Abstract: To reduce harmful mechanical vibrations induced by big errors compensation in high speed numerical control machining, a novel method for error compensation based on look-ahead control technology is proposed. The method follows the steps: Due to the impact of error compensator on position control of interrupt service routine unit, control system architecture composed of hardware framework and corresponding software structure with look-ahead control is constructed. The error compensator is removed from interrupt service routine unit. To obtain velocity used in error compensation, velocity planning algorithm based on look-ahead control is proposed. Error data are classified according to the position relationship between compensation points and interpolation points. According to the classification, combined with velocity planning curve determined by look-ahead control algorithm, error data are distributed linearly into interpolation data at one or more interpolation sample periods in machining, and error compensation is accomplished.

Key words: Error compensation, High speed numerical control cutting machining, Look-ahead control