JP5460371B2 - Numerical controller - Google Patents

Description

  The present invention relates to a numerical control device that numerically controls a controlled device such as a machine tool, and in particular, corrects a mechanical error with respect to a position command for moving a machine position of a table, a spindle head, or the like included in the controlled device. The present invention relates to a numerical control device.

  In order to correct mechanical errors (straightness error, squareness error, etc.) existing in the machine tool, the correction amount is determined based on the amount of machine error measured in advance, and the correction amount is added to the command value. Thus, the mechanical error is corrected (see, for example, Patent Document 1). This correction is called pitch error correction or pitch error correction.

JP 2009-104317 A JP 2000-172341 A

  When correcting the mechanical error at the time of positioning, the correction can be performed by the above-described conventional technique in which the correction amount is added to the command value. However, when trajectory control is performed, that is, when a command that changes the position from moment to moment is given and control is performed so that the trajectory of the actual machine position follows the trajectory of the commanded position, the response of the servo system Due to the effect of the delay, the position where the correction amount is added deviates from the position where the correction amount is actually added, and the correction amount is added at a timing different from the timing at which correction is originally desired, and the locus of the corrected result is commanded. There was a problem that it did not match the trajectory. This phenomenon is particularly noticeable when the command speed is large or when the response delay of the servo system is large.

  If the machine error is periodic, that is, if the machine error repeats a positive value and a negative value at regular intervals, the correction amount added to the position command is also a periodic amount. When the response delay is large, the phase of the correction amount that actually acts shifts from the phase of the original correction amount. When this phase difference is around 180 degrees (degree), the correction is performed. There was a problem of increasing the mechanical error.

  The present invention has been made in view of the above, and an object of the present invention is to obtain a numerical control device that executes numerical control in which a deviation between a trajectory after mechanical error correction and a commanded trajectory is reduced.

In order to solve the above-described problems and achieve the object, the present invention provides an axis control system that controls a plurality of axes that move a same object in directions orthogonal to each other and exist in a machine. has for each axis, in each of the axis control system, the detector position is a detected value of the machine position by the position detector, a position command inputted from the outside, the error between the machine position and the detector position An error correction amount corresponding to a command position applied to an axis different from the axis controlled by the own axis control system of the plurality of axes input from the outside to be corrected, and the machine position is included in the position command. a numerical controller for performing trajectory control of the object by driving the motor so as to follow, each of the axis control system, from the error correction than the response from the position command to said detector location Up to the detector position. A calculation processing execution unit that performs calculation on the position command and the error correction amount so that the response of the position is corrected, and the position command and error correction amount after calculation by the calculation processing execution unit are added together to obtain a corrected position. An adder that outputs a command, and a servo control unit that operates the motor so that the detector position follows the corrected position command.

  According to the present invention, there is an effect that it is possible to obtain a numerical control device that executes numerical control in which a deviation between a trajectory after mechanical error correction and a commanded trajectory is reduced.

FIG. 1 is a block diagram showing the configuration of the numerical control apparatus according to Embodiment 1 of the present invention. FIG. 2 is a block diagram showing the configuration of the numerical controller when the number of axes is two. FIG. 3 is a diagram for explaining the mechanical error. FIG. 4 is a diagram for explaining the control by the conventional numerical control apparatus when there is a response delay of the servo system. FIG. 5 is a diagram for explaining control by the numerical controller according to Embodiment 1 of the present invention. FIG. 6 is a block diagram showing the configuration of the numerical control apparatus according to the second embodiment of the present invention. FIG. 7 is a block diagram showing the configuration of the numerical control apparatus according to the third embodiment of the present invention. FIG. 8 is a block diagram showing the configuration of the numerical control apparatus according to the fourth embodiment of the present invention.

  Embodiments of a numerical controller according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing the configuration of the numerical control apparatus according to Embodiment 1 of the present invention. As illustrated, the numerical control device 30 is connected to a machine 10 including a motor 5 and a load 6 driven by the motor 5. A position detector 7 for detecting the machine position is attached to the motor 5. The machine position detected by the position detector 7 is referred to as a detector position.

  A position command is input to the numerical controller 30. The numerical control device 30 receives the detector position detected by the position detector 7 included in the machine 10. The numerical control device 30 generates a motor driving torque for driving the motor 5 so that the detector position follows the position commanded by the position command.

  The numerical control device 30 has an axis control system 9. The axis control system 9 receives the position command and the error correction amount, and generates a motor drive torque so that the detector position detected by the position detector 7 follows the input position command. Motor drive torque is applied to the motor 5. The error correction amount is for correcting an error (machine error) between the detector position and the actual machine position (machine position). Detailed description regarding the error correction amount will be described later.

  The axis control system 9 includes a model position command calculation unit 1, a model error correction amount calculation unit 2, an adder 3, and a servo control unit 4. The model position command calculation unit 1 calculates a model position command based on the input position command. Further, the model error correction amount calculation unit 2 calculates a model error correction amount based on the input error correction amount. Response characteristics of the model position command calculation unit 1 and the model error correction amount calculation unit 2 will be described later.

  The adder 3 adds the model position command calculated by the model position command calculation unit 1 and the model error correction amount calculated by the model error correction amount calculation unit 2, and adds the addition result (corrected model position command) to the servo control unit. Output to 4. The servo control unit 4 generates a motor driving torque so that the input corrected model position command and the detector position coincide.

  When there are a plurality of axes in the machine 10, a plurality of axis control systems can be installed in the numerical controller 30 corresponding to each of the plurality of axes. FIG. 2 is a block diagram showing the configuration of the numerical controller 30 when the number of axes is two. The machine 10 includes a first axis composed of a first axis motor 15, a first axis load 16 as a load of the first axis motor 15, and a first axis position detector 17, a second axis motor 25, and a second axis motor 25. And a second axis consisting of a second axis load 26 and a second axis position detector 27. Each of the loads 16 and 26 includes a ball screw and a table driven by the ball screw. The moving directions of the first axis and the second axis are arranged to be orthogonal to each other, and the X coordinate of the machine position is controlled by the first axis, and the Y coordinate of the machine position is controlled by the second axis. On the other hand, the numerical control device 30 has a first axis control system 19 and a second axis control system 29. The configuration of these axis control systems 19 and 29 is the same as that of the axis control system 9 in FIG. The axis control system 19 receives the first axis position command and the first axis error correction amount, receives the first axis detector position from the first axis position detector 17, and supplies it to the first axis motor 15. A single-axis motor driving torque is generated. Further, the axis control system 29 receives the second axis position command and the second axis error correction amount, receives the second axis detector position from the second axis position detector 27, and supplies it to the second axis motor 25. The second shaft motor driving torque is generated.

  Although the position of the machine can be controlled in this way, the position detector 7 is usually attached at a position apart from the position (machine position) to be actually controlled in the machine 10. For example, in the case of the first axis in FIG. 2, the position detector 17 is attached to the first axis motor 15 instead of the table constituting the load 16. Thus, if there is a difference between the machine position and the position where the position detector 17 is attached, even if the numerical controller 30 controls the detector position to follow the position command, the machine position and the position command An error (mechanical error) occurs between the two. Differences between the machine position and the position command include machine straightness error, squareness error, ball screw pitch error, and the like. Ideally, it would be ideal if the machine position could be measured directly and used as the detector position, but in order to measure the machine position directly, special measuring equipment would have to be installed. If the measuring instrument is attached, there is a problem that processing cannot be performed, and the mechanical characteristics enter the closed loop control system, so there is a problem that the control system will oscillate if there is mechanical resonance. Absent.

  Therefore, an error correction parameter is set in advance based on a value obtained by measuring the relationship between the detector position and the machine position using a measuring device, and an error for correcting the error between the machine position and the detector position is set. The correction amount is added to the position command. Since the error correction parameter generally changes depending on the position, the error correction parameter is given as a function or a table regarding the position. The error correction amount is determined by the position command and the error correction parameter. By adding the error correction amount in this way, the detector position becomes a value different from the position command, but the machine position follows the position command, and the machine position can be controlled with high accuracy. Become.

  For the error correction parameter between the detector position and the machine position, use a measuring instrument that can directly measure the machine position, such as a laser length meter or contact displacement meter, when the machine position is determined in advance at a plurality of predetermined positions. Based on the measurement results, the difference between the detector position and the machine position at each position is set as an error correction parameter at each position. When the error correction parameter is set as a table relating to the position, the error correction amount is determined by referring to the error correction parameter corresponding to the current position from the table.

  However, if the error correction amount changes from moment to moment in the movement path during trajectory control, and the movement speed is fast or the response delay of the servo system is large, the detector position follows the error correction amount. Disappear. As a result, there is a problem that the actual locus of the machine position deviates from the commanded locus, and correction as intended cannot be performed. Therefore, in the first embodiment of the present invention, in order to bring the actual machine position trajectory closer to the commanded trajectory, the model position command calculating unit 1 is inserted into the position command, and the model error correction amount calculating unit is added to the error correction amount. 2 and the response characteristic of the model error correction amount calculation unit 2 is set to be higher than the response characteristic of the model position command calculation unit 1, and the response from the error correction amount to the detector position is determined from the position command. The response to the detector position is faster.

  The height of response and the speed of response can be considered by replacing with the height of gain response. That is, the higher the frequency response gain at the same frequency, the higher the response and the faster the response. Accordingly, the gain of the frequency response of the model error correction amount calculation unit 2 is set so that the gain of the frequency response from the error correction amount to the detector position is higher than the gain of the frequency response from the position command to the detector position. It is set to be higher than the frequency response gain of the position command calculation unit 1. Alternatively, the response delay time of the step response can be used as an index of the high responsiveness or the response speed. This is because the response delay time of the step response is defined as the time until the value of the step response reaches a predetermined multiple (for example, 0.5 times) of the target value, and the shorter this time, the faster the response.

  In the first embodiment, the model position command calculation unit 1 and the model error correction amount calculation unit 2 are used in order to remove the components in the high frequency region included in the position command and the error correction amount to make it difficult to excite mechanical vibration and the like. Is a filter having a low-pass characteristic. The input / output characteristics of a general filter can be expressed by a transfer function. Here, the transfer function of the model position command calculation unit 1 is set to Gr (s), and the transfer function of the model error correction amount calculation unit 2 is set to Ge (s) (s is a Laplace operator). The gain of the frequency response is obtained by calculating the absolute value of the transfer function. Therefore, the model position command calculation unit so that the frequency response gain | Ge (jω) | of the model error correction amount calculation unit 2 is higher than the frequency response gain | Gr (jω) | of the model position command calculation unit 1. 1 and the model error correction amount calculation unit 2 may be set. However, j represents an imaginary unit, and ω represents a frequency.

In the case of a filter having a low-pass characteristic, the response of the output to the input can be accelerated by setting the response band high. The response band can be defined as the maximum frequency ω at which the gain of the frequency response is a predetermined value (for example, 0.707) or more. The model position command calculation unit 1 is designed to have a desired response characteristic with respect to the position command. For example, Gr (s) is set as the following equation as a filter having a secondary double root.
Gr (s) = Kr ² / (s ² + 2Kr · s + Kr ² ) (1)
Here, Kr is a gain of the model position response and corresponds to the response band of the model position command calculation unit 1. When Kr is set to a large value, the response band of the transfer function Gr (s) of the model position command calculation unit 1 increases accordingly, and the model position command follows the position command quickly. As a result, the detector position becomes the position. Follow the command quickly.

Similarly, the model error correction amount calculation unit is set to have a transfer function Ge (s) as shown in the following equation.
Ge (s) = Ke ² / (s ² + 2Ke · s + Ke ² ) (2)
Here, Ke is a gain of the model error correction amount response, and corresponds to the response band of the model error correction amount calculation unit 2. When Ke is set large, the response band of the transfer function Ge (s) of the model error correction amount calculation unit 2 increases accordingly, and the model error correction amount quickly follows the error correction amount, and as a result, the detector The position quickly follows the error correction amount.

  Therefore, by setting Ke larger than Kr, the response band of the model error correction amount calculation unit 2 is made higher than the response band of the model position command calculation unit 1, and from the response from the position command to the detector position. Also, the response from the error correction amount to the detector position can be made faster.

  The configuration of the servo control unit 4 is, for example, as disclosed in Patent Document 2, a control system that feeds forward position and speed to a feedback control system having a cascade structure having a speed loop and a current loop inside the position loop. It is good to do.

  Next, effects of the first embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a diagram for explaining the mechanical error. In FIG. 3A, a thick solid line represents a command path. This command path is a path along which the position command moves in the X direction. However, a case is considered in which the actual machine position is also displaced in the Y direction due to a machine error, as indicated by a broken line in FIG. In such a case, if the trajectory at the detector position can be controlled as shown by the thin solid line in the figure, the actual machine position can be matched with the command path. Therefore, the difference between the position on the thin solid line in the drawing and the position on the thick solid line in the drawing, that is, the difference between the detector position and the machine position is input to the numerical controller 30 as an error correction amount. FIG. 3B shows the time change of the position command, and FIG. 3C shows the time change of the error correction amount. While the X-axis position command increases at a constant speed, the Y-axis position command maintains a constant value. Further, while the X-axis error correction amount is always 0, the Y-axis error correction amount changes with time corresponding to the change in the mechanical error amount caused by the movement of the X-axis.

  FIG. 4 is a diagram for explaining the control by the conventional numerical control apparatus when there is a response delay of the servo system. According to the conventional numerical control apparatus, when the response delay of the servo system is large, the corrected servo response path, that is, the locus of the detector position is as shown by a broken line in FIG. That is, as shown in FIG. 4B, since the position command moves at a constant speed, the servo response to the position command follows the position command. However, as shown in FIG. Since it changes every moment, the servo response to the error correction amount changes with a delay with respect to the given error correction amount. As a result, the actual locus of the machine position deviates from the command path.

  FIG. 5 is a diagram for explaining control by the numerical control device 30 according to the first embodiment of the present invention. According to the numerical control device 30, by controlling so that the response from the error correction amount to the detector position is faster than the response from the position command to the detector position, the corrected servo response path is shown in FIG. ) As indicated by a broken line, the actual path of the machine position can follow the command path with high accuracy. That is, it is possible to reduce the deviation between the trajectory after the mechanical error correction and the commanded trajectory. The time change of the servo response to the position command at that time is as shown in FIG. 5B, and the time change of the servo response of the error correction amount is as shown in FIG.

  As described above, according to the first embodiment of the present invention, the actual trajectory quickly follows the error correction amount by setting the response to the error correction amount faster than the response to the position command. It is possible to reduce the deviation between the trajectory after the mechanical error correction caused by the servo response delay and the commanded trajectory. Therefore, the mechanical error can be corrected as intended regardless of the response delay of the servo system and the feed speed. Since the machine error can be corrected as intended, the yield of products processed at the machine position can be improved.

  Also, the model position command calculation unit 1 and the model error correction amount calculation unit 2 are filters having low-pass characteristics, and the response band of the filter of the model error correction amount calculation unit 2 is set to the response of the filter of the model position command calculation unit 1. Since it is made higher than the band, it is possible to reduce the deviation between the trajectory after the mechanical error correction and the commanded trajectory, and to remove the high frequency region component included in the position command and error correction amount. Mechanical vibration and the like can be made difficult to be excited.

Embodiment 2. FIG.
FIG. 6 is a block diagram showing the configuration of the numerical control apparatus according to the second embodiment of the present invention. Here, the same reference numerals are given to the same constituent elements as those in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 6, the numerical controller 40 of the second embodiment includes a shaft drive system 41 having a model position command calculation unit 1, a model error correction amount calculation unit 42, an adder 3, and a servo control unit 4. Yes. The adder 3 adds the model position command calculated by the model position command calculation unit 1 and the model error correction amount calculated by the model error correction amount calculation unit 42 to calculate a corrected model position command.

  Here, the model error correction amount calculation unit 42 functions as a dead time element. The dead time of the model error correction amount calculation unit 42 is set to the same time as the response delay time of the model position command. The response delay time is a delay time in a steady state. The delay time in the steady state is obtained by obtaining the steady delay time of the response to the command when a constant speed input is given to the servo system using the final value theorem of Laplace transform.

  When a filter having a second-order multiple root of the gain Kr is used as the model position command calculation unit 1 as in the first embodiment, the response delay time is the reciprocal 1 / Kr of the gain Kr. Therefore, it is preferable that the model error correction amount calculation unit 42 has a dead time equal to the response delay time 1 / Kr of the model position command. However, when the numerical control device 40 executes the discrete time control, it is generally impossible to set the time exactly equal to the response delay time 1 / Kr of the model position command as the dead time of the model error correction amount calculation unit 42. Therefore, in such a case, it is preferable to set the time closest to the response delay time 1 / Kr of the model position command among integer multiples of the sample period.

  As described above, in the second embodiment of the present invention, the model error correction amount calculation unit 42 is configured to function as a dead time element having a dead time equal to the response delay time of the model position command. Thereby, the gain characteristic of the model error correction amount calculation unit 42 becomes 1, which is faster than the response characteristic of the model position command calculation unit 1, but the response delay time in the steady state of the model error correction amount calculation unit 42 is the model. It becomes equal to the position command calculation unit 1. Therefore, according to the second embodiment of the present invention, when the response delay of the model position command calculation unit 1 is large, it is possible to prevent a situation in which the timing for adding the error correction amount becomes too early. The deviation between the locus after error correction and the commanded locus can be reduced.

  Further, by using the model position command calculation unit 1 as a filter having a low-pass characteristic, it is possible to remove components in a high frequency region included in the position command and make it difficult to excite mechanical vibrations.

Embodiment 3 FIG.
If the error correction amount is a periodic function with respect to time, the phase delay due to the servo response delay can be obtained in advance. Therefore, in the third embodiment, the model error correction amount calculation unit is omitted from the first embodiment, and in the model position command calculation unit, the phase of the position command is delayed by an amount that the phase of the error correction amount is delayed in the servo system. The timing of the servo response to the error correction amount is matched with the timing of the servo response to the position command. FIG. 7 is a block diagram showing the configuration of the numerical control apparatus according to the third embodiment of the present invention. In addition, regarding Embodiment 3, the same code | symbol is attached | subjected to the component same as Embodiment 1, and the detailed description regarding this component is abbreviate | omitted.

  As shown in FIG. 7, the numerical control device 50 according to the third embodiment includes a shaft drive system 51 having a model position command calculation unit 52, an adder 3, and a servo control unit 4. The adder 3 adds the model position command calculated by the model position command calculation unit 52 and the error correction amount input to the numerical controller 50 to calculate a corrected model position command to be supplied to the servo control unit 4.

The model position command calculation unit 52 has characteristics as a phase delay filter. When the transfer function from the error correction amount to the detector position is Ged (s) and the error correction amount changes at the frequency ωe, the phase delay at the frequency ωe of the model position command calculation unit 52 is determined from the error correction amount at the frequency ωe. The phase delay filter Gr (s) of the model position command calculation unit 52 is designed so as to be equal to the phase delay amount ∠Ged (j · ωe) of the transfer function up to the detector position. As the phase delay filter, for example, a first-order low-pass filter represented by the following equation is set.
Gr (s) = 1 / (Tr · s + 1) (3)
Tr is the time constant of the low-pass filter, and the phase delay ∠Gr (j · ωe) at the frequency ωe of the model position command calculation unit is the phase delay amount of the transfer function from the error correction amount to the detector position at the frequency ωe. It is set to be equal to ∠Ged (j · ωe).

  As described above, in the third embodiment, when the error correction amount changes at a predetermined frequency, the error correction amount is not operated, and the model position command calculation unit 52 performs the predetermined frequency from the error correction amount to the detector position. Since the phase lag filter characteristic having the phase lag amount equal to the phase lag amount in FIG. 3 is provided, the deviation between the trajectory after the mechanical error correction and the commanded trajectory can be reduced with a simpler configuration compared to the first embodiment. Can be reduced.

Embodiment 4 FIG.
As described in the third embodiment, if the error correction amount is a periodic function with respect to time, the phase delay due to the servo response delay can be obtained in advance. In the fourth embodiment, the timing of the servo response to the error correction amount and the timing of the servo response to the position command are matched by advancing the phase of the error correction amount without manipulating the phase of the position command. FIG. 8 is a block diagram showing the configuration of the numerical control apparatus according to the fourth embodiment of the present invention. In the fourth embodiment, the same reference numerals are given to the same components as those in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 8, the numerical control device 60 of the fourth embodiment includes a shaft drive system 61 having a model error correction amount calculation unit 62, an adder 3, and a servo control unit 4. The adder 3 adds the position command input to the numerical controller 60 and the model error correction amount calculated by the model error correction amount calculation unit 62 to calculate a corrected model position command to be supplied to the servo control unit 4. .

The model error correction amount calculation unit 62 has characteristics as a phase advance filter. Assuming that the transfer function from the error correction amount to the detector position is Ged (s) and the error correction amount changes at the frequency ωe, the phase advance amount at the frequency ωe of the model error correction amount calculation unit 62 becomes the error correction at the frequency ωe. The phase advance filter Ge (s) of the model error correction amount calculation unit 62 is set so as to be equal to the phase delay amount ∠Ged (j · ωe) of the transfer function from the amount to the detector position. As the phase advance filter of the model error correction amount calculation unit 62, for example, a filter having a primary zero point represented by the following equation is set.
Ge (s) = Te · s + 1 (4)
Te is a time constant of the filter, and the phase advance amount (the value obtained by sign-inversion of the phase delay amount) −∠Ge (j · ωe) at the frequency ωe of the model position command calculation unit is detected from the error correction amount at the frequency ωe. It is set to be equal to the phase delay amount ∠Ged (j · ωe) of the transfer function up to the position.

  As described above, in the fourth embodiment, when the error correction amount changes at a predetermined frequency, the position command is not operated, and the model error correction amount calculation unit 62 performs the predetermined error from the error correction amount to the detector position. Since the phase advance filter characteristic for advancing the phase by an amount equal to the phase lag amount at the frequency is provided, the deviation between the trajectory after the mechanical error correction and the commanded trajectory is simpler than that of the first embodiment. Can be reduced.

  As described above, the numerical control device according to the present invention is useful for a numerical control device that numerically controls a controlled device such as a machine tool. In particular, the position of a machine such as a table or a spindle head included in the controlled device is moved. It is suitable for a numerical control device that corrects a mechanical error with respect to a position command for causing a position command.

DESCRIPTION OF SYMBOLS 1 Model position command calculating part 2 Model error correction amount calculating part 3 Adder 4 Servo control part 5 Motor 6 Load 7 Position detector 9 Axis control system 10 Machine 15 1st axis motor 16 1st axis load 17 1st axis position detection 19 First axis control system 25 Second axis motor 26 Second axis load 27 Second axis position detector 29 Second axis control system 30 Numerical control device 40 Numerical control device 41 Axis drive system 42 Model error correction amount calculation unit 50 Numerical control device 51 Axis drive system 52 Model position command calculation unit 60 Numerical control device 61 Axis drive system 62 Model error correction amount calculation unit

Claims (6)

A plurality of axes that move the same object in directions orthogonal to each other and each having an axis control system that controls a plurality of axes existing in the machine . In each axis control system, a machine that uses a position detector Self-axis control of the plurality of axes input from the outside for correcting an error between the detector position that is a position detection value, a position command input from the outside, and the detector position and the machine position Using the error correction amount corresponding to the command position applied to an axis different from the axis controlled by the system , the trajectory control of the object is performed by driving the motor so that the machine position follows the position command. A numerical controller,
Each axis control system
An arithmetic processing execution unit that performs an operation on the position command and the error correction amount so that a response from the error correction amount to the detector position is faster than a response from the position command to the detector position; ,
An adder for adding the position command and the error correction amount after calculation by the calculation processing execution unit and outputting the corrected position command;
A servo control unit that operates the motor so that the detector position follows the corrected position command;
A numerical control device comprising: The calculation by the calculation processing execution unit is to apply a filter having a low-pass characteristic to the position command and the error correction amount input from the outside,
The numerical control device according to claim 1, wherein a response band of a filter that acts on the error correction amount is higher than a response band of a filter that acts on the position command. The calculation by the calculation processing execution unit causes a predetermined filter having a response delay time to act on the position command input from the outside, and applies an error correction amount input from the outside to the error correction amount of the predetermined filter. It is to execute a process in which a time equal to the response delay time is a dead time.
The numerical controller according to claim 1.   The numerical control apparatus according to claim 3, wherein the predetermined filter is a filter having a low-pass characteristic. The error correction amount input from the outside periodically changes with a predetermined frequency with respect to time,
The calculation performed by the calculation processing execution unit is a position where a phase lag filter having a phase lag amount equal to the phase lag amount at the predetermined frequency from the error correction amount input from the outside to the detector position is input from the outside. To act on the command,
The numerical controller according to claim 1. The error correction amount input from the outside periodically changes with a predetermined frequency with respect to time,
The calculation by the calculation processing execution unit is an error input from the outside by a phase advance filter that advances the phase by an amount equal to the phase delay amount at the predetermined frequency from the error correction amount input from the outside to the detector position. To act on the correction amount,
The numerical controller according to claim 1.

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