JP5836161B2 - Control device and positioning table device - Google Patents

Description

  The present invention relates to a control device that controls an actuator and a positioning table device.

  In the positioning operation, if there is a disturbance such as an excitation force that disturbs the positioning operation inside or outside of the apparatus, the influence cannot be ignored even if the disturbance is fine when aiming for more accurate positioning. In such a situation, even if positioning control is performed by a normal feedback control system, the control amount is determined after a deviation due to the disturbance occurs, so it is essentially difficult to suppress the influence of the disturbance.

  For this reason, there is known an electric motor control device in which means for estimating disturbance is provided in the control device, and positioning is performed with high accuracy by adjusting the control amount so as to suppress the influence of the disturbance. (For example, refer to Patent Document 1).

JP 2009-247098 A

  In the invention described in Patent Document 1, a disturbance that has already occurred is estimated by amplifying a detection signal using a transfer function that selectively amplifies a signal of a specific frequency, and the disturbance is generated using the estimated disturbance signal. A suppression signal is generated that suppresses the influence of. As described above, since the signal including the influence of the disturbance is input and the signal processing is performed to generate the suppression signal, the output delay for the time required for the signal processing is unavoidable in this case as well, and the disturbance is sufficiently Can not be suppressed. Further, since signal components other than disturbances are also amplified, there is a drawback that the estimation accuracy of disturbances cannot be sufficiently increased.

The invention of claim 1 is a control device that controls an actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a drive state of the actuator, A disturbance frequency estimator for estimating the frequency of the disturbance received by the driven object, a disturbance prediction unit for predicting the subsequent disturbance and generating a predicted disturbance signal based on the frequency estimated by the disturbance frequency estimator, and a prediction A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the driven object due to the disturbance, and the actuator is operated based on the detection information and the request of the suppression force instruction unit. The disturbance predicting unit generates a plurality of explanatory variables driven at the frequency estimated by the disturbance frequency estimating unit, and each of the plurality of explanatory variables and the detection information is used to generate each explanatory variable. The coefficient of light variable determining respectively, the predicted disturbance signal generated based on a plurality of explanatory variables and a plurality of coefficients, disturbance prediction unit compares the disturbance signal component contained in the predicted disturbance signal and the detection information, heavy It is characterized by determining a plurality of coefficients using regression analysis.
The invention of claim 2 is a control device that controls an actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator, and the detection information includes A disturbance frequency estimator for estimating the frequency of the disturbance received by the driven object, a disturbance prediction unit for predicting the subsequent disturbance and generating a predicted disturbance signal based on the frequency estimated by the disturbance frequency estimator, and a prediction A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the driven object due to the disturbance, and the actuator is operated based on the detection information and the request of the suppression force instruction unit. The disturbance predicting unit generates a plurality of explanatory variables driven at the frequency estimated by the disturbance frequency estimating unit, and each of the plurality of explanatory variables and the detection information is used to generate each explanatory variable. The coefficient of light variable determining respectively, the predicted disturbance signal generated based on a plurality of explanatory variables and a plurality of coefficients, explanatory variables, a SIN function and COS functions estimated frequency the same period, with a constant 1 It is characterized by being configured.
According to a third aspect of the present invention, in the control device according to the second aspect , the frequency estimation by the disturbance frequency estimation unit and the generation of the predicted disturbance signal by the disturbance prediction unit are repeatedly executed, and the coefficient of the constant 1 is calculated each time the repetition is performed. A detection unit that detects a change amount and a correction unit that corrects the estimated frequency based on the change amount are provided.
The invention of claim 4 is a control device for controlling an actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator, A disturbance frequency estimator for estimating the frequency of the disturbance received by the driven object, a disturbance prediction unit for predicting the subsequent disturbance and generating a predicted disturbance signal based on the frequency estimated by the disturbance frequency estimator, and a prediction A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the driven object due to the disturbance, and the actuator is operated based on the detection information and the request of the suppression force instruction unit. controlling the generation of the predicted disturbance signal by the estimated and the disturbance predictor of the frequency due to the disturbance frequency estimation unit is repeated based on a predetermined condition, The constant condition is a condition as to whether or not the difference between the commanded position based on the command and the position of the drive target based on the detection information is equal to or greater than a predetermined threshold. The difference between the command position and the position of the drive target is equal to or greater than the predetermined threshold. In this case, the frequency estimation by the disturbance frequency estimation unit and the generation of the predicted disturbance signal by the disturbance prediction unit are performed.
The invention of claim 5 is a control device for controlling an actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a drive state of the actuator, A disturbance frequency estimator for estimating the frequency of the disturbance received by the driven object, a disturbance prediction unit for predicting the subsequent disturbance and generating a predicted disturbance signal based on the frequency estimated by the disturbance frequency estimator, and a prediction A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the driven object due to the disturbance, and the actuator is operated based on the detection information and the request of the suppression force instruction unit. controlled, disturbance frequency estimation unit, the frequency of the disturbance experienced by the drive object based on the detection information a plurality of estimated disturbance predictor is estimated by the disturbance frequency estimation unit Wherein the generating a predicted disturbance signal on the basis of a plurality of frequencies which are.
The invention of claim 6 is a control device that controls an actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator, A disturbance frequency estimator for estimating the frequency of the disturbance received by the driven object, a disturbance prediction unit for predicting the subsequent disturbance and generating a predicted disturbance signal based on the frequency estimated by the disturbance frequency estimator, and a prediction A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the driven object due to the disturbance, and the actuator is operated based on the detection information and the request of the suppression force instruction unit. controlled, disturbance frequency estimation unit based on the detection information, the amount of difference between the drive force and the force required velocity change of the driven object generated the actuator, or Calculates a difference amount between the torque required for the speed change of the driving torque between the driven object generated the actuator, and performs estimation of the frequency based on the difference amount.
According to a seventh aspect of the present invention, there is provided a positioning table device according to any one of the first to sixth aspects, a table to be driven and mounted with a work, an actuator for sliding the table, and detection. And an encoder that detects the amount of drive by the actuator.

  According to the present invention, the drive of the actuator can be controlled with high accuracy.

It is a figure which shows the whole structure of a positioning table apparatus. 2 is a diagram illustrating a configuration of a disturbance estimator 10. FIG. 5 is a flowchart for explaining the operation of a disturbance estimator 10; It is a figure which shows the displacement x of a table. It is a figure which shows the time change of the output O1 (N) of the position controller 9. FIG. It is a figure which shows the output of the disturbance estimator 10. It is a figure which shows the displacement x of the table 1 when the estimation precision of the disturbance estimator 10 is bad. It is a figure explaining the modification 1. FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Hereinafter, the control apparatus according to the present embodiment will be described by taking as an example an apparatus that performs positioning by using a servomotor to move a table, that is, a positioning table apparatus that is used in production equipment or the like.

  FIG. 1 is a diagram illustrating an overall configuration of a positioning table device. The table 1 is held by a left guide 2a and a right guide 2b so as to be slidable in the guide longitudinal direction. A driving belt 4 for sliding the table 1 is fixed to the table 1. The drive belt 4 is wound around the drive pulley 3a and the driven pulley 3b. The output shaft of the servo motor 5 is directly connected to the shaft of the drive pulley 3a. When the servo motor 5 applies a rotational force to the drive pulley 3a, the drive belt 4 is driven and the table 1 slides in the guide longitudinal direction.

  The servo amplifier 7 generates a three-phase alternating current for driving the servo motor 5 based on a command from a host controller (not shown) and a signal S 1 from the encoder 6 provided in the servo motor 5. Supply.

  In the input processor 8 provided in the servo amplifier 7, the signal S 1 from the encoder 6 is converted into a physical quantity necessary for controlling the servo motor 5, for example, angular acceleration, angular velocity, rotational angle, etc. of the servo motor 5. The position controller 9 and the disturbance estimator 10 calculate the drive torque of the servo motor 5 using the physical quantity (control signal as drive information) output from the input processor 8. The power converter 11 generates a three-phase AC O3 to be applied to the servo motor 5 based on this driving torque. Other configurations include an accompanying circuit such as a power line system that supplies power to the power converter 11 and a current control system that adjusts the current flowing through the servo motor 5. However, these are described and illustrated. Omitted.

  In FIG. 1, a control system indicated by encoder 6 → input processor 8 → position controller 9 → power converter 11 → servo motor 5 corresponds to a conventional feedback control system. For example, when a positioning operation is performed by the positioning table device, a command (for example, a speed command for the servo motor 5) is input from the host controller to the servo amplifier 7. As described above, the position signal (pulse signal) S <b> 1 detected by the encoder 6 attached to the servo motor 5 is input to the input processor 8 of the servo amplifier 7. The input processor 8 calculates the speed of the servo motor 5 in the current state based on the position signal S1.

  The position controller 9 calculates the torque generated by the servo motor so that both the position and the speed are close to the command value. The command value is input from the host controller. Since the position controller 9 calculates the position control and the speed control independently, when only the speed command is input, the position controller 9 operates as a calculation block for performing the speed control. Therefore, in the example shown in the present embodiment, only the speed command is input and the operation is performed so as to perform the speed control.

  In this embodiment, an example of speed control will be described. However, the present invention is not limited to this, and position control may be performed by inputting a position command, or both controls by inputting both position and speed commands. You can go. In this way, a drive torque that causes the speed of the servo motor 5 to coincide with the command value is calculated as the output O1 of the position controller 9. In a conventional control device that does not include the disturbance estimator 10, the power converter 11 generates a three-phase alternating current O3 based on the output O1 and the motor rotor position signal S2 input from the input processor 8.

  In this embodiment, a disturbance estimator 10 is provided in addition to such a feedback control system. FIG. 2 is a diagram showing the configuration of the disturbance estimator 10, and FIG. 3 is a flowchart for explaining the operation of the disturbance estimator 10. Hereinafter, the configuration and operation of the disturbance estimator 10 will be described with reference to FIGS. The disturbance estimator 10 includes a disturbance frequency estimation unit 10a, a function determination unit 10b, and a disturbance correction signal generation unit 10c. The physical quantity (control signal) input to the disturbance estimator 10 is input to the disturbance frequency estimation unit 10a and the function determination unit 10b.

  Here, examples of the control signal (physical quantity) input to the disturbance estimator 10 include (a) angular acceleration of the servo motor 5 and (b) angular velocity of the servo motor 5 and inertia of the inertial body driven by the servo motor 5. Product of the total value, (c) a value obtained by subtracting the torque generated by the servo motor 5 from the product of the total inertia value of the inertial body driven by the servo motor 5 and the angular acceleration of the servo motor 5, and (d) a torque not shown. A measured value of a value of a sensor (for example, provided in the servomotor 5), (e) a driving force generated by the servomotor 5 calculated by the host controller, and (f) an inertial body driven by the servomotor 5. A value obtained by subtracting a measured value of a torque sensor (not shown) from the product of the total inertia value and the angular acceleration of the servo motor 5 can be used. Which one is used as the control signal depends on the configuration of the apparatus and the required specifications, and may be one that is suitable in consideration of the cost and accuracy of calculation.

  In step S101 in FIG. 3, the disturbance frequency estimation unit 10a uses the control signal obtained from the speed of the servo motor 5 in the current state, the output torque monitor signal S3 of the servo motor 5 output from the power converter 11, and the like. Based on this, the control signal fluctuation frequency f (disturbance component frequency) is obtained. Note that the output torque monitor signal S3 is not necessarily used. By using it, the estimation accuracy can be increased. As a method of obtaining the frequency, fast Fourier transform may be performed, or it may be obtained from a time such as between the peaks of the waveform of the control signal. In the present embodiment, the frequency is obtained from the signal intensity after conversion using fast Fourier transform. Since the fast Fourier transform is an established technique, description of its operation is omitted. The frequency f output from the disturbance frequency estimation unit 10a is multiplied by 2π by the amplifier 10d and converted to an angular velocity ω.

  In step S102, an explanatory variable (waveform) that is driven at the frequency f (angular velocity ω) determined by the disturbance frequency estimation unit 10a is generated. In the present embodiment, sin (ω · t), cos (ω · t) and constant 1 are used as explanatory variables, where ω is the angular velocity and t is the current time. Note that the explanatory variables used in the present embodiment are examples, and may be, for example, a power function of t, an exponential function, a fractional function, or a combination of these, taking into consideration the configuration of the apparatus and the required specifications. A suitable one may be used in consideration of the cost and accuracy of calculation.

  In step S103, the function determination unit 10b determines the coefficient of the explanatory variable from the generated explanatory variable and the input control signal. As a determination method, there are various methods such as regression analysis and T test. Here, the regression calculation to the explanatory variable is performed using the control signal as the objective variable, and the coefficient of each explanatory variable is determined. That is, in determining the coefficients, calculation is performed so that the error of the linear sum of the coefficient times of the objective variable and the explanatory variable is minimized. For example, the calculation is performed by the least square method. In the present embodiment, the coefficient is determined using calculation by multiple regression analysis for this calculation. As the control signal, the control signals such as (a) to (f) described above are used, and those close to the disturbance component included in the signal S1 are used. Therefore, the result of the regression analysis approximates the disturbance signal with high accuracy. Yes.

In step S104, the disturbance correction signal generation unit 10c is applied after the present time (after frequency estimation) using the explanatory variable using the estimated frequency f (angular velocity ω) and the coefficient determined by the function determination unit 10b. A disturbance is predicted and a predicted disturbance signal model is generated. Assuming that the coefficients determined by the function determination unit 10b are A1, A2, and A3, respectively, the predicted disturbance signal model is expressed by the following equation (1).
A1 · sin (ω · t) + A2 · cos (ω · t) + A3 (1)

  When the predicted disturbance signal model is determined in this way, the process proceeds to step S105, and the disturbance correction signal generation unit 10c outputs a disturbance correction signal O2 based on the predicted disturbance signal model. The disturbance correction signal is obtained by inverting the sign of the predicted disturbance signal. That is, in addition to the drive torque based on the command from the host controller, the force (excitation force) caused by the disturbance predicted to be received by the table 1 to be driven is delayed by the disturbance (force to suppress disturbance) to the disturbance. By causing the servo motor 5 to generate without the vibration, the excitation force due to the disturbance is canceled by the disturbance suppression force (correction torque) generated by the servo motor 5.

  The signal S1 from the encoder 6 includes information on the excitation force due to the disturbance. In order to accurately predict the disturbance, a control signal obtained by appropriately converting the excitation force as the servo motor shaft torque is used. If used, the excitation force due to the disturbance can be accurately canceled (suppressed) by the correction torque of the servo motor 5. For example, when the control signals (a) to (f) described above are compared, the signal (c) most accurately represents the disturbance, and this is preferably used as the control signal. If the control signal of (c) is expressed more generally than the motor, the difference between the driving force generated by the actuator and the force required for the speed change of the driving target, or the driving torque generated by the actuator and the driving This is the difference from the torque required for the target speed change.

  Here, the operation of the disturbance estimator 10 shown in FIG. 3 may be executed for each calculation cycle of the servo amplifier 7 or may be performed at a predetermined time interval different from the calculation cycle. Further, as described later, it may be performed when a predetermined condition is satisfied. In particular, for the function determination unit 10b in the disturbance estimator 10, the coefficients A1 to A3 are updated each time this operation is performed, and the updated A1 to A2 are used for the predicted disturbance signal model, thereby the estimator. The cumulative shift due to the error can be reset, and the correction accuracy for disturbance is further improved. Also, the disturbance correction signal generator 10c and the disturbance frequency estimator 10a in the disturbance estimator 10 may be executed every calculation cycle of the servo amplifier 7, or a certain time interval or certain condition is satisfied. In some cases, the operation may be performed.

  The disturbance correction signal O2 output from the disturbance correction signal generator 10c is input to the power converter 11 shown in FIG. The power converter 11 generates a reference value of a three-phase alternating current to be applied to the servomotor 5 from the output O1 from the position controller 9, the disturbance correction signal O2 output from the disturbance estimator 10, and the motor rotor position signal S2. Electric power to be applied to the servo motor 5 is generated by performing power conversion by PWM. As described above, the output O1 in the present embodiment is a command for generating a driving torque that matches the speed of the servo motor 5 with the command value from the host controller. On the other hand, the disturbance correction signal O2 is a command for generating a correction torque that cancels the excitation force caused by the disturbance. As a result, the servo motor 5 generates torque that suppresses the excitation force due to disturbance while following the command of the host controller.

  Torque from the servo motor 5 rotates the drive pulley 3a to move the belt 4 and slide the table 1. When the table motion changes due to a change in the excitation force due to disturbance, the change in the motion appears as a change in the rotational motion of the servo motor 5 from the table 1 through the belt 4 and the drive pulley 3a. The change in the rotational motion is detected by the encoder 6 and input to the servo amplifier 7, and the calculation by the disturbance estimator 10 is performed again to update the angular velocity ω and the coefficients A1 to A3. As a result, a new disturbance correction signal O2 that cancels the changed disturbance is output from the disturbance estimator 10. That is, by repeatedly performing the operation of FIG. 3, it is possible to follow a change in disturbance and to control the table 1 with high accuracy.

  4-6 is a figure explaining the effect of the disturbance estimator 10, and has shown operation | movement at the time of positioning the table 1 in a predetermined position. FIG. 4 shows the displacement x of the table, where the vertical axis is the displacement and the horizontal axis is the time. From 0 sec to 0.2 sec is the case where the control by the servo amplifier 7 is not performed, and from 0.2 sec to 0.4 sec, when only the position control by the position controller 9 is performed, from 0.4 se to 0.6 sec Shows a case where disturbance suppression control using the disturbance estimator 10 is performed in addition to position control.

  In the example shown in FIG. 4, a disturbance oscillating at a constant period is given to the table 1 in a simulated manner, and when there is no control in the section A (0 sec to 0.2 sec), the table displacement is caused by the excitation force due to the disturbance. Is oscillating periodically. The section B (0.2 sec to 0.4 sec) is a section where only position control is performed, and the section C (0.4 sec to 0.6 sec) is a section where position control and the above-described disturbance suppression control are performed. is there. FIG. 5 shows temporal changes in the output O1 (N) of the position controller 9, and FIG. 6 shows the output (disturbance correction signal O2) (N) of the disturbance estimator 10. In section A without control, all outputs are zero.

  When position control is started so that the table position is positioned at the position of displacement = 0 from time 0.2 sec, the position controller 9 outputs a vibration output O1 as shown in FIG. As a result, the displacement of the table 1 from the position = 0 is reduced, but the influence of the disturbance excitation force cannot be suppressed only by the position control, and the table 1 vibrates around the position = 0.

  On the other hand, the disturbance estimator 10 generates a disturbance correction signal O2 as shown in FIG. 6 based on the input control signal, and outputs the disturbance correction signal O2 from time 0.4 sec. When the disturbance correction signal O2 is output, the influence of the disturbance excitation force is canceled, and the displacement x of the table 1 becomes almost zero as shown in the section C of FIG. 4, and the positioning to the target position (x = 0) with high accuracy. Is done. Thus, since the estimation accuracy of the disturbance estimator 10 is high, when the disturbance suppression by the disturbance estimator 10 is started from 0.4 sec, the vibration of the table 1 is suppressed only by the output (disturbance correction signal) O2 of the disturbance estimator 10. It can be seen that the output O1 of the position controller 9 is zero after 04 sec (section C).

  FIG. 7 shows the displacement x of the table 1 when the estimation accuracy of the disturbance estimator 10 is intentionally deteriorated. The control operation in each section A to C is the same as that shown in FIG. In this case, since the estimation accuracy is poor, it is incomplete to suppress the influence of the disturbance only by the disturbance correction signal O2, and the displacement due to the disturbance is included in the input signal S1 of the servo amplifier 7. For this reason, the control to make the deviation (displacement) zero by the control of the position controller 9 works, but the influence of the vibrational disturbance cannot be suppressed only by that. Therefore, as shown in the section C of FIG. 7, the displacement x gradually increases so as to approach the magnitude in the case of only position control.

[Modification 1]
In the example shown in FIGS. 4 and 7, the disturbance estimator 10 performs learning (frequency estimation) only once, and updates the angular velocity ω and coefficients A1 to A3 (updating a model that generates a predicted disturbance signal). Is not done. However, since the simulated disturbance given here is a sinusoidal disturbance with a constant period and no amplitude change, as described above, if the estimation accuracy is high, the displacement x is set to zero as in section C of FIG. Can be suppressed. However, when the estimation accuracy is poor due to a calculation error, or in the case of an actual complicated disturbance, the vibration of the table 1 may not be suppressed.

  Therefore, by repeating the estimation operation shown in FIG. 3 to update the angular velocity ω and the coefficients A1 to A3, even if the estimation accuracy of the disturbance estimator 10 is poor or the disturbance changes, the table It is possible to perform positioning with high accuracy while keeping the displacement x very small. As a method of repeating the estimation operation, as described above, it may be executed every calculation cycle of the servo amplifier 7 or may be performed at a predetermined time interval different from the calculation cycle. In consideration of the case where the displacement x gradually increases as in the section C of FIG. 7, for example, when the magnitude of the displacement x (peak-peak magnitude) is equal to or greater than a predetermined threshold. The estimation operation in FIG. 3 may be performed again.

  Further, as shown in FIG. 8, a Δω calculation unit 10e may be provided to correct the estimated angular velocity ω. When a deviation occurs between the estimated frequency and the disturbance frequency due to an operation error in the disturbance frequency estimation unit 10a, the coefficient A3 of the explanatory variable (constant 1) calculated by the function determination unit 10b changes. . Therefore, the coefficient A3 is input to the Δω calculating unit 10e, and the Δω calculating unit 10e calculates the deviation Δω of the angular velocity ω from the change of the coefficient A3. Here, Δω = (angular velocity ω0 due to disturbance) − (estimated angular velocity ω). The calculated Δω is added to the estimated angular velocity ω, and explanatory variables sin (ω ′ · t) and cos (ω ′ · t) are generated using the addition result ω + Δω = ω ′.

  Alternatively, Δω may be input to the disturbance frequency estimation unit 10a as shown by a two-dot line in FIG. 8 to tune the estimation calculation in the disturbance frequency estimation unit 10a. By doing so, a frequency corresponding to ω + Δω is output from the disturbance frequency estimation unit 10a.

  By calculating Δω from the coefficient A3 thus calculated and correcting the angular velocity ω, the accuracy of the predicted disturbance signal (that is, the disturbance correction signal O2) can be improved. Here, since Δω is based on the calculation error, if Δω is once calculated and the frequency is corrected accordingly, calculation of the predicted disturbance signal is performed using an accurate angular velocity (ω + Δω) thereafter. Is done. Therefore, as long as the calculation error does not change, Δω may be calculated once. When the correction by Δω is performed, the calculation accuracy of the angular velocity is improved. Therefore, the repetition interval of the estimation operation by the disturbance estimator 10 can be extended as compared with the case where the Δω correction is not performed.

  In the case of a configuration in which Δω is added to the calculated angular velocity ω, the Δω calculation unit 10e continues to output Δω once it has been calculated, and adds Δω each time the angular velocity ω is estimated. Is done. If the calculated value of Δω is equal to or greater than the threshold value, addition of Δω or tuning by Δω may be performed.

[Modification 2]
In the embodiment described above, when frequency estimation is performed in the disturbance frequency estimation unit 10a, the highest frequency (angular velocity ω) among the frequency peaks obtained by performing frequency analysis is output. When the number of disturbance sources is one, even if the frequency is determined in this way, the influence of the disturbance can be effectively suppressed as in the case shown in FIG. However, when the disturbance is a complex waveform or there are a plurality of disturbance sources, a plurality of frequency peaks can be obtained by performing frequency analysis, and the peak heights of the second and subsequent peaks cannot be ignored.

Therefore, in the second modification, the disturbance frequency estimation unit 10a determines a plurality of frequencies in descending order of peaks. For example, when two frequencies (angular velocities ω1, ω2) are determined, sin (ω1 · t), cos (ω1 · t), sin (ω2 · t), cos (ω2 · t) and constants are used as explanatory variables. 1 is generated. The function determining unit 10b determines five coefficients A1, A2, A3, B1, and B2 for these explanatory variable units. In this case, the predicted disturbance signal is expressed by the following equation (2).
A1 · sin (ω1 · t) + A2 · cos (ω1 · t)
+ B1 · sin (ω2 · t) + B2 · cos (ω2 · t) + A3 (2)

  A predicted disturbance signal is generated in the same manner when three or more frequencies are estimated. As described above, by estimating a plurality of frequencies from the control signal, it is possible to generate the disturbance correction signal O2 with high accuracy even for a complicated disturbance, and to effectively suppress the vibration of the table 1 due to the disturbance. .

  As described above, the control device according to the present embodiment has a command for controlling the servo motor 5 as an actuator that drives the table 1 to be driven, and the encoder 6 that detects the drive state of the servo motor 5. The present invention is applied to a control device that controls the servo motor 5 based on the detection information (signal S1). The disturbance frequency estimation unit 10a estimates the disturbance frequency received by the table 1 based on the detection information, and the disturbance estimator 10 predicts the subsequent disturbance (after frequency estimation) based on the estimated frequency. Generate a predicted disturbance signal. Based on the predicted disturbance signal, the disturbance correction signal generation unit 10c generates a disturbance correction signal O2 that requests the servo motor 5 to generate a disturbance suppression force that cancels the force received by the table 1 due to the disturbance. Then, the actuator (servo motor 5) is controlled based on the detection information and the disturbance correction signal O2.

  By performing such control, in an actuator control device used for a positioning device or the like, even if there is a disturbance such as an excitation force that disturbs the positioning operation inside or outside the device, positioning is difficult, The influence of disturbance can be suppressed and highly accurate positioning operation can be performed. Note that, based on the detection information (signal S1), the difference between the driving force generated by the actuator and the force required for the speed change of the driving target, or the driving torque generated by the actuator and the speed change of the driving target is required. It is preferable that the amount of difference from the torque is obtained as a control amount, and the disturbance frequency estimation unit 10a estimates the frequency based on the control amount.

  In the above-described embodiment, the positioning operation of the positioning table device has been described as an example. However, the present invention is not limited to the positioning operation, and can be applied to accurate position control and speed control during movement. Further, the present invention is not limited to the configuration in which the table 1 is driven by a belt, but can be applied to a configuration in which the table 1 is slid by a linear motor. Furthermore, the present invention is not limited to the configuration shown in FIG. 1, and can be applied to various forms as long as it is a control device for an actuator that performs a translational movement, a rotational movement, or the like of a drive target.

  In the above-described embodiment, a periodic excitation force is applied from an excitation force source (not shown). However, even if the excitation source is included in the apparatus, it can be applied in the same manner. Can be suppressed. The excitation source included in the apparatus may be, for example, a geometric fluctuation element such as a shake of a mechanism guide or a surface roughness, or an electromagnetic fluctuation element such as a torque pulsation of the servo motor 5. It may be an electric fluctuation element of the inverter part (power converter 11) of the servo amplifier 7, a fluid fluctuation element such as a change in the air gap pressure, or a combination thereof. May be.

  The above description is merely an example, and when interpreting the invention, there is no limitation or restriction on the correspondence between the items described in the above embodiment and the items described in the claims.

  1: table, 2a: left guide, 2b: right guide, 3a: drive pulley, 3b: driven pulley, 4: belt, 5: servo motor, 6: encoder, 7: servo amplifier, 8: input processor, 9: Position controller, 10: disturbance estimator, 10a: disturbance frequency estimation unit, 10b: function determination unit, 10c: disturbance correction signal generation unit, 10e: Δω calculation unit, 11: power converter

Claims (7)

A control device for controlling the actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator,
A disturbance frequency estimation unit for estimating a frequency of disturbance received by the drive target based on the detection information;
Based on the frequency estimated by the disturbance frequency estimation unit, a disturbance prediction unit that predicts the subsequent disturbance and generates a predicted disturbance signal;
A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the drive target due to the disturbance based on the predicted disturbance signal,
Control the actuator based on the detection information and the request of the suppression force instruction unit,
The disturbance prediction unit generates a plurality of explanatory variables driven at the frequency estimated by the disturbance frequency estimation unit, determines a coefficient of each explanatory variable from the plurality of explanatory variables and the detection information, and Generating the predicted disturbance signal based on the explanatory variables and the plurality of coefficients,
The said disturbance prediction part compares the said disturbance signal component with the disturbance signal component contained in the said detection information, and determines the said some coefficient using multiple regression analysis. A control device for controlling the actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator,
A disturbance frequency estimation unit for estimating a frequency of disturbance received by the drive target based on the detection information;
Based on the frequency estimated by the disturbance frequency estimation unit, a disturbance prediction unit that predicts the subsequent disturbance and generates a predicted disturbance signal;
A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the drive target due to the disturbance based on the predicted disturbance signal,
Control the actuator based on the detection information and the request of the suppression force instruction unit,
The disturbance prediction unit generates a plurality of explanatory variables driven at the frequency estimated by the disturbance frequency estimation unit, determines a coefficient of each explanatory variable from the plurality of explanatory variables and the detection information, and Generating the predicted disturbance signal based on the explanatory variables and the plurality of coefficients,
The control device is characterized in that the explanatory variable includes a SIN function and a COS function having the same period as the estimated frequency, and a constant 1. The control device according to claim 2 ,
The frequency estimation by the disturbance frequency estimation unit and the generation of the predicted disturbance signal by the disturbance prediction unit are repeatedly executed,
A detection unit that detects a change amount of the coefficient of the constant 1 each time the repetition is performed;
And a correction unit that corrects the estimated frequency based on the amount of change. A control device for controlling the actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator,
A disturbance frequency estimation unit for estimating a frequency of disturbance received by the drive target based on the detection information;
Based on the frequency estimated by the disturbance frequency estimation unit, a disturbance prediction unit that predicts the subsequent disturbance and generates a predicted disturbance signal;
A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the drive target due to the disturbance based on the predicted disturbance signal,
Control the actuator based on the detection information and the request of the suppression force instruction unit,
The frequency estimation by the disturbance frequency estimation unit and the generation of the predicted disturbance signal by the disturbance prediction unit are repeatedly performed based on a predetermined condition,
The predetermined condition is a condition as to whether or not the difference between the command position based on the command and the position of the drive target based on the detection information is equal to or greater than a predetermined threshold,
When the difference between the command position and the position of the drive target is equal to or greater than a predetermined threshold, the frequency estimation by the disturbance frequency estimation unit and the generation of the predicted disturbance signal by the disturbance prediction unit are performed. Control device. A control device for controlling the actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator,
A disturbance frequency estimation unit for estimating a frequency of disturbance received by the drive target based on the detection information;
Based on the frequency estimated by the disturbance frequency estimation unit, a disturbance prediction unit that predicts the subsequent disturbance and generates a predicted disturbance signal;
A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the drive target due to the disturbance based on the predicted disturbance signal,
Control the actuator based on the detection information and the request of the suppression force instruction unit,
The disturbance frequency estimation unit estimates a plurality of disturbance frequencies received by the drive target based on the detection information,
The said disturbance prediction part produces | generates the said prediction disturbance signal based on the some frequency estimated by the said disturbance frequency estimation part, The control apparatus characterized by the above-mentioned. A control device for controlling the actuator based on a command for controlling an actuator that drives a drive target and detection information of a detection unit that detects a driving state of the actuator,
A disturbance frequency estimation unit for estimating a frequency of disturbance received by the drive target based on the detection information;
Based on the frequency estimated by the disturbance frequency estimation unit, a disturbance prediction unit that predicts the subsequent disturbance and generates a predicted disturbance signal;
A suppression force instruction unit that requests the actuator to generate a disturbance suppression force that cancels out the force received by the drive target due to the disturbance based on the predicted disturbance signal,
Control the actuator based on the detection information and the request of the suppression force instruction unit,
The disturbance frequency estimation unit is configured to, based on the detection information, a difference amount between a driving force generated by the actuator and a force necessary for a speed change of the driving target, or a driving torque generated by the actuator and the driving target. A control device characterized in that a difference amount with respect to a torque required for the speed change is obtained and the frequency is estimated based on the difference amount. A control device according to any one of claims 1 to 6 ;
A table on which the workpiece is mounted,
An actuator for slidingly driving the table;
A positioning table device comprising: an encoder that is the detection unit and detects a driving amount of the actuator.

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