for manufacturing technology.Aerospace parts have complex shapes,extremely high quality requirements and high material removal rates.Therefore,the manufacturing level of aviation structural parts reflects the ability of the manufacturing industry in many countries.The five-axis machine tool is the foundation for manufacturing aviation parts,but the current unreasonable machining parameters have led to low machining quality and long machining time.Taking the S-shaped test piece as the research object,this article does further research on the instantaneous cutter workpiece engagement,cutting force prediction model,and feedrate scheduling method,which is to improve the machining quality and efficiency of five-axis machine tools.The main content is divided into three parts,which are showed as follows:A new method for calculating the instantaneous cutter workpiece engagement is proposed.The geometric relationship between the instantaneous cutter and the machined surface machined is constructed by comprehensively using geometric methods such as curve offset and space vector synthesis.At the same time,the selected test piece is calculated.Reasonable machined parameters are set to calculate the coordinates of instantaneous cutter workpiece contact point and instantaneous entry angle at any time.The method in this paper is compared with the existing calculation methods and the advantages of the developed method is evaluated.This provides parameter support for the next step to calculate the cutting force modelA cutting force model for five-axis flank milling based on the discrete method was established.The instantaneous undeformed chip thickness in the cutting force model is analyzed with cutter runout and tool path taken into consideration.According to the proposed method of instantaneous undeformed chip thickness,the simulation results from matlab are compared with existing methods.Then,the cutting force is simulated by substituting the instantaneous undeformed chip thickness result into the cutting force calculation model.Design the experiment and select the same machining parameters.Use a Kistler dynamometer to measure the cutting force in the workpiece coordinate system.The simulation and experimental values are compared to verify the accuracy of the proposed method.The results show that the method proposed in this paper can predict the cutting force of five-axis flank milling more effectively,which provides a theoretical basis for federate scheduling of five-axis flank milling in the next step.A new federate scheduling method based on constant force control is proposed.First,a fitting instantaneous undeformed chip thickness is proposed and compared with the simulation results in the second part to verify its accuracy.Then the fitted instantaneous undeformed chip thickness is substituted into the cutting force calculation model and the explicit expressions of the feedrate with the peak cutting force and the feed per tooth as variable.In the verification experiment,the instantaneous contact point between the cutter and the workpiece is calculated according to the method proposed in the first part,and then the entry angle of each cutter point is calculated.Then,select a predetermined cutting force and an appropriate feed per tooth.By substituting the parameters of entry Angle,a given peak cutting force and feed per tooth into the explicit expression of feed speed,the scheduled feedrate of each cutter point can be obtained.The accuracy of the proposed method was verified by cutting force experiments.Taylor surface profiler was used to measure the surface roughness before and after optimization,and the result shows that the optimized surface quality was improved.At the same time,the method provides theoretical support for improving the efficiency of five-axis flank milling.