JP5659749B2 - Method and apparatus for correcting angle transmission error of wave gear reducer - Google Patents

Description

  The present invention provides a wave for correcting an angle transmission error in the wave gear reducer when a rotary body such as a blanket roll of an offset printing apparatus is driven to rotate by a drive motor connected via a wave gear reducer. The present invention relates to an angle transmission error correction method and apparatus for a gear reducer.

  A wave gear reducer (a reducer using a harmonic drive (registered trademark) mechanism), which is one of the reducers, is fixed to a casing, a wave generator attached to an input shaft, a flex spline attached to an output shaft, and a casing. It has a structure consisting of a circular spline and has features such as small size, light weight, high rotation accuracy, high reduction ratio, high torque capacity, high efficiency, and no backlash, so it has high positioning accuracy (controllability of rotation angle). Is widely used in applications that require

  Therefore, in the offset printing apparatus, it is conventionally considered that a drive motor such as a servo motor is attached to one end of the roll shaft of the blanket roll via a wave gear reducer as a rotation drive mechanism of the blanket roll. ing.

  By the way, in recent years, an image display element such as a liquid crystal display on a substrate using a printing technique using a conductive paste as a printing ink, for example, an intaglio offset printing technique, instead of fine processing such as etching of a metal vapor deposition film. There has been proposed a method of forming the electronic circuit by printing.

  When an electronic circuit is formed on the substrate by printing, the line width to be an electrode may be required to be as fine as, for example, about 10 μm. Higher printing accuracy is required compared to offset printing.

  In the offset printing apparatus, since the rotational accuracy of the blanket roll is directly related to the printing accuracy, in the offset printing apparatus that requires high printing accuracy as described above, it is necessary to control the rotation of the printing roll with high accuracy.

  However, the actual condition of the wave gear reducer is that, as its characteristics, a periodic angle transmission error of one cycle occurs every time the servo motor shaft connected to the input side rotates twice.

  Regarding the angle transmission error of this wave gear reducer, it is usually said that precise rotation control is possible by measuring the rotation angle on the output side with a precision rotary encoder and feeding it back to the input side with a control device. Yes. However, when the rotational speed is high or the rotational inertia of the output side shaft is larger than the output of the motor depending on the driving object connected to the output side shaft, the amount of angular transmission error of the wave gear reducer The error cannot be corrected.

  Also, the angle transmission error of the wave gear reducer prints characters and images on paper or the like because the deflection width on the side preceding and behind the rotation direction is as small as about 0.01 to 0.02 degrees, for example. This is not a problem with normal offset printing, but when high printing accuracy is required, such as when an electronic circuit is formed on a substrate as described above, the angle transmission error of the wave gear reducer affects. There is concern about fear.

  A spectroscope provided with a motor, a wave gear reducer for reducing the rotation of the motor, and a wavelength dispersion element (diffraction grating) whose angle is changed (oscillated) by a rotational driving force decelerated by the reducer. As a method for correcting the wavelength error of the spectrometer when taking out monochromatic light having a specific wavelength, the angle of the wave gear reducer interposed between the motor and the wavelength dispersion element (diffraction grating) A method has been conventionally proposed in which a transmission amount is expressed as a superposition of a sin function (periodic function), a correction amount is calculated, and a command value given to the motor is corrected based on the obtained correction amount. According to this method, it is said that the periodic error peculiar to the wave gear reducer interposed between the motor and the wavelength dispersion element (diffraction grating) can be reduced (for example, see Patent Document 1). .

Japanese Patent No. 4254454

  However, the method disclosed in Patent Document 1 described above is used when an approximate correction expression is expressed in which the periodic error waveform of the wave gear reducer is expressed by a linear combination of two or more periodic functions having periodicity. Only the sine function for two coefficients experimentally determined based on the measurement result of the emission line spectrum, specifically, among the spatial frequency when the angle transmission error generated in the wave gear reducer is subjected to fast Fourier transform (FFT), The fact is that only the sine function corresponding to the first frequency and the second frequency is used, and for this purpose, this method is provided with a configuration in which a rotating body is rotationally driven by a motor via a wave gear reducer. If the device is applied to the correction of the angle transmission error of the wave gear reducer over the entire 360 ° circumference during rotation of the rotating body, the following problems occur.

  That is, in the technique disclosed in Patent Document 1, the object driven by the motor via the wave gear reducer is the angle change (swing) of the wavelength dispersion element (diffraction grating) in the spectroscope. The shaft on the output side of the speed reducer does not rotate but only reciprocates within a limited angular range. In addition, the angle transmission error required for the wave gear reducer is static when a wavelength dispersive element (diffraction grating) attached to the output shaft of the wave gear reducer is fixed to a certain angle posture. It's just an error about the wrong state. Therefore, as described above, the correction formula approximating the periodic error waveform of the wave gear reducer corresponds to the first frequency and the second frequency when the angle transmission error generated in the wave gear reducer is subjected to fast Fourier transform. Even if only the sine function is used, the angle correction effect of the wave gear reducer is sufficient to achieve the purpose of correcting the wavelength error of the spectroscope when taking out monochromatic light having a specific wavelength from the spectroscope. It was possible to get

  However, according to the research of the present inventor, the wave gear reducer is used when the rotating body is rotationally driven in an apparatus having a configuration in which the rotating body is rotationally driven by a motor via the wave gear reducer. When the angle transmission error is corrected, it is necessary to suppress the angle transmission error in a dynamic state. Therefore, a correction formula approximating the periodic error waveform of the wave gear reducer is generated in the wave gear reducer. It was found that the sinusoidal function corresponding to the first frequency and the second frequency when the angle transmission error is fast Fourier transformed (FFT) cannot be sufficiently approximated.

  Moreover, even if the angle transmission error of the wave gear reducer is corrected using the deformation correction formula obtained by the method shown in Patent Document 1, the angle of the shaft on the output side of the wave gear reducer is When rotating 360 degrees, the intensity (amplitude) of the corrected periodic error waveform of the wave gear reducer and the phase of the waveform periodically depend on the angle of the shaft on the output side of the wave gear reducer. It also turned out to be changing.

  Therefore, the present invention rotates the shaft on the output side of the wave gear reducer when a rotating body such as a blanket roll of an offset printing apparatus is rotationally driven by a drive motor connected via the wave gear reducer. In the dynamic state, the angle transmission error of the wave gear reducer can be efficiently corrected, and the rotation is performed over the entire area in the circumferential direction when the output shaft of the wave gear reducer is rotated 360 degrees. An object of the present invention is to provide a method and an apparatus for correcting an angle transmission error of a wave gear reducer so that the angle error can be suppressed uniformly.

In order to solve the above-mentioned problem, the present invention, corresponding to claim 1, shows the periodic angular transmission error waveform of a wave gear reducer attached between a drive motor and a rotating body to be rotated, as the wave gear. It is approximated by a linear combination of two or more periodic functions having a periodicity of 1 / n (n is a natural number depending on the structure of the wave gear reducer) corresponding to one rotation on the input shaft side of the speed reducer. The provisional correction formula is expressed by using a sine function related to at least the fourth frequency ω4 from the first frequency ω1 obtained when the angle transmission error of the wave gear reducer is fast Fourier transformed . As for the amplitude A in the term of A · sin (ω1 · θ + θa), which is the term of the sin function for one frequency ω1 , the amplitude a1 for the fluctuation of the amplitude A depending on the rotation angle of the shaft on the output side of the wave gear reducer Phase θα A correction for multiplying a change amount sin (a1 · θ + θα) obtained by approximating an angle-dependent change with respect to the output-side axis of the wave gear reducer by a sin function , and the first frequency ω1 in the provisional correction formula Regarding the phase θa in the term of A · sin (ω1 · θ + θa) that is the term of the sin function, the amplitude Δθa , the period dα1 and the phase of the fluctuation of the phase θa depending on the rotation angle of the shaft on the output side of the wave gear reducer A correction equation is obtained by adding a correction that multiplies a correction amount (1−Δθa · sin (dα1 · θ + dθα)) obtained by approximating the angle-dependent change of dθα with respect to the output-side axis of the wave gear reducer by a sin function, A wave that corrects the target rotation angle of the rotating body by the obtained correction formula and gives a control command to the drive motor so as to obtain the corrected target rotation angle of the rotating body. An angle transmission error correction method for a dynamic gear reducer is adopted.

According to a second aspect of the present invention, the drive motor is connected to the rotating body via the wave gear reducer, the input side angle detecting means for detecting the angle on the input side of the wave gear reducer, and the wave An output side angle detecting means for detecting an angle on the output side of the gear reducer, and a control device, and the control device is configured to rotate the rotating body via the wave gear reducer by the drive motor; A function for obtaining a periodic angle transmission error waveform of the wave gear reducer based on the signals input from the angle detection means and the output side angle detection means, and a period corresponding to one rotation on the input shaft side of the wave gear reducer Of a temporary correction equation approximated by a linear combination of two or more periodic functions having a periodicity of 1 / n (where n is a natural number depending on the structure of the wave gear reducer). Obtained when fast Fourier transform the error Represents using the sin function relating to at least a fourth frequency ω4 from the first frequency .omega.1, further, the amplitude A in terms of a term of a sin function for the first frequency .omega.1 in the temporary correction equation A · sin (ω1 · θ + θa) For the fluctuation of the amplitude A depending on the rotation angle of the shaft on the output side of the wave gear reducer, the angle-dependent change of the amplitude a1 and phase θα with respect to the output side shaft of the wave gear reducer is approximated by a sin function. becomes a correction amount sin (a1 · θ + θα) a correction for multiplying added, and the phase .theta.a in terms of a term of a sin function for the first frequency .omega.1 in the temporary correction equation a · sin (ω1 · θ + θa), The amplitude Δθa of the fluctuation of the phase θa depending on the rotation angle of the shaft on the output side of the wave gear reducer, the axis on the output side of the wave gear reducer having the period dα1 and the phase dθα. A function of storing a correction formula obtained by adding a correction by multiplying a correction amount (1−Δθa · sin (dα1 · θ + dθα)) obtained by approximating an angle-dependent change with a sin function, and operating the drive motor When the rotating body is rotated via the wave gear reducer, the target rotating angle of the rotating body is corrected by the stored correction formula so that the corrected target rotating angle of the rotating body is obtained. An angle transmission error correction apparatus for a wave gear reducer having a configuration provided with a function of giving a control command to the drive motor.

According to the present invention, the following excellent effects are exhibited.
(1) The periodic angle transmission error waveform of the wave gear reducer attached between the drive motor and the rotating body to be rotated is represented by 1 / n of a cycle corresponding to one rotation on the input shaft side of the wave gear reducer. (N is a natural number depending on the structure of the wave gear reducer) A temporary correction equation approximated by a linear combination of two or more periodic functions having a periodicity, and the angle transmission error of the wave gear reducer as fast Fourier It is expressed by using a sin function relating to at least the fourth frequency ω4 from the first frequency ω1 obtained at the time of conversion, and further, A · sin (ω1 · θ + θa) which is a term of the sine function relating to the first frequency ω1 in the provisional correction formula . the amplitude a of the section), the angle-dependent change to the output side of the axis of the amplitudes a1 and phase θα wave gear drive for shake amplitude a dependent on the rotation angle of the output side of the axis of the harmonic drive gear reducer A correction that multiplies a correction amount sin (a1 · θ + θα) approximated by a sin function is added, and A · sin (ω1 · θ + θa), which is a term of the sin function related to the first frequency ω1 in the provisional correction equation , As for the phase θa in the term, the angle-dependent change of the amplitude Δθa , the period dα1 and the phase dθα of the fluctuation of the phase θa with respect to the output side axis of the wave gear reducer, depending on the rotation angle of the output side shaft of the wave gear reducer. Is obtained by adding a correction that is multiplied by a correction amount (1−Δθa · sin (dα1 · θ + dθα)) approximated by a sin function, and the target rotation angle of the rotating body is determined by the obtained correction equation. As a method and apparatus for correcting an angle transmission error of a wave gear reducer that gives a control command to the drive motor so that the corrected target rotational angle of the rotating body is obtained. Therefore, when the rotary body is rotationally driven by the drive motor via the wave gear reducer, the cyclic angle transmission error that the wave gear reducer has as a characteristic is caused to generate a rotational driving force by the wave gear reducer. The correction can be performed efficiently under the dynamic state of transmission. Furthermore, the rotation angle error can be uniformly suppressed without depending on the rotation angle of the shaft on the output side of the wave gear reducer, that is, over the entire region in the circumferential direction when the shaft is rotated 360 degrees. . Therefore, the rotation accuracy and positioning accuracy of the rotating body can be increased.
(2) Accordingly, the angle transmission error correction method and apparatus for a wave gear reducer according to the present invention is applied to an offset printing apparatus in which a blanket roll is connected to a drive motor via a wave gear reducer. By correcting the angle transmission error, it is possible to improve the rotation accuracy and positioning accuracy of the blanket roll, so that it is possible to improve the printing accuracy in the offset printing process and This can be advantageous when high printing accuracy is required, such as when an electronic circuit is formed by printing.

It is the schematic which shows the example applied to the rotational drive part of the blanket roll of an offset printing apparatus as one Embodiment of the angle transmission error correction method and apparatus of the wave gear reducer of this invention. 1 shows an effect of suppressing an angle transmission error of a wave gear reducer obtained by applying the method of correcting an angle transmission error of a wave gear reducer of the present invention to the apparatus of FIG. The angle transmission error of the machine is plotted with the rotation angle of the shaft on the output side of the wave gear reducer as the horizontal axis, (b) is a diagram showing the frequency distribution by FFT of the angle transmission error of the wave gear reducer. is there. As a comparison of the effects of applying the method for correcting the angle transmission error of the wave gear reducer of the present invention, the angle transmission error is calculated as a correction formula approximating the periodic error waveform of the wave gear reducer with respect to the angle transmission error of the wave gear reducer. Shows the change in the angle transmission error when using the correction formula expressed using the sine function corresponding to the first to fourth spatial frequencies when fast Fourier transform is performed. The angle transmission error of the gear reducer is a plot in which the rotation angle of the shaft on the output side of the wave gear reducer is plotted on the horizontal axis. (B) shows the frequency distribution by FFT of the angle transmission error of the wave gear reducer. FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 and 2 show an embodiment of a method and apparatus for correcting an angle transmission error of a wave gear reducer according to the present invention, for example, when applied to a blanket roll drive mechanism of an offset printing apparatus as shown in FIG. It is as follows.

  Here, the drive mechanism of the blanket roll shown in FIG. 1 will be outlined. The roll shafts 2a and 2b at both ends of the blanket roll 1 as a rotating body are connected to the roll holder 3 extending along the axial direction of the blanket roll 1. Both ends are rotatably supported via individual bearings 4.

  An output side shaft (not shown) of the wave gear reducer 5 is attached to the end of the roll shaft 2a on one end side (left side in FIG. 1) of the blanket roll 1, and the input side of the wave gear reducer 5 is attached. In this configuration, an output shaft 7 of a drive motor 6 such as a servo motor is connected.

  An angle transmission error correction device for a wave gear reducer according to the present invention applied to the drive mechanism of the blanket roll 1 having the above-described configuration is provided to the drive motor 6 through detection of the rotation angle of the output shaft of the drive motor 6 itself. An input side angle detecting rotary encoder 8 as an input side angle detecting means for detecting an input angle of the wave gear reducer 5 is provided, and the other end side of the blanket roll 1 which is the rotating body (the right side in FIG. 1). The output side angle detecting rotary encoder 9 as an output side angle detecting means for detecting the output angle of the wave gear reducer 5 through the detection of the rotation angle of the blanket roll 1 is attached to the roll shaft 2b. .

  Further, a control device 10 is provided that gives a command to the drive motor 6 based on signals inputted from the angle detection rotary encoders 8 and 9 on the input side and output side of the wave gear reducer 5. .

  Hereinafter, the control contents in the control device 10 will be described in detail.

  Here, first, the derivation of the control law in the control device 10 will be described.

  When the blanket roll 1 is rotationally driven by the drive motor 6 via the wave gear reducer 5, the control device 10 receives the input side angle detection rotary encoder 8 from the input side of the wave gear reducer 5. Based on the angle detection signal and the angle detection signal on the output side of the wave gear reducer 5 input from the output side angle detection rotary encoder 9, an angle transmission error in the wave gear reducer 5 is detected.

  By the way, as described above, the sin function corresponding to the first frequency and the second frequency when the angle transmission error generated in the wave gear reducer is fast Fourier transformed (FFT) as shown in Patent Document 1 is used. In the correction formula approximating the periodic error waveform of the wave gear reducer expressed as follows, when the blanket roll 1 is rotationally driven by the drive motor 6 via the wave gear reducer 5, the wave gear reducer 5 It has been found that angle transmission errors in a dynamic state cannot be suppressed.

In view of this, first, an approximated error waveform of the wave gear reducer 5 is expressed by a linear combination of two or more periodic functions having periodicity in the same manner as described in Patent Document 1. In order to increase the term of the sin function, which is a periodic function related to the spatial frequency when the angle transmission error generated in the wave gear reducer 5 is subjected to fast Fourier transform (FFT) when the temporary correction formula is established, for example, the first frequency Consider a provisional correction formula that approximates the periodic error waveform of the wave gear reducer 5 using the sin function corresponding to the fourth frequency ω4 from ω1. In this case, when the sine function corresponding to the first frequency ω1 to the fourth frequency ω4 is used, the temporary correction formula is as shown in the following correction formula (1).

  When the angle control command given to the drive motor 6 is corrected using the correction equation (1) obtained as described above, the wave gear reducer 5 input from the angle detection rotary encoders 8 and 9 is used. As a result of the angle transmission error in the wave gear reducer 5 detected by the control device 10 based on the angle detection signals on the input side and the output side, the rotation angle of the shaft on the output side of the wave gear reducer 5 When plotted as an axis, the waveform is as shown in FIG. Further, when this angle transmission error is fast Fourier transformed (FFT), it is as shown in FIG.

  Paying attention to the result of FIG. 3A, the waveform of the angle transmission error in the wave gear reducer 5 corrected by the correction equation (1) has the strength, that is, the amplitude and the phase of the waveform. It has been clarified that it fluctuates depending on the rotation angle of the shaft on the output side of the wave gear reducer 5 (causes shake).

Therefore, based on the envelope curve in the graph of FIG. 3A, the first term in the correction equation (1), which is the provisional correction equation, that is, the angle transmission error generated in the wave gear reducer 5 is represented by the fast Fourier transform. For the amplitude A in the term A · sin (ω1 · θ + θa), which is the term of the sine function relating to the first frequency ω1 among the spatial frequencies when transformed (FFT), the amplitude of fluctuation (variation) of the amplitude A ( A correction for multiplying a correction amount sin (a1 · θ + θα) obtained by approximating the angle-dependent change of the a1) and the phase (θα) with respect to the output shaft of the wave gear reducer 5 by a sin function as a periodic function is added. To do.

Further, regarding the phase θa in the term of A · sin (ω1 · θ + θa) which is the term of the sin function relating to the first frequency ω1, the magnitude (amplitude) (Δθa) and the period ( By applying a correction that multiplies a correction amount (1−Δθa · sin (dα1 · θ + dθα)) for the angle-dependent change of dα1) and phase (dθ α ) with respect to the output-side shaft of the wave gear reducer 5, the following correction is performed. Equation (2) is derived.

  When the angle control command given to the drive motor 6 is corrected using the correction formula (2), the input side and the output side of the wave gear reducer 5 input from the angle detection rotary encoders 8 and 9 are corrected. The result of the angle transmission error in the wave gear reducer 5 detected by the control device 10 based on the angle detection signal is plotted when the rotation angle of the output side shaft of the wave gear reducer 5 is plotted as a horizontal axis. The waveform is as shown in (a). Further, when this angle transmission error is fast Fourier transformed (FFT), it becomes as shown in FIG.

  When the waveform of FIG. 2 (a) is compared with the waveform of FIG. 3 (a) described above, the amplitude (intensity) of the angle transmission error in the wave gear reducer 5 is reduced, and the wave gear deceleration of the amplitude is performed. It is apparent that fluctuations depending on the rotation angle of the shaft on the output side of the machine 5 are also reduced.

  When the above equation (2) is derived from the above-described provisional correction equation (1), the second term to the fourth term on the right side in the equation (2) are added to the first term on the right side. Although the same correction may be made as described above, since it often does not work independently, the adjustment of the parameters becomes complicated, but it does not contribute much to the suppression of the angle transmission error of the wave gear reducer 5. Therefore, normally, as described above, it is preferable to modify only the first term on the right side in Equation (2).

  Each parameter of the correction term added in the above equation (2) is set to a waveform similar to that shown in FIG. 3 (a) obtained after the correction by the above correction equation (1) on the output side of the wave gear reducer 5. 360 degrees of the entire axis of the axis, and the change of the amplitude and phase is obtained, and the magnitude and spatial frequency of the amplitude and phase variation are read based on the waveform envelope of FIG. By fitting), the values of the three parameters included in the correction term can be obtained.

  The effect of the correction added to the above equation (2) can be confirmed by calculating the amplitude and standard deviation of the angle transmission error, even if it is difficult to understand simply by looking at the waveform. Therefore, the result may be used for fine adjustment of the parameter.

  In view of the above, in the present invention, the correction equation (2) obtained in the above procedure is stored in the control device 10 in advance, and the operation of the drive motor 6 causes the wave gear reducer 5 to pass through. When the blanket roll 1 is rotationally driven, the control device 10 corrects the target rotation angle of the blanket roll 1 using the correction formula (2), and the corrected target rotation of the blanket roll 1 is corrected. A control command is given to the drive motor 6 so that an angle can be obtained.

  Further, when the control device 10 gives a control command for obtaining the target rotation angle of the blanket roll 1 corrected by the correction formula (2) to the drive motor 6, the input side angle detection rotary encoder 8 Control for command value tracking such as feedback control is performed on the drive motor 6 so that the input angle detection signal of the wave gear reducer 5 matches the angle control command given to the drive motor 6. May be performed.

  Thus, according to the angle transmission error correction method and apparatus for the wave gear reducer of the present invention, when the blanket roll 1 that is a rotating body is driven to rotate by the drive motor 6 via the wave gear reducer 5, Under the dynamic state in which the rotational driving force is transmitted via the wave gear reducer 5, the cyclic angle transmission error that the wave gear reducer 5 has as a characteristic, the wave gear reducer 5 An angle transmission error can be efficiently corrected, and it does not depend on the rotational angle of the shaft on the output side of the wave gear reducer 5, that is, over the entire circumferential direction when the shaft is rotated 360 degrees, The rotation angle error can be suppressed uniformly.

  Therefore, the rotational accuracy and positioning accuracy of the blanket roll 1 can be increased, and the printing accuracy in the offset printing apparatus can be improved. Therefore, the electronic circuit is high on the substrate by printing. It can be made suitable for a roll rotation drive device for rotationally driving the blanket roll 1 in an offset printing apparatus that requires printing accuracy.

  Note that the present invention is not limited to the above-described embodiment, and the angle transmission error generated in the wave gear reducer 5 is fast Fourier transformed ( You may make it add the sine function corresponding to the 5th frequency in the periodic function regarding the spatial frequency at the time of FFT.

  The method and apparatus for correcting the angle transmission error of the wave gear reducer according to the present invention is offset printing as long as the output of the drive motor is transmitted to the rotating body via the wave gear reducer to drive the rotating body. You may apply to the drive mechanism of any rotary body other than the blanket roll in an apparatus.

  Of course, various modifications can be made without departing from the scope of the present invention.

1 Blanket roll (rotating body)
5 Wave Gear Reducer 6 Drive Motor 8 Input Side Angle Detection Rotary Encoder (Input Side Angle Detection Means)
9 Output side angle detection rotary encoder (output side angle detection means)
10 Control device

Claims (2)

The cyclic angle transmission error waveform of the wave gear reducer attached between the drive motor and the rotating body to be rotated is represented by 1 / n (n is a cycle corresponding to one rotation on the input shaft side of the wave gear reducer. When performing a fast Fourier transform on the angular transmission error of a wave gear reducer using a temporary correction formula that approximates a linear combination of two or more periodic functions having a periodicity of (natural number depending on the structure of the wave gear reducer) Is expressed by using a sine function relating to at least the fourth frequency ω4 from the first frequency ω1 obtained in the above, and further, a term of A · sin (ω1 · θ + θa) which is a term of the sine function relating to the first frequency ω1 in the provisional correction formula the amplitude a, the angle-dependent change to the output side of the axis of the amplitudes a1 and phase θα wave gear drive for shake amplitude a dependent on the rotation angle of the output side of the axis of the harmonic drive gear reducer sin in A term of A · sin (ω1 · θ + θa), which is a term of a sin function related to the first frequency ω1 in the above provisional correction formula, is added by multiplying a correction amount sin (a1 · θ + θα) approximated by a function. In the phase θa , the amplitude Δθa of the fluctuation of the phase θa , the period dα1, and the phase dθα with respect to the output side shaft of the wave gear reducer depending on the rotation angle of the output side shaft of the wave gear reducer. A correction formula obtained by adding a correction multiplied by a correction amount (1−Δθa · sin (dα1 · θ + dθα)) approximated by a sin function is obtained, and the target rotation angle of the rotating body is determined by the obtained correction formula. An angle transmission error correction method for a wave gear reducer, characterized in that a control command is given to the drive motor so as to obtain a corrected target rotational angle of the rotating body. A drive motor is connected to the rotating body via a wave gear reducer, and further, input side angle detecting means for detecting the angle on the input side of the wave gear reducer and the angle on the output side of the wave gear reducer are detected. Output side angle detecting means and a control device, and when the control device rotates the rotating body via the wave gear reducer by the drive motor, the input side angle detecting means and the output side angle detecting means. And a function for obtaining a cyclic angle transmission error waveform of the wave gear reducer based on a signal inputted from the input signal, and 1 / n of a period corresponding to one rotation on the input shaft side of the wave gear reducer (n is a wave gear reduction) A temporary correction equation approximated by a linear combination of two or more periodic functions having a periodicity of (natural number depending on the machine structure) is obtained when the angular transmission error of the wave gear reducer is fast Fourier transformed. small from the first frequency ω1 Both expressed using the sin function relating fourth frequency .omega.4, further, the amplitude A in terms of a term of a sin function for the first frequency .omega.1 in the temporary correction equation A · sin (ω1 · θ + θa), the wave gear reduction A correction amount sin () obtained by approximating an angle-dependent change of the amplitude a1 and the phase θα with respect to the output-side shaft of the wave gear reducer depending on the rotation angle of the output-side shaft of the machine by a sin function. For the phase θa in the term of A · sin (ω1 · θ + θa), which is a term of the sin function relating to the first frequency ω1 in the provisional correction formula, with a correction to multiply by a1 · θ + θα) , the wave gear reducer The change in the angle Δθa , the period dα1 and the phase dθα of the fluctuation of the phase θa depending on the rotation angle of the output side shaft with respect to the output side shaft of the wave gear reducer is represented by si a function of storing a correction formula obtained by adding a correction multiplied by a correction amount (1−Δθa · sin (dα1 · θ + dθα)) approximated by an n function, and a wave gear reducer by operating the drive motor. When the rotating body is rotated via the drive motor, the target rotating angle of the rotating body is corrected by the stored correction formula, and the corrected rotating body target rotating angle is obtained. An angle transmission error correction device for a wave gear reducer, characterized by having a structure having a function of giving a control command.

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