Abstract: An adaptive control for a turning machine which adjusts the machining rate to maintain the actual horsepower dissipated at the cutter tip at a constant set point despite changing workpiece and cutter parameters. The machining rate is adjusted by control of the machine drive and tool feed to achieve required SFM and IPR values, respectively, within maximum and minimum SFM and IPR limits. "Speed" and "Axis" override controls are also provided. The rate of adjustment of SFM and IPR to a deviation of the cutter tip horsepower from the set point is inversely proportional to the measured system gain so that the response factor of the control loop is maximized. The commanded machining rate of (SFM) (IPR) product is periodically determined by estimating the actual machining rate and multiplying the estimate by the ratio of the set point to the cutter tip horsepower.

Abstract: An adaptive control for a turning machine which adjusts the machining rate to maintain the actual horsepower dissipated at the cutter tip at a constant set point despite changing workpiece and cutter parameters. The machining rate is adjusted by control of the machine drive and tool feed to achieve required SFM and IPR values, respectively, within maximum and minimum SFM and IPR limits. "Speed" and "Axis" override controls are also provided. The rate of adjustment of SFM and IPR to a deviation of the cutter tip horsepower from the set point is inversely proportional to the measured system gain so that the response factor of the control loop is maximized. The cutter tip horsepower is determined by subtracting the electrical loss, mechanical friction loss, and the net power required for net acceleration of the drive, from the measured electrical power supplied to the drive motor. The cutting efficiency is monitored to perform tool wear, tool breakage, and tool protection functions.