A direct pose feedback (DPF) control method applied to a DPF controlled machine is provided. The DPF control method includes a pose compensation control in addition to the position feedback control. The pose compensation control includes an initiation step, a reference system step, an actual pose calculation step and a position compensation step. The sum of the primary driving value and the compensation driving value is output to the driver of each of the motors. The advantage of the DPF control method is that the existing real-time position control loop in the controller can remain unchanged, while the pose compensation control is added to eliminate tool pose error resulted from geometric errors in the machine. The DPF controlled machine uses a pose measuring mechanism to measure the actual pose of the tool and to compensate the tool pose error. Hence, the DPF controlled machine is free of geometric errors.

An online geometric/thermal error measurement and compensation system for computer numerically controlled (CNC) machine tools belonging to the technical field of error testing and compensation of CNC machine tools. The online CNC machine tool geometric/thermal error measurement and compensation system includes two parts: the hardware platform and the measurement and compensation software. The hardware platform includes a unidirectional acceleration sensor, a precision integrated circuit (IC) temperature sensor, a multi-channel temperature data collector, and a geometric/thermal error measurement and compensation host. The error measurement and compensation software runs in the geometric/thermal error measurement and compensation host and realizes testing and compensation of geometric and thermal errors in machine tools, which are communicated to the FANUC CNC system.

The invention relates to a machining tool for machining a workpiece, including a main spindle with a driven shank, a tool holder which can be clamped in the shank, a cutting tool which is arranged on the tool holder, a distance sensor for determining a distance of the shank of the main spindle in relation to a reference point, and a control unit which is configured to perform compensation of the tool path during machining of the workpiece based on an elongation and displacement of the shank and an elongation of the tool holder holding the cutting tool, wherein the elongation and displacement of the shank is determined based on the distance determined using the distance sensor, and wherein the elongation of the tool holder holding the cutting tool is determined based on a rotational speed of the shank.

There is provided a wire electrical discharge machine that includes a temperature detection unit, an actual position correction amount calculation unit, a correction amount calculation unit, a correction amount adjustment unit, a position correction amount adjustment unit, and a corrective movement amount calculation unit. The actual position correction amount calculation unit calculates an actual position correction amount for an upper/lower guide section in accordance with reference position coordinates at a reference temperature and with actual position coordinates at a temperature different from the reference temperature. The correction amount calculation unit uses a prepared correction amount arithmetic expression. The correction amount adjustment unit calculates a correction amount adjustment value from the actual position correction amount and the position correction amount.

A thermal displacement correction method is provided, including a first step of setting an initial tool temperature, a second step of estimating a temperature of a tool or a position measurement sensor based on the initial tool temperature and a temperature of a spindle, a third step of estimating an amount of thermal displacement of the tool or the position measurement sensor with a preliminarily set tool thermal displacement estimation formula based on the estimated temperature, and a fourth step of moving a feed shaft of the machine tool based on the estimated amount of thermal displacement to perform a correction. In the second step, the temperature of the spindle is measured, then a tool-mounted portion temperature of the spindle is estimated from the measured temperature.

Provided is a thermal displacement correction device capable of continuing a thermal displacement correction with high accuracy even when some of a plurality of sensors fail. The thermal displacement correction device includes a sensor information acquisition unit that acquires machine tool temperatures detected by the sensor and a state of the sensors, a thermal displacement estimating method storage unit that stores a plurality of thermal displacement estimating methods, a thermal displacement estimating method selection unit that selects a thermal displacement estimating method to be used for estimating the thermal displacement amount of the machine tool based on the state of the sensors, and a thermal displacement estimating unit that estimates the thermal displacement amount of the machine tool based on the machine tool temperature according to the thermal displacement estimating method selected by the thermal displacement estimating method selection unit.

Provided is a thermal displacement correction method using a machine learning method but making it possible to, on a user side, calculate a thermal displacement amount appropriate to a machine tool of the user and correct the thermal displacement. In a machine tool on a target user side, a thermal displacement amount between workpiece and tool corresponding to a temperature at a preset measurement point is calculated based on a parameter defining a relation between the temperature and the thermal displacement amount, and a positioning position for workpiece and tool is corrected in accordance with the calculated thermal displacement amount. On a manufacturer side, operational status information of the machine tool on the target user side is obtained, an operational status identical to the obtained operational status on the target user side is reproduced with a machine tool of a same type as the machine tool on the target user side based on the obtained operational status information, a temperature at a measurement point identical to the measurement point on the machine tool on the target user side and a thermal displacement amount between workpiece and tool are measured during reproduction, and the parameter is calculated by machine learning based on the measured temperature and thermal displacement amount. The parameter in the machine tool on the target user side is updated with the calculated parameter.

The present invention relates to an apparatus and a method of automatically converting thermal displacement compensation parameters of a machine tool, which automatically convert a compensation parameter of a thermal displacement compensation equation of a machine tool so that the compensation parameter is optimized to a current thermal displacement state of the machine tool in real time based on Z-directional or Y-directional displacement data of a tool tip end of a reference tool measured by a tool measuring unit according to an operation state of the machine tool or various kinds of machine tools or thermal displacement data of the machine tool calculated by measuring a processed portion of a processed material, and temperature data measured by a temperature measuring unit, to minimize a processing error according to thermal displacement and improve processing accuracy of the machine tool.

The present invention relates to methods and devices for compensating for a thermally induced change in position on a numerically controlled machine tool, wherein: a characteristic map describing the thermoelastic behaviour of the machine tool is provided to a control system of the machine tool; one or more temperature values are determined by means of one or more temperature sensors on the machine tool; one or more compensation parameters are determined on the control system of the machine tool on the basis of the one or more temperature values determined and of the characteristic map provided; and wherein a temperature-dependent change in position on the machine tool is performed according to the one or more compensation values determined. According to the invention, the characteristic map provided is adjusted or updated by means of a neural network running on a computer.

Provided is a thermal displacement correction method using a machine learning method but making it possible to, on a user side, calculate a thermal displacement amount appropriate to a machine tool of the user and correct the thermal displacement. In a machine tool on a target user side, a thermal displacement amount between workpiece and tool corresponding to a temperature at a preset measurement point is calculated based on a parameter defining a relation between the temperature and the thermal displacement amount, and a positioning position for workpiece and tool is corrected in accordance with the calculated thermal displacement amount. On a manufacturer side, operational status information of the machine tool on the target user side is obtained, an operational status identical to the obtained operational status on the target user side is reproduced with a machine tool of a same type as the machine tool on the target user side based on the obtained operational status information, a temperature at a measurement point identical to the measurement point on the machine tool on the target user side and a thermal displacement amount between workpiece and tool are measured during reproduction, and the parameter is calculated by machine learning based on the measured temperature and thermal displacement amount. The parameter in the machine tool on the target user side is updated with the calculated parameter.