JP4349275B2 - Method and apparatus for detecting vibration frequency of motion control apparatus - Google Patents

Description

  The present invention relates to a vibration frequency detection method and apparatus for a motion control apparatus that easily detects a resonance frequency and an anti-resonance frequency to be controlled.

The conventional resonance frequency detection device detects the time when the maximum absolute value of the detection signal when the sweep sine wave signal is input, and resonates the frequency of the sweep sine wave signal input at that time. The frequency is detected (for example, refer to Patent Document 1).
Japanese Unexamined Patent Publication No. 2003-134868 (page 5-7, FIG. 1)

FIG. 7 shows a resonance frequency detection device described in Patent Document 1.
In FIG. 7, 51 is a command generator, 52 is a controller, 53 is an electric motor, 54 is a machine, 55 is a detector, and 56 is a signal processor. The command generator 51 outputs a swept sine wave command whose frequency changes from the minimum frequency Fmin to the maximum frequency Fmax as the command signal C, and at the same time outputs the frequency information A of the command signal C that changes every moment. The controller 52 applies the command signal C received from the command generator 51 to one input terminal of an adder provided between the controller 52 and the closed loop controller 57, drives the motor 53 according to the output, and connects The machine 54 is operated. The detector 55 connected to the electric motor 53 detects the electric motor operating amount m and sends it to the signal processor 56 as a response signal S. In this figure, since the motor 53 and the machine 54 are connected, the resonance characteristic of the machine 54 can be detected by detecting the motor operation amount m. The response signal S has a resonance characteristic in which the machine 54 shows a large response depending on the frequency even with a small external force, and therefore has a maximum amplitude at the resonance frequency. The signal processor 56 receives the frequency information A and the response signal S of the swept sine wave command, and performs a calculation for detecting the resonance frequency from the detection minimum lower limit frequency Flim that has passed the minimum frequency Fmin. The frequency of the swept sine wave when the absolute value of the response signal S is at the maximum detection minimum lower limit frequency Flim is determined as the resonance frequency, and the resonance frequency detection result f is output.
According to the vibration frequency detection device described in Patent Document 1, the resonance frequency can be calculated at high speed with a simple calculation, and the resonance frequency is detected using an inexpensive calculation device.

  As described above, in the conventional vibration frequency detection device, a swept sine wave is input, and the frequency of the swept sine wave when the absolute value of the response signal at that time is maximized is determined as the resonance frequency to obtain a resonance frequency detection result. The procedure was taken.

  In the conventional vibration frequency detection method, a swept sine wave is input, the frequency of the swept sine wave when the absolute value of the response signal at that time is maximized is determined as the resonance frequency, and a resonance frequency detection result is taken. Therefore, if the resonance frequency is high and the resonance appears in the response signal, it can be detected well, but if the resonance frequency is low and the resonance does not appear in the response signal, the resonance frequency cannot be detected. . In addition, even if it can be detected, there is a problem that a detection error becomes large.

  Even if the resonance frequency is high and resonance appears noticeably, the resonance frequency of the actual control object changes due to the effect of the closed loop system, but the conventional method controls the changed frequency after being affected by the closed loop system. Since the target resonance frequency is detected, there is a problem that the detection error increases as a result.

  The present invention has been made in view of such problems, and does not detect the maximum of the absolute value of the response signal, but instead determines the frequency of the sweep sine wave when the detection signal becomes the smallest as the control object itself. Resonance frequency is detected by determining the resonance frequency, and at the same time, the frequency of the swept sine wave when the manipulated variable is the smallest after applying the swept sine wave is determined as the resonance frequency of the control object itself, and the resonance frequency is detected. As a result, it provides a method that can accurately estimate the resonance frequency and anti-resonance frequency of the controlled object at the same time in one measurement without being affected by the closed loop system, even when the resonance frequency is low. The purpose is to do.

In order to solve the above problem, the present invention is as follows.
The invention according to claim 1 relates to a vibration frequency detection method for a motion control apparatus, a control object comprising a motor and a machine connected to the motor, a detector for detecting a state quantity of the motor, and the detection value. A closed-loop controller that performs control so that the command to the electric motor and the detected value coincide with each other and outputs an operation amount, a servo amplifier that inputs the operation amount and outputs an electric current for operating the electric motor, and a range to be detected In the vibration frequency detection method for a motion control apparatus, comprising: a sine wave generator that generates and outputs a swept sine wave in a frequency band of: and an adder that adds the swept sine wave to the manipulated variable. The time ta when the detected vibration amplitude of the detected value becomes the minimum is detected, the time tb when the vibration amplitude of the output of the adder becomes the minimum is detected, and the sweep sine wave generator is generated at the time ta Sine wave signal Is the anti-resonance frequency WL to be controlled, and the frequency of the sine wave signal generated by the swept sine wave generator at time tb is the resonance frequency WH to be controlled. The resonance frequency is detected.

  The invention according to claim 2 relates to a vibration frequency detection method for a motion control device, a control object comprising a motor and a machine connected to the motor, a detector for detecting a state quantity of the motor, and the detection value. A closed loop controller that performs control so that the command to the motor and the detected value coincide with each other and outputs an operation amount, a servo amplifier that inputs the operation amount and outputs a current for operating the motor, and a specified designation A vibration frequency detection method for a motion control apparatus, comprising: a sine wave generator that generates and outputs a sine wave of a frequency; and an adder that adds the sine wave to the manipulated variable. The detected value when the sine wave of the frequency is output and the vibration amplitude of the output of the adder are stored, and the detected value when the sine wave of another frequency is output from the sine wave generator. Yo As the vibration amplitude of the output of the adder is stored, the magnitude of each vibration amplitude when a plurality of sine waves having different frequencies is output is stored, and the vibration amplitude of the detected value is The frequency of the sine wave signal generated by the sine wave generator when it is the minimum is the anti-resonance frequency WL to be controlled, and the sine wave generator is generated when the vibration amplitude of the output of the adder is minimum The process is characterized in that the frequency of the sine wave signal is set to the resonance frequency WH to be controlled.

  The invention according to claim 3 relates to a vibration frequency detection method for a motion control apparatus, a control object comprising a motor and a machine connected to the motor, a detector for detecting a state quantity of the motor, and the detection value. A closed-loop controller that performs control so that the command to the electric motor and the detected value coincide with each other and outputs an operation amount, a servo amplifier that inputs the operation amount and outputs an electric current for operating the electric motor, and a range to be detected In the vibration frequency detection method for a motion control apparatus, comprising: a sine wave generator that generates and outputs a swept sine wave in a frequency band of: and an adder that adds the swept sine wave to the manipulated variable. The time ta when the detected vibration amplitude of the detected value becomes the minimum is detected, the time tb when the vibration amplitude of the output of the adder becomes the minimum is detected, and the sweep sine wave generator is generated at the time ta Sine wave signal Is the anti-resonance frequency WL1 to be controlled, the frequency of the sine wave signal generated by the swept sine wave generator at time tb is the resonance frequency WH1 to be controlled, and from the sine wave generator to the vicinity of the anti-resonance frequency WL1. The vibration amplitude of the detected value when a sine wave of a certain frequency is output is stored, and the detection when a sine wave of another frequency near the anti-resonance frequency WL1 is output from the sine wave generator. The vibration amplitude of the detected value when a plurality of sine waves having different frequencies in the vicinity of the anti-resonance frequency WL1 is output is stored, and the detected value is stored. The frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the sine wave is the minimum is the anti-resonance frequency WL to be controlled, and a sine wave having a frequency near the resonance frequency WH1 is generated from the sine wave generator. When output The vibration amplitude of the output of the calculator is stored, and the vibration amplitude of the output of the adder when the sine wave generator outputs a sine wave of another frequency near the resonance frequency WH1 is stored. Thus, the magnitude of the vibration amplitude of the output of the adder when a plurality of sine waves having different frequencies near the resonance frequency WH1 is output is stored, and the vibration amplitude of the output of the adder is minimized. In this case, the frequency of the sine wave signal generated by the sine wave generator is processed as a control target resonance frequency WH.

  According to a fourth aspect of the present invention, in the vibration frequency detection method of the motion control apparatus according to any one of the first to third aspects, the process of detecting the time when the detected value or the output of the adder is minimum is performed. The time at which the sign of the signal is inverted is detected as the time at which the signal crosses zero, and the value of the signal at the intermediate time tc between the current zero crossing time and the previous zero crossing time is determined at time tc. This is characterized in that it is stored as vibration amplitude and processed in the procedure of detecting the time when the vibration amplitude becomes the minimum value.

The invention according to claim 5 relates to a motion control device, wherein a control object including an electric motor and a machine connected to the electric motor, a detection value for detecting a state quantity of the electric motor, and a command to the electric motor are matched. A motion control device comprising a closed loop controller that performs control and outputs an operation amount, and a servo amplifier that inputs the operation amount and outputs a current for operating the electric motor, in a frequency band in a range to be detected A sine wave generator that generates and outputs a swept sine wave, an adder that adds the swept sine wave to the manipulated variable, an output of the adder and the detected value, and the resonance frequency and antiresonance of the control target A vibration frequency detector for detecting a frequency, wherein the vibration frequency detector detects a time ta when the vibration amplitude of the detected value is minimum, and the vibration amplitude of the output of the adder is minimum time tb is detected, and the frequency of the sine wave signal generated by the sweep sine wave generator at time ta is set as the anti-resonance frequency WL to be controlled, and the frequency of the sine wave signal generated by the sweep sine wave generator at time tb is It is characterized by processing in the procedure of setting the resonance frequency WH to be controlled .

The invention according to claim 6 relates to a motion control device, wherein a control target comprising an electric motor and a machine connected to the electric motor, a detection value for detecting a state quantity of the electric motor, and a command to the electric motor coincide with each other. A motion control device comprising a closed-loop controller that performs control and outputs an operation amount, and a servo amplifier that inputs the operation amount and outputs a current for operating the electric motor, and a sine wave having a specified frequency A sine wave generator for generating and outputting the signal, an adder for adding the sine wave to the manipulated variable, and the output of the adder and the detected value are input to detect the resonance frequency and anti-resonance frequency of the controlled object A vibration frequency detector,
The vibration frequency detector stores the detected value when the sine wave generator outputs a sine wave of a certain frequency and the vibration amplitude of the output of the adder,
The sine wave generator outputs a plurality of sine waves having different frequencies such as storing the detected value when the sine wave of another frequency is output and the vibration amplitude of the output of the adder. The magnitude of each vibration amplitude at the time is stored, and the frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the detected value is minimum is set as the anti-resonance frequency WL to be controlled. ,
The frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the output of the adder is minimum is the resonance frequency WH to be controlled,
It is characterized by processing in the procedure .

According to the first aspect of the present invention, even when the resonance frequency and the anti-resonance frequency are low, the resonance frequency and the anti-resonance frequency can be detected at the same time without being affected by the closed loop controller at all. The resonance frequency and anti-resonance frequency can be detected well.
Further, according to the invention described in claim 2, it is possible to detect the resonance frequency and the anti-resonance frequency finely by limiting to a specific frequency, and further increase the detection accuracy.
According to the invention described in claim 3, the resonance frequency and anti-resonance frequency can be specified more precisely in the vicinity of the resonance frequency and anti-resonance frequency detected by the method of claim 1, and the detection accuracy is further improved. be able to.
According to the invention described in claim 4, the time with the smallest amplitude can be detected by a simple method, and the amount of calculation for detection can be reduced.
According to the device invention described in claim 5 , even when the resonance frequency and the anti-resonance frequency are low, the resonance frequency and the anti-resonance frequency can be detected at the same time without being influenced by the closed loop controller at all. A motion control device capable of accurately detecting the resonance frequency and the anti-resonance frequency is obtained.
Further, according to the device invention described in claim 6 , it is possible to obtain a motion control device that can detect the resonance frequency and the anti-resonance frequency finely by limiting to a specific frequency, and further improve the detection accuracy.

  Hereinafter, specific examples of the method of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a motion control apparatus that realizes a vibration frequency detection method for implementing the method of the present invention. In the figure, 1 is an electric motor, and 2 is a machine connected to the electric motor. A control object 10 is a combination of the electric motor 1 and the machine 2. Reference numeral 3 denotes a detector which detects the position or speed of the electric motor. A sine wave generator 4 outputs a sine wave dsin having a specific frequency. Reference numeral 5 denotes a servo amplifier which inputs an operation amount atref and outputs a current for driving the motor. Reference numeral 7 denotes a closed loop controller, which receives the position or speed command ref and the detection signal xfb detected by the detector 3 and outputs tref. Reference numeral 8 denotes an adder, which adds tref and dsin and outputs an operation amount atref after the addition. A vibration frequency detector 6 receives the detection signals xfb and atref and detects the resonance frequency WH and anti-resonance frequency WL of the controlled object itself.
Here, since the electric motor 1 and the machine 2 are coupled by an elastic element, resonance occurs there. The object of the present invention is to accurately estimate the frequency of the resonance.

FIG. 2 is a flowchart showing a processing procedure for detecting the vibration frequency in the motion control apparatus. The method of the present invention will be described step by step with reference to this figure.
First, in step 1, a swept sine wave signal dsin in a certain frequency band is output. What is necessary is just to set suitably the minimum frequency and the maximum frequency of a frequency band so that the resonant frequency of control object may be included in between.
Next, in step 2, the detection signal xfb while the sweep sine wave is being output and the output atref of the adder are acquired.
Next, in step 3, the time ta when the amplitude of the vibration of xfb is minimum and the time tb when the amplitude of the vibration of atref is minimum are stored. (Details will be described later)
Next, in step 4, the frequency of the sine wave signal generated by the sweep sine wave generator at time ta is set as the anti-resonance frequency WL to be controlled, and the sine wave signal generated by the sweep sine wave generator at time tb is set. The frequency is output as the resonance frequency WH to be controlled.

Next, details of a method for detecting the time at which the vibration amplitude of each signal is minimized in step 3 will be described.
FIG. 3 is a flowchart for explaining the method, and FIG. 4 is a diagram for clarifying symbols used in the description of the method.
Here, only the method for detecting the time at which the vibration amplitude of the signal xfb is minimum will be described, but the method for detecting the time at which the vibration amplitude of the signal atref is minimum may be exactly the same processing.
When the flow starts, xfb (t) at the time of this sampling is acquired in (S1).
In (S2), it is determined whether the sign is reversed (zero crossing) between xfb (t-Ts) at the previous sampling and xfb (t) at the current sampling,
If yes, set the current time as t0 and go to (s3).
If no, wait for the next sampling.
In (S3), a time tc intermediate between the time t0 and the time t0 # old at which the previous zero crossing is calculated and saved by the equation (1). The absolute value xfb (tc) of the signal at time tc is also stored. Then proceed to (S4).

tc = (t0 + t0 # old) / 2 (1)

In (S4), it is determined whether the absolute value of the stored signal xfb (tc) is smaller than the minimum absolute value xfb # min of the vibration amplitude so far.
If yes, go to step 5,
If no, proceed to (S7), save t0 as t0 # old, and wait for the next sampling.
(S5), xfb (tc) has the smallest amplitude so far,

xfb # min = absolute value of xfb (tc) (2)

Save as. Also, tc is stored as tc # min, and the process proceeds to (S6).
While the swept sine wave dsin is output in (S6), the process proceeds to (S7), stores t0 as t0 # old, and waits for the next sampling. When the output of the swept sine wave dsin disappears in (S6), the flow ends.
As described above, while the swept sine wave dsin is being output, the processes (S1) to (S5) are repeated. After completion of the sweep sine wave delivery, the time tc # min at the final time point is set as the time at which the vibration amplitude of the signal xfb is minimized.

Here, as an example, the waveform (simulation result) of each signal when a swept sine wave is input is shown in FIG.
Figure (a) shows the waveform of xfb (in this case, the speed of the motor) when a swept sine wave is input, and Figure (b) shows the atref when a swept sine wave is input. It is a waveform.
As is apparent from the figure, the time at which the vibration amplitude is maximum is difficult to detect from these waveforms, but the times ta and tb at which the vibration amplitude is minimum appear very significantly in the waveform.
In this way, instead of detecting the maximum absolute value of the response signal, the frequency of the swept sine wave when the vibration amplitude of the detection signal xfb is the smallest is determined as the anti-resonance frequency WL of the control target itself and the resonance frequency. At the same time, the frequency of the swept sine wave when the vibration amplitude of the manipulated variable atref after applying the swept sine wave is the smallest is determined as the resonance frequency WH of the control object itself, and the resonance frequency detection result Therefore, even if the resonance frequency and anti-resonance frequency are low, the resonance frequency and anti-resonance frequency can be detected at the same time without being affected by the closed-loop controller at all. An anti-resonance frequency can be detected.

The motion control device used in the second embodiment has the same configuration as the motion control device used in the first embodiment.
The difference between the present embodiment and the first embodiment is that the signal generated by the sine wave generator is a swept sine wave in the first embodiment, whereas in the second embodiment, a sine wave having a constant frequency is generated a plurality of times. It is about to output. This method is preferably used when it is desired to detect the vibration frequency with higher accuracy when the values of the resonance frequency WH and the anti-resonance frequency WL are roughly estimated in advance.

FIG. 6 is a flowchart showing the processing procedure of the second embodiment for detecting the vibration frequency in the motion control apparatus. The method of the present invention will be described step by step with reference to this figure. For example, suppose that it is known that both the machine resonance frequency and anti-resonance frequency are around 20 Hz.
In this case, W (1) = 19.2Hz, W (2) = 19.4Hz, W (3) = 19.6Hz, W (4) = 19.8Hz, W (5) = 20.0Hz, W (6) = 20.2 Ten frequencies W (i) of Hz, W (7) = 20.4 Hz, W (8) = 20.6 Hz, W (9) = 20.8 Hz, W (10) = 21.0 Hz are prepared.
When the flow starts, in step 1, first, a sine wave having a frequency of W (1) is output from the sine wave generator.
Next, in step 2, xfb and atref are acquired.
Next, in step 3, the amplitudes xfb # a (i) and atref # a (i) (i = 1, 2... 10) of vibrations of xfb and atref are measured. Here, when a sine wave having a constant frequency is input, since both the detected value xfb and atref are sine waves having a constant amplitude, the measurement of the amplitude is simple. For example, the simplest method is to store the maximum absolute value of the signal.
Next, in step 4, it is determined whether i is the last (i.e., when i = 10 in the present embodiment), and if it is not the last, steps 1 to 3 are repeated. If i is final (i = 10 in this embodiment), the process proceeds to step 5.
Step 5 detects the smallest value of xfb # a (i) and atref # a (i) from i = 1 to i = 10, and when the vibration amplitude xfb # a of the signal xfb is the smallest The input frequency W (i) is set as the anti-resonance frequency WL, and the input frequency W (i) when the vibration amplitude atref # a of the signal atref is minimum is output as the resonance frequency WH.
In this way, it is limited to a specific frequency, measures the vibration amplitude when inputting them one by one, and takes the procedure of finding the frequency of the sine wave that minimizes the vibration amplitude. The frequency can be detected, and the detection accuracy can be further increased.

In the third embodiment, after the method of the first embodiment is first performed, a plurality of frequencies are set in the vicinity of the vibration frequency detected by the method of the first embodiment, and the method of the second embodiment may be performed.
In this way, after inputting the first swept sine wave of a certain frequency band and detecting the resonance frequency and the anti-resonance frequency with a certain degree of accuracy, it is finer in the vicinity of the detected resonance frequency and the anti-resonance frequency. Can input the frequency one by one and specify the resonance frequency and the anti-resonance frequency at the frequency with the smallest vibration amplitude among them, so that the detection accuracy can be further improved.
In the above three embodiments, when finding the minimum value of the signal, the method of detecting the peak of the vibration amplitude of the signals xfb and atref (including the midpoint of the zero cross) is used. For example, a method of finding the minimum value of the signal after squaring the signal or integrating the signal may be used.

  After inputting a sweep sine wave, the frequency of the sweep sine wave when the detection signal xfb is the smallest is judged as the anti-resonance frequency WL of the control object itself, and the result is the resonance frequency detection result. At the same time, after applying the sweep sine wave Because the frequency of the swept sine wave when the manipulated variable atref is the smallest is judged as the resonance frequency WH of the control object itself, and the resonance frequency detection result is obtained, the resonance frequency and anti-resonance frequency can be accurately obtained even in a low frequency control object It can be detected and applied to applications such as low-rigidity semiconductor transfer robots and space robots.

It is a block diagram which shows the structure of the motion control apparatus to which the method of this invention is applied. It is a flowchart which shows the process sequence of the method of this invention. It is a flowchart which shows the process sequence of the principal part of this invention. It is a figure explaining how to obtain | require the minimum value of the vibration amplitude of the signal of this invention. It is a figure which shows the simulation result of this invention. It is a flowchart which shows the process sequence of the 2nd method of this invention. It is a block diagram which shows the structure of the motion control apparatus to which the conventional method is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Machine 3 Detector 4 Sine wave generator 5 Servo amplifier 6 Vibration frequency detector 7 Closed loop controller 10 Control object 100 Motion control apparatus 51 Command generator 52 Controller 53 Electric motor 54 Machine 55 Detector 56 Signal processor 57 Closed loop controller

Claims (6)

A control object comprising a motor and a machine connected to the motor;
A detector for detecting a state quantity of the motor;
A closed-loop controller that outputs an operation amount by performing control so that the detected value and a command to the motor coincide with the detected value; and a servo amplifier that inputs the operation amount and outputs a current for operating the electric motor; A sine wave generator that generates and outputs a swept sine wave in a frequency band in a range to be detected; an adder that adds the swept sine wave to the manipulated variable;
In the vibration frequency detection method of the motion control device equipped with
Detect the time ta when the vibration amplitude of the detected value detected by the detector is minimum,
Detect the time tb when the vibration amplitude of the output of the adder is minimum,
The frequency of the sine wave signal generated by the sweep sine wave generator at time ta is the anti-resonance frequency WL to be controlled,
A motion control characterized by detecting a resonance frequency and an anti-resonance frequency of the controlled object in a procedure that the frequency of the sine wave signal generated by the swept sine wave generator at time tb is set as a resonance frequency WH of the controlled object Device vibration frequency detection method. A control object comprising a motor and a machine connected to the motor;
A detector for detecting a state quantity of the motor;
A closed-loop controller that outputs an operation amount by performing control so that the detected value and a command to the motor coincide with the detected value; and a servo amplifier that inputs the operation amount and outputs a current for operating the electric motor; A sine wave generator for generating and outputting a sine wave of a specified frequency, an adder for adding the sine wave to the manipulated variable,
In the vibration frequency detection method of the motion control device equipped with
From the sine wave generator, the detected value when a sine wave of a certain frequency is output and the vibration amplitude of the output of the adder are stored,
The sine wave generator outputs a plurality of sine waves having different frequencies such as storing the detected value when the sine wave of another frequency is output and the vibration amplitude of the output of the adder. The magnitude of each vibration amplitude at the time is stored, and the frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the detected value is minimum is set as the anti-resonance frequency WL to be controlled. ,
The frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the output of the adder is minimum is the resonance frequency WH to be controlled,
A vibration frequency detection method for a motion control apparatus, wherein a resonance frequency and an anti-resonance frequency of the control object are detected by the following procedure. A control object comprising a motor and a machine connected to the motor;
A detector for detecting a state quantity of the motor;
A closed-loop controller that outputs an operation amount by performing control so that the detected value and a command to the motor coincide with the detected value; and a servo amplifier that inputs the operation amount and outputs a current for operating the electric motor; A sine wave generator that generates and outputs a swept sine wave in a frequency band in a range to be detected; an adder that adds the swept sine wave to the manipulated variable;
In the vibration frequency detection method of the motion control device equipped with
Detect the time ta when the vibration amplitude of the detected value detected by the detector is minimum,
Detect the time tb when the vibration amplitude of the output of the adder is minimum,
The frequency of the sine wave signal generated by the swept sine wave generator at time ta is defined as the anti-resonance frequency WL1 to be controlled,
The frequency of the sine wave signal generated by the sweep sine wave generator at time tb is the resonance frequency WH1 to be controlled,
From the sine wave generator, the vibration amplitude of the detected value when a sine wave having a frequency near the anti-resonance frequency WL1 is output is stored,
A plurality of different frequencies in the vicinity of the anti-resonance frequency WL1, such as storing the vibration amplitude of the detected value when a sine wave of another frequency in the vicinity of the anti-resonance frequency WL1 is output from the sine wave generator. The magnitude of the vibration amplitude of the detected value when the detected sine wave is output is stored, and the frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the detected value is minimum is stored. Let the anti-resonance frequency WL to be controlled be
The vibration amplitude of the output of the adder when the sine wave generator outputs a sine wave having a frequency near the resonance frequency WH1 is stored,
From the sine wave generator, the vibration amplitude of the output of the adder when a sine wave of another frequency near the resonance frequency WH1 is output is stored.
The magnitude of the vibration amplitude of the output of the adder when a plurality of sine waves having different frequencies near the resonance frequency WH1 is output is stored, and the vibration amplitude of the output of the adder is minimum. The frequency of the sine wave signal generated by the sine wave generator is the resonance frequency WH to be controlled.
A vibration frequency detection method for a motion control apparatus, wherein a resonance frequency and an anti-resonance frequency of the control object are detected by the following procedure.   In the process of detecting the time when the detected value or the output of the adder becomes minimum, the time when the sign of the signal is inverted is detected as the time when the signal crosses 0, and the time when the current 0 crosses and the previous time 0 The signal value at the intermediate time tc of the crossing time is stored as the vibration amplitude at the time tc, and the processing is performed by the procedure of detecting the time when the vibration amplitude becomes the minimum value. The vibration frequency detection method of the motion control apparatus according to any one of claims 1 to 3. A control object comprising a motor and a machine connected to the motor;
A closed loop controller that outputs a manipulated variable by performing control so that a detection value for detecting a state quantity of the motor matches a command to the motor, and outputs a current for operating the motor by inputting the manipulated variable A sine wave generator that generates and outputs a swept sine wave in a frequency band in a range to be detected, an adder that adds the swept sine wave to the manipulated variable, A vibration frequency detector for inputting the output of the adder and the detection value and detecting a resonance frequency and an anti-resonance frequency of the controlled object;
The vibration frequency detector detects a time ta when the vibration amplitude of the detected value is minimum, detects a time tb when the vibration amplitude of the output of the adder is minimum, and sweeps at the time ta The frequency of the sine wave signal generated by the sine wave generator is set as the anti-resonance frequency WL to be controlled, and the frequency of the sine wave signal generated by the sweep sine wave generator at time tb is set as the control target resonance frequency WH. processing the motion control device, characterized by. A control object comprising a motor and a machine connected to the motor;
A closed loop controller that outputs a manipulated variable by performing control so that a detection value for detecting a state quantity of the motor matches a command to the motor, and outputs a current for operating the motor by inputting the manipulated variable A sine wave generator that generates and outputs a sine wave having a specified frequency, an adder that adds the sine wave to the manipulated variable, and a A vibration frequency detector for inputting an output and the detection value and detecting a resonance frequency and an anti-resonance frequency of the control object;
The vibration frequency detector stores the detected value when the sine wave generator outputs a sine wave of a certain frequency and the vibration amplitude of the output of the adder,
The sine wave generator outputs a plurality of sine waves having different frequencies such as storing the detected value when the sine wave of another frequency is output and the vibration amplitude of the output of the adder. The magnitude of each vibration amplitude at the time is stored, and the frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the detected value is minimum is set as the anti-resonance frequency WL to be controlled. ,
The frequency of the sine wave signal generated by the sine wave generator when the vibration amplitude of the output of the adder is minimum is the resonance frequency WH to be controlled,
A motion control device characterized by processing in the procedure

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