Machining of workpieces with model-supported error compensation

A control program for a control device of a machine tool having a tool for machining a workpiece, the control device having a position controller and a model of a position-controlled axis, wherein the control program is stored on a non-transitory storage medium and comprises machine code which when read into a memory of the control device and executed by the control device, causes the control device to operate the machine tool by:

• the position controller sequentially receiving, from a sequence of position setpoint values, a respective position setpoint value, a respective position actual value measured on an output side of the position-controlled axis by a measuring device, and a respective compensation value,
• the control device sequentially reading from a storage device, in which a sequence of successive control errors is stored, control errors commensurate with the sequence of the position setpoint values,
• the control device supplying the read-out control errors to the model of the position-controlled axis,
• the model determining the respective compensation value by simulating a mechanical dynamic behavior of the position-controlled axis based on the respective read-out control error,
• supplying the determined respective compensation value to the position controller,
• determining a resulting value by adding the respective position setpoint value and the respective compensation value and by subtracting the respective actual position value, and
• determining, based on the resulting value, an actuating signal for the position-controlled axis and outputting the actuating signal to the position-controlled axis, wherein the actuating signal sets the position-controlled axis in accordance with the respective position setpoint value, thereby varying a position or orientation, or both, of the tool relative to the workpiece.

A machine tool for machining a workpiece with a tool of the machine tool, wherein the machine tool has a plurality of position-controlled axes moving the tool relative to the workpiece, the machine tool comprising:

• a control device having a position controller and a model of a position-controlled axis, said control device controlling the position-controlled axes of the machine tool by:
• the position controller sequentially receiving, from a sequence of position setpoint values, a respective position setpoint value, a respective position actual value measured on an output side of the position-controlled axis by a measuring device, and a respective compensation value,
• the control device sequentially reading from a storage device, in which a sequence of successive control errors is stored, control errors commensurate with the sequence of the position setpoint values,
• the control device supplying the read-out control errors to the model of the position-controlled axis,
• the model determining the respective compensation value by simulating a mechanical dynamic behavior of the position-controlled axis based on the respective read-out control error,
• supplying the determined respective compensation value to the position controller,
• determining a resulting value by adding the respective position setpoint value and the respective compensation value and by subtracting the respective actual position value, and
• determining, based on the resulting value, an actuating signal for the position-controlled axis and outputting the actuating signal to the position-controlled axis, wherein the actuating signal sets the position-controlled axis in accordance with the respective position setpoint value, thereby varying a position or orientation, or both, of the tool relative to the workpiece.