Implementing P-H High Speed Cornering Method on P-PI Servo Controller with Backlash

In this paper, real-time Pythagorean hodograph (P-H) curve CNC interpolators are used for high speed corner machining. There are large contouring errors around sharp corners when low-bandwidth servo controllers (such as P-PI control) are used. Also backlashes can impose additional errors during tracking a corner. In order to decrease the amount of the cornering errors, an improved interpolation method is proposed. The geometric parameters of the over corner P-H curve and the feed rate along the modified tool path are computed by Pattern Search Algorithm in order to reduce the maximum cornering error. The results of simulation, such as the cornering error and the total cornering time, are compared with previously published methods. It has been observed that the developed over-corner PH approach will substantially reduce the amount of cornering error for P-PI servo controller with backlash.

کلیدواژه ها:

P-H curves ، CNC interpolators ، Cornering error ، Backlash