Milling Force Modeling And Compensation Research Based On The Fourier Series

NC milling is now a important equipment in machinery manufacturing.Its directions of development are high precision and efficiency with low cost.NC milling programming are only edited from the geometry informationinstead of the physical state, so milling conditions must be conservative forsafety which restricts the tool’s performance and even affects the quality ofwork piece and the efficiency．In this Paper, a Fourier milling force model isbuilt up to describe the physical state of NC milling．And then the millingforce model is used for milling deformation compensation. The principaltasks are as follows：End milling and ball-end milling are analyzed considering geometricfeatures of milling tool and work piece．By taking the shearing mechanismand the plowing mechanism into account, a Micro-cutter force model is set up.Then total milling force model is integrated within the region in contact．Thenthe model is established through Fourier transform which turn the millingforce into the form of Fourier series.Linear equations for cutting coefficients of milling are made up whenusing slot milling experiments. Cutting experiments are done on a NC millingtool with a milling dynamometer，and cutting coefficients are regressed by meexperimental data. The modeled milling forces and the measured forces are in good agreement．So that the milling force model is verified．A side milling experiment on a thin-plate work pieces is carried out.Based on the milling force model established in this paper, the milling forceof three directions are calculated with those tool geometric parameters andmachining parameters. According to the geometric characteristics andmaterial characteristics, the theoretical milling force deformation can beobtained. With the help of these deformations, tool path optimization iscarried out aimed at compensation of the deformation caused by milling force.Through the contrast of machining error measured in experiments with andwithout compensation, the deformation compensation is proofed to beeffective. Therefore, the model of milling force’s practical value isdemonstrated.