Backlash Compensation on CNC Machine Tool Based on Semi-Closed Loop Control

Abstract

The positional accuracy and machining precision are mainly affected by backlash for semi-closed loop control CNC machine tool. And compensation for backlash is essential to improving the accuracy of machine tool. A method is developed to reduce contouring error in this paper. A simulated model of backlash and Open CNC system are used to verify compensation algorithm. Computational simulations and experimental results have shown that the contouring error due to backlash can be greatly reduced by using backlash compensation.

Improving the precision of mechatronic robot drives

“…One approach to increasing the precision of tool motion in machine tools and robots is to compensate the influence of free play outside the position control loop by correction of the specifications from the numerical control system [19][20][21]. In that case, how ever, the precision is not significantly increased, espe cially with frequent changes in direction of the object of control.…”

Reformation and Commissioning Research on Closed-Loop Control of Y Axis CNC Milling Machine

“…Photoelectric encoder mounted on the shaft end of the motor can real-timely read motor coaxial rotating speed signal, realtimely monitor motor angular displacement. Without monitoring the drive chain after the motor shaft, loss of precision caused by screw error, thermal deformation and backlash can't be controlled [1][2][3]. At present, in the mid-range or high-end CNC machine tool, the feed axis servo control circuit generally adopts semi-closed loop or closed loop.…”