Effects of servo system on limited cutting width in CNC heavy cutting

摘要

A mathematical model of the computer numerical control (CNC) heavy cutting servo system including chatter in cutting courses was constructed for the chatter in CNC heavy cutting. The theoretical analysis, computer simulation and orthogonal tests on this model show that increasing the gain of position K_(pp) can improve the rapid tracking performance of machine tools, and decreasing the delay time of speed loop τ_s can quickly eliminate the static error in the system, but the limited cutting width b_(lim) will descend correspondingly; excessively large or excessively small gain of speed loop K_(ps) can result in decreasing b_(lim); optimizing K_(pp), τ_s and K_(ps) can improve the dynamic and static performance of the system and increase b_(lim). It is easy and feasible to optimize the servo parameters by the orthogonal test. This method can effectively improve the system's stability and limited cutting width and it is suitable for the CNC heavy cutting of heavy-duty machine tools.