JP2011133938A - Apparatus and method for identifying vibration characteristic of conveyance device, and conveyance system using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for identifying vibration characteristics of a conveyance device while reducing the time required for identifying vibration characteristics and improving identifying accuracy. <P>SOLUTION: The vibration characteristic identification device 2 includes a vibration sensor 21 for detecting vibration generated by the conveyance operation of a conveyance device 103. Natural angular frequency corresponding to a natural frequency as one of vibration characteristics is specified for each vibration mode, based on the vibration detected by the vibration sensor 21. The vibration detected by the vibration sensor 21 is separated by vibration mode by using the natural angular frequency corresponding to each specified natural frequency. Attenuation coefficients as one of the vibration characteristics are specified for each vibration mode, based on the separated vibration and the natural angular frequency corresponding to the specified natural frequency. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an apparatus for identifying vibration characteristics based on vibrations generated by a transport operation of a transport apparatus, an identification method, and a transport system using these, and in particular, vibration characteristic identification of a transport apparatus with optimized identification of vibration characteristics. The present invention relates to an apparatus, a method for identifying vibration characteristics of a transfer apparatus, and a transfer system using these.

  In a transport device that transports an object to be transported by driving a transport mechanism such as a robot arm or a gantry loader, vibration may occur due to the transport operation of the transport mechanism. Since this vibration is a factor that reduces the conveyance efficiency, various conveyance apparatuses that perform vibration suppression control for suppressing vibration generated by the conveyance operation have been proposed.

  As an example of this type of transport apparatus, Patent Document 1 discloses a transport mechanism such as a gantry loader that performs a transport operation by inputting a drive command, and generates a drive command and inputs the drive command to the transport mechanism. A transport control unit that controls the transport of the object, and generates a drive command with a suppression command for suppressing vibrations caused by the desired transport operation when the transport mechanism performs a desired transport operation. A conveyance device that realizes vibration suppression by inputting the drive command to the conveyance mechanism is disclosed. This vibration suppression control is a control called anti-phase input control (Preshaping control), and in order to generate a drive command with a suppression command for vibration suppression, a part of the vibration characteristics of the conveyor device identified in advance. The natural frequency and attenuation coefficient are used.

  The damping coefficient, which is one of the vibration characteristics used in the above vibration suppression control, is the theoretical vibration calculated by the actual vibration detected by the vibration sensor and the vibration model by detecting the vibration generated by the transfer operation of the transfer device with the vibration sensor. Are generally identified by calculating the damping coefficient parameter of the vibration model so that both vibrations are fitted.

JP 2008-202719 A

  However, when the actual vibration detected by the vibration sensor has a plurality of vibration modes, the actual vibration and the theoretical vibration are the sum of all vibration modes, respectively, and the damping coefficient to be identified is also present for each vibration mode. In the fitting of vibration and theoretical vibration, it is conceivable that the identification of the damping coefficient of a certain vibration mode is influenced by other vibration modes, and the time required for identification increases and the identification accuracy is impaired.

  In particular, when vibration characteristics are identified by the simplex method from the fitting of actual and theoretical vibrations, the damping coefficient parameters and gain parameters used in the vibration model are repeatedly calculated so that the sum of the differences between actual and theoretical vibrations is reduced. Therefore, the time required for identification is significantly increased by iterative calculation. In addition, the actual vibration noise that does not exist in the theoretical vibration affects the sum of the differences, and the identification is caused by the influence of other parameters such as gain parameters. The accuracy is significantly impaired.

  The present invention has been made paying attention to such problems, the purpose of which is to reduce or eliminate the influence caused by the vibration generated by the transport operation of the transport device having a plurality of vibration modes, By providing a vibration characteristic identification device and vibration characteristic identification method for conveyors that have shortened the time required to identify vibration characteristics and improved identification accuracy, and by providing a conveyor and a conveyance system with improved vibration suppression. is there.

  In order to achieve this object, the present invention takes the following measures.

  In other words, the vibration characteristic identification device for a transfer device according to the present invention is a device for identifying the vibration characteristics of a transfer device, the vibration sensor detecting vibrations generated by the transfer operation of the transfer device, and the vibration sensor. Detected by the vibration sensor using a natural frequency specifying unit that specifies, for each vibration mode, a natural frequency that is one of the vibration characteristics based on vibration, and each natural frequency specified by the natural frequency specifying unit. A vibration separation unit that separates vibrations for each vibration mode, a damping coefficient that is one of the vibration characteristics based on the vibration separated by the vibration separation unit and the natural frequency specified by the natural frequency specifying unit. And a damping coefficient specifying unit that specifies each vibration mode.

  The natural frequency may be expressed in the form of a natural angular frequency, a natural frequency, or a period. Similarly, the attenuation coefficient may be expressed in other forms such as an attenuation constant and an attenuation force.

  According to this configuration, the natural frequency is specified for each vibration mode based on the vibration detected by the vibration sensor, and the vibration detected by the vibration sensor using the specified natural frequency is separated and separated for each vibration mode. Since the damping coefficient is specified for each vibration mode based on the vibration and the specified natural frequency, it is not affected by other vibration modes when specifying the damping coefficient of a certain vibration mode, and the time required for identification is reduced. Shortening and improvement of identification accuracy can be achieved.

  In order to significantly reduce the time required for identification by uniquely specifying the damping coefficient and to significantly improve the identification accuracy, the damping coefficient specifying unit uses the natural frequency of the vibration separated by the vibration separating unit. It is preferable to specify the attenuation coefficient based on the maximum amplitude appearing at each corresponding predetermined period.

  A conveyance system according to the present invention includes the above-described vibration characteristic identification device, a conveyance device that conveys an object to be conveyed, and an identification instruction that causes the identification device and the conveyance device to perform operations necessary to identify the vibration characteristics. And a conveying operation for conveying the object to be conveyed by input of a drive command, and a memory for storing the natural frequency and the damping coefficient identified by the vibration characteristic identification device. In order to cause the transport mechanism to perform a desired transport operation, a drive command accompanied by a suppression command for suppressing vibration generated by the desired transport operation is stored in the memory with the natural frequency and A transfer control unit configured to generate a drive command generated based on the attenuation coefficient and input the generated drive command to the transfer mechanism. Causing the conveying device to perform a predetermined identifying conveying operation at a predetermined timing, and causing the vibration characteristic identifying device to identify the natural frequency and the damping coefficient based on vibration generated by the identifying conveying operation, The result is stored in the memory.

  Examples of the predetermined timing include a factory shipment time and a predetermined time. The identification transport operation is a predetermined transport operation that generates vibration, and includes, for example, one that does not involve vibration suppression control.

  According to this transport system, the transport device generates a drive command with a command for suppressing vibration caused by a desired transport operation using the natural frequency and the attenuation coefficient stored in the memory, and generates the generated drive command. Is input to the transport mechanism to perform a desired transport operation with vibration suppression. In this case, the transport mechanism of the transport device performs the transport operation for identification at a predetermined timing such as when a predetermined time elapses, and the vibration characteristic identification device performs vibration characteristics based on the vibration generated by the transport operation for identification. Since the natural frequency and attenuation coefficient are identified and the identification result is stored in the memory, the vibration characteristics used for the conveyance control can be identified without manual operation. For example, even if the vibration characteristics change due to aging deterioration, Appropriate conveyance control using vibration characteristics can be realized. Furthermore, in order to identify vibration characteristics automatically at a predetermined timing such as at the time of initial processing when the power is turned on in the transport system, it is particularly required that the time required for identification is short, but the conventional identification device requires identification. Automation was difficult due to the time required. However, in the present embodiment, the time required for identifying the vibration characteristics is remarkably shortened by using the above identification device, so that the identification of the vibration characteristics is particularly suitable for automation, and conveyance using appropriate vibration characteristics is performed. It will contribute to the realization of control.

  A method for identifying vibration characteristics of a transfer apparatus according to the present invention is a method for identifying vibration characteristics of a transfer apparatus, the step of causing the transfer apparatus to perform a transfer operation to generate vibration, and the generated vibration using a vibration sensor. A step of detecting, a step of specifying a natural frequency, which is one of the vibration characteristics, for each vibration mode based on the detected vibration, and a vibration detected using each of the specified natural frequencies is separated for each vibration mode. And a step of specifying, for each vibration mode, a damping coefficient which is one of the vibration characteristics based on the separated vibration and the identified natural frequency.

  The natural frequency may be expressed in the form of a natural angular frequency, a natural frequency, or a period. Similarly, the attenuation coefficient may be expressed in the form of an attenuation constant, an attenuation force, or the like.

  According to this method, the natural frequency is specified for each vibration mode based on the vibration detected by the vibration sensor, and the vibration detected by the vibration sensor using the specified natural frequency is separated and separated for each vibration mode. Since the damping coefficient is specified for each vibration mode based on the vibration and the specified natural frequency, it is not affected by other vibration modes when specifying the damping coefficient of a certain vibration mode, and the time required for identification is reduced. In some cases, shortening and improvement of identification accuracy can be achieved.

  In order to remarkably reduce the time required for identification by uniquely specifying a damping coefficient and to significantly improve identification accuracy, the step of specifying the damping coefficient includes a predetermined frequency corresponding to the specified natural frequency among the separated vibrations. It is preferable that the attenuation coefficient is specified based on the maximum amplitude that appears in each period.

  As described above, the present invention separates the vibration detected by the vibration sensor for each vibration mode and then specifies the damping coefficient for each vibration mode. Therefore, when specifying the damping coefficient for a certain vibration mode, other vibration modes are used. It is possible to reduce the time required for identification and improve the identification accuracy.

The block diagram which shows typically the identification apparatus which identifies the vibration characteristic of the conveying apparatus which concerns on this invention. The power spectrum figure obtained when the detected vibration carries out FFT analysis. Explanatory drawing regarding isolate | separating the detected vibration into the vibration for every vibration mode. Explanatory drawing regarding specifying a damping coefficient based on the isolate | separated vibration. Explanatory drawing regarding specifying a damping coefficient based on the isolate | separated vibration. The flowchart which shows the vibration analysis process routine performed with the analysis processor of an identification device. The comparison figure which shows the result of having performed vibration suppression control using the vibration characteristic identified by the identification apparatus which concerns on this embodiment, and the conventional identification apparatus. The block diagram which shows typically the conveyance system which concerns on this invention. The flowchart which shows operation | movement of the conveyance system.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, the vibration characteristic identification device according to the present embodiment will be described, and then a conveyance system including the vibration characteristic identification device will be described.

<Vibration device vibration characteristic identification device>
In the transfer device 103 that transfers a transfer object W such as a wafer by driving a transfer mechanism 131 such as a robot arm as shown in FIG. 1, vibration may occur due to the transfer operation of the transfer mechanism 131. The vibration characteristic identification device 2 of the transfer device according to the present embodiment is a device that identifies the vibration characteristic of the transfer device 103 based on the vibration generated by the transfer operation, and detects the vibration generated by the transfer operation of the transfer device 103. A vibration sensor 21 and vibration analysis means 22 for identifying vibration characteristics based on the vibration detected by the vibration sensor 21 are provided. The identified vibration characteristics are parameters used for vibration suppression control performed by the transport device 103 to suppress vibration.

  The vibration sensor 21 is a sensor that detects the vibration of the transport mechanism 131 during the transport operation and the vibration remaining in the transport mechanism 131 after the transport operation is completed. Specifically, the vibration sensor 21 is an object to be transported among the robot arms serving as the transport mechanism 131. This is an acceleration sensor attached to a portion (arm tip) holding W or in the vicinity thereof. Of course, a displacement detecting means such as a laser displacement meter is arranged in a non-contact state with the arm in the vicinity of a portion (arm tip) of the arm that holds the conveyance target W so that residual vibration is detected by the displacement detecting means. It may be. The position where the vibration sensor 21 is provided is not limited to the position described above, and is limited to the acceleration sensor and the displacement meter described above as long as the vibration of the conveyance mechanism to be controlled can be detected. It is not a thing.

  The vibration analysis unit 22 includes a natural frequency specifying unit 23, a vibration separating unit 24, and a damping coefficient specifying unit 25. These units 23, 24, and 25 execute software and hardware by executing a vibration analysis processing routine shown in FIG. 6 stored in advance by the CPU in an information processing apparatus such as a personal computer having a CPU, ROM, various interfaces, and the like. Is realized through collaboration.

The natural frequency specifying unit 23 in FIG. 1 specifies a natural frequency, which is one of the vibration characteristics, for each vibration mode based on the vibration detected by the vibration sensor 21. Specifically, the vibration is detected by the vibration sensor 21 (process S1 in FIG. 6), and the power spectrum shown in FIG. 2 is obtained by performing FFT analysis on the detected vibration, and the power spectrum is specific to each vibration mode based on this power spectrum. The frequency is specified (process S2 in FIG. 6). In the example shown in FIG. 2, the natural frequency specifying unit 23 has a natural angular frequency ω ₁ corresponding to the natural frequency of the primary vibration mode, a natural angular frequency ω ₂ corresponding to the natural frequency of the secondary vibration mode, and the natural frequency of the tertiary vibration mode. It appears as a natural angular frequency ω ₃ corresponding to the frequency, and when the detected vibration has three vibration modes, it is specified through the above natural angular frequencies ω _1, ω _{2 and} ω ₃ .

）で除去することにより行う（図６の処理Ｓ３）。図３に示す例は、振動センサで検出された振動ｙ（ｔ）から分離した一次振動モードの振動ｙ_１（ｔ）及び二次振動モードの振動ｙ_２（ｔ）を示している。各振動は次式で表される。
振動センサで検出された振動Ｖｉ：

一次振動モードの振動Ｖｉ_１：

二次振動モードの振動Ｖｉ_２：

なお、本実施形態ではノッチフィルタを用いているが、これに限定されず、例えばバンドパスフィルタ等の他のフィルタリングを用いて振動モード毎に分離してもよく、さらに他の方法により振動モード毎に分離してもよい。 As shown in FIG. 3, the vibration separating unit 24 of FIG. 1 uses the natural angular frequencies ω ₁ , ω ₂ , and ω ₃ corresponding to the natural frequencies specified by the natural frequency specifying unit 23, and the vibration sensor 21. The detected vibration Vi is separated for each vibration mode. Specifically, using the natural angular frequencies ω ₁ , ω ₂ , and ω ₃ corresponding to the natural frequencies obtained for each vibration mode, vibrations in vibration modes other than the vibration mode to be extracted are notched (for example,

) To remove (step S3 in FIG. 6). The example shown in FIG. 3 shows the vibration y ₁ (t) in the primary vibration mode and the vibration y ₂ (t) in the secondary vibration mode separated from the vibration y (t) detected by the vibration sensor. Each vibration is expressed by the following equation.
Vibration Vi detected by vibration sensor:

Vibration Vi _{1 in} primary vibration mode:

Vibration Vi _{2 in} secondary vibration mode:

In this embodiment, the notch filter is used. However, the present invention is not limited to this. For example, the filter may be separated for each vibration mode by using other filtering such as a band pass filter, and may be separated for each vibration mode by other methods. May be separated.

As shown in FIG. 4A, the damping coefficient specifying unit 25 in FIG. 1 has the vibration Vi _K (k is the order of the vibration mode) separated into each vibration mode by the vibration separating unit 24 with the maximum amplitude for each half cycle. a _{1, a} 2, ..., by utilizing the fact that having _{a N,} a plurality of maximum amplitude _a 1 is these _scalars, a _{2, ...,} vibration which is one damping coefficient of the vibration characteristics on the basis of the _{a N} This is specified for each mode. The maximum amplitude is the absolute value of the waveform size.

Specifically, as shown in FIG. 4B, the damping coefficient specifying unit 25 in FIG. 1 performs absolute value processing on the separated vibration Vi _K to convert it into only positive vibration (processing in FIG. 6). S4) Of the converted vibration waveforms, the magnitude of the waveform at the time when the vibration changes from the increasing direction to the decreasing direction is set as the maximum amplitude A, and the maximum amplitude A is obtained every half cycle (process S5 in FIG. 6). And these maximum amplitude A _1, A 2, _..., by paying attention to A _N is attenuated gradually to identify the damping coefficient. Further, in specifying the attenuation coefficient based on the maximum amplitudes A ₁ , A ₂ ,..., A _N , the entire amplitude is expressed by drawing a function whose maximum amplitude A is mainly exp (−ζωt). By using a natural logarithm, an exponential function that increases the amount of calculation is avoided. In this case, by transforming the entire equation as a natural logarithm, the following equation composed of the natural angular frequency ω corresponding to the slope a of the straight line and the natural frequency is derived.
Damping coefficient ζ:

As shown in FIG. 5, it is to be a straight line Li, a plurality of maximum amplitude _{A 1,} A 2, ..., the value of each was _{A N} to the natural logarithm _{ln (A 1), ln (} A 2), ..., ln A straight line that best fits (A _N ), and this straight line Li is calculated by the method of least squares (processing S6 to S9 in FIG. 6).

  In the present embodiment, the maximum amplitude A that appears in each half cycle corresponding to the natural frequency among the separated vibrations is used. However, the maximum amplitude A is not limited to a half cycle as long as the cycle corresponds to the natural frequency. . For example, it may be every one cycle or every two cycles.

  In the vibration characteristic identification device using the conventional simplex method, for example, it took 10 minutes or more to identify the damping coefficient ζ. However, when the vibration characteristic identification device described above is used, like the conventional simplex method, Since iterative calculation is not performed, the time required for identification of the attenuation coefficient ζ can be made within one second under the same conditions. Of course, the time required for the identification described above varies depending on the environment, which is an example. In some environments, the time required to calculate the attenuation coefficient ζ can be reduced by several thousandths compared to the conventional case. did it.

Further, a simulation is performed by using the well-known transfer device 103 that performs vibration suppression control as shown in FIG. 1 using the natural frequency and damping coefficient identified by the conventional vibration characteristic identification device and the vibration characteristic identification device 2 according to the present embodiment, respectively. The effect of vibration suppression was verified. The result is shown in FIG. FIG. 7A shows the result of simulation using the natural frequency and the attenuation coefficient identified by the identification device using the conventional simplex method, and the figure shows the vibration amount after completion of conveyance. In this result, although the target vibration suppression state (for example, 50 μm or less) has been reached in t ₁ seconds after the completion of the transport operation, there is residual vibration due to the influence of the attenuation coefficient error.

On the other hand, FIG. 7B shows the result of simulation using the natural frequency and attenuation coefficient identified by the identification apparatus according to the present embodiment, and the figure shows the vibration amount after the end of conveyance. In this result, although there is residual vibration that is considered to be the influence of the sampling time, the target vibration suppression state (for example, 50 μm or less) is reached in t ₂ seconds (t ₂ <t ₁ ) after the completion of the transport operation. . In addition, since the target vibration suppression state is detected at the same time as the residual vibration is detected, it is considered that the target vibration suppression state has been reached at the same time as the transfer operation is completed. It can be seen that the accuracy is improved.

<Transport system>
Next, the conveyance system 1 provided with said vibration characteristic identification apparatus 2 is demonstrated with reference to drawings.

  As shown in FIG. 8, the transport system 1 of this embodiment includes a transport device 3 and the identification device 2 that identifies the vibration characteristics of the transport device 3.

  The transport device 3 includes a memory 33 that stores a natural frequency and a damping coefficient that are part of vibration characteristics, a transport mechanism 31 such as a robot arm that performs a transport operation for transporting a transport object in response to input of a drive command, and a drive command. And a transport control means 32 for controlling the transport by inputting it into the transport mechanism. In the present embodiment, the memory 33 is included in the transport control unit 32, but the present invention is not limited to this.

  The transport control unit 32 generates a target command gRef for generating a target command gRef for causing the transport mechanism 31 to perform a desired transport operation, and a drive command in which a suppression command bRef is added to the target command gRef generated by the target command generation unit 32a. and a drive command generation unit 32 b that generates drRef based on the natural frequency and the attenuation coefficient stored in the memory 33. The suppression command bRef is a command for suppressing vibration caused by a desired transport operation. Preshaping control that generates a drive command drRef accompanied by such a suppression command bRef and controls the driving of the transport mechanism 31 using the generated drive command drRef is a well-known control, and thus detailed description thereof is omitted.

  The identification device 2 has substantially the same configuration as described above, and detects the vibration generated by the transport operation of the transport device 3 to identify the natural frequency and the damping coefficient that are the vibration characteristics.

  In the present embodiment, in addition to the above configuration, the following configuration is further added.

  That is, identification instruction means 4 is provided for causing the transport device 3 and the identification device 2 to perform operations necessary for identifying the vibration characteristics. The identification instructing means 4 causes the transport device 3 to perform a transport operation for identification at a predetermined timing such as during an initialization process performed when the power of the transport system 1 is turned on, and based on vibrations generated by the transport operation for identification. The natural frequency and the attenuation coefficient are identified by the identification device 2, and the identification result is stored in the memory 33. Specifically, as shown in FIGS. 8 and 9, the identification instruction unit 4 determines whether or not it is a predetermined timing (process ST <b> 1 in FIG. 9). In addition, an identification conveyance operation instruction is given to the identification apparatus 2 and an identification start instruction is given to the identification apparatus 2 (process ST2 in FIG. 9). Receiving the identification transport operation instruction, the transport device 3 causes the transport mechanism 31 to perform the transport operation for identification stored in advance in the memory 33 (process ST3 in FIG. 9). Upon receiving the identification start instruction, the identification device 2 detects the vibration generated by the identification carrying operation performed in the process ST3 in FIG. 9 by the vibration sensor 21 (process ST4 in FIG. 9), and is unique based on the detected vibration. The natural angular frequency and the attenuation coefficient corresponding to the frequency are identified, and the identification result is transmitted to the transport device (process ST5 in FIG. 9). Receiving the identification result, the transfer device 3 stores the identification result in the memory 33 (process ST6 in FIG. 9).

  The identification conveyance operation may be any conveyance operation that generates vibration, and examples thereof include an operation that does not involve vibration suppression using a natural frequency and a damping coefficient that are part of the vibration characteristics. The predetermined timing includes, for example, when the initial process is executed when the power is turned on, at the time of factory shipment, or when a predetermined time elapses.

As described above, the vibration characteristic identification device 2 of the transfer device according to the present embodiment is a device that identifies the vibration characteristics of the transfer devices 3 and 103 and detects the vibration Vi generated by the transfer operation of the transfer devices 3 and 103. The natural frequency identification that identifies the natural angular frequencies ω ₁ , ω ₂ , and ω ₃ corresponding to the natural frequency that is one of the vibration characteristics based on the vibration Vi and the vibration Vi detected by the vibration sensor 21 for each vibration mode. A vibration separating unit 24 that separates the vibration Vi detected by the vibration sensor 21 using each of the natural frequencies ω ₁ , ω ₂ , and ω ₃ specified by the natural frequency specifying unit 23 for each vibration mode; vibration _Vi 1 separated by vibration isolation unit _24, Vi _2, Vi ₃ and the natural angular frequency omega ₁ corresponding to the natural frequency identified by a unique frequency identification unit 23, ω _2, ω ₃ and based on There are and a damping coefficient specifying unit 25 for specifying a ζ is one damping coefficient of the vibration characteristic in the vibration mode each.

As described above, the natural angular frequencies ω ₁ , ω ₂ , and ω ₃ corresponding to the natural frequencies are specified for each vibration mode based on the vibration Vi detected by the vibration sensor 21, and the natural angular frequencies corresponding to the specified natural frequencies. The vibration Vi detected by the vibration sensor 21 using ω ₁ , ω ₂ , and ω ₃ is separated for each vibration mode, and the natural angle corresponding to the natural frequencies identified as the separated vibrations Vi ₁ , Vi ₂ , and Vi _3. Since the damping coefficient ζ is specified for each vibration mode based on the frequencies ω ₁ , ω ₂ , and ω ₃ , the vibration coefficient is not affected by other vibration modes when specifying the damping coefficient ζ of a certain vibration mode. In some cases, it is possible to shorten the time required for the process and improve the identification accuracy.

Conventionally, the simplex method is used to specify the damping coefficient that is one of the vibration characteristics, and the actual vibration detected by the vibration sensor is compared with the theoretical vibration calculated by the vibration model to reduce the difference between both vibrations. In this embodiment, the damping coefficient parameter and gain parameter used in the vibration model are repeatedly calculated, and the time required for identification increases due to the repeated calculation. Focusing on the fact that the vibrations Vi ₁ , Vi ₂ , and Vi ₃ have the maximum amplitude A every half cycle (every predetermined cycle) corresponding to the natural frequency, the damping coefficient ζ is specified based on each maximum amplitude A Therefore, the attenuation coefficient ζ can be uniquely identified from the maximum amplitude A that is attenuated every half cycle (every predetermined cycle), and iterative calculation as in the conventional simplex method. As required, it is possible to significantly shorten the time required for the identification.

  In addition, in this embodiment, other parameters such as gain parameters used in the conventional simplex method do not affect the identification accuracy, and errors are not enlarged by repeated calculation, so that the identification accuracy can be significantly improved. It becomes possible.

  Furthermore, in the conventional simplex method, the actual vibration to be compared and the theoretical vibration calculated by the vibration model are shown as waveforms, and it is difficult to match the offset and phase of both vibration waveforms, and these mismatches become errors. However, in this embodiment, since a plurality of maximum amplitudes A that are scalars are used, the time required for identification is prevented by preventing the occurrence of such inconvenience. It is thought that it contributes to shortening and improvement of identification accuracy.

  The transport system 1 according to the present embodiment performs the operations necessary for identifying the vibration characteristics with respect to the vibration characteristic identification device 2, the transport device 3 that transports the transport target W, and the identification device 2 and the transport device 3. Identification instruction means 4 to be performed, and the conveying device 3 stores a memory 33 for storing a natural angular frequency ω and a damping coefficient ζ corresponding to the natural frequency identified by the vibration characteristic identifying device 2, and a drive command drRef. When the transport mechanism 31 performs a transport operation for transporting the transport object W by the input, and the transport mechanism 31 performs a desired transport operation, a suppression command bRef for suppressing vibrations caused by the desired transport operation is accompanied. The transport control hand that generates the drive command drRef based on the natural angular frequency ω and the damping coefficient ζ corresponding to the natural frequency stored in the memory 33 and inputs the generated drive command drRef to the transport mechanism 31. 32, the identification instructing means 4 causes the conveyance device 3 to perform a predetermined identification conveyance operation at a predetermined timing, and the natural frequency based on the vibration generated by the identification conveyance operation. The vibration characteristic identification device 2 identifies the natural angular frequency ω and the damping coefficient ζ corresponding to, and the identification result is stored in the memory 33.

  In this way, the drive command drRef accompanied by a command for the transport device 3 to suppress vibration caused by a desired transport operation using the natural angular frequency ω and the damping coefficient ζ corresponding to the natural frequency stored in the memory 33. And the generated drive command drRef is input to the transport mechanism 31 to perform a desired transport operation with vibration suppression. In this case, the transport mechanism 31 of the transport device 3 performs the transport operation for identification at a predetermined timing such as when a predetermined time elapses, and the vibration characteristic identification device 2 is based on the vibration generated by the transport operation for identification. Thus, the natural angular frequency ω and the damping coefficient ζ corresponding to the natural frequency which is the vibration characteristic are identified, and the identification result is stored in the memory 33. Therefore, the vibration characteristic used for the conveyance control can be identified without relying on manual operation. Even when the vibration characteristics change due to this, it is possible to realize appropriate transport control using the changed vibration characteristics.

  Furthermore, in order to identify vibration characteristics automatically at a predetermined timing such as at the time of initial processing when the power is turned on in the transport system 1, it is particularly required that the time required for the identification is short. Automation was difficult due to the time required. However, in the present embodiment, since the time required for identifying the vibration characteristics is remarkably shortened using the identification device 2, the identification of the vibration characteristics is particularly suitable for automation, and appropriate vibration characteristics are used. This will contribute to the realization of transport control.

The method for identifying vibration characteristics of a transfer apparatus according to the present embodiment is a method for identifying the vibration characteristics of the transfer apparatus. The method includes causing the transfer apparatuses 3 and 103 to perform a transfer operation to generate vibration, The step of detecting by the vibration sensor 21, the step of specifying the natural angular frequency ω corresponding to the natural frequency which is one of the vibration characteristics based on the detected vibration for each vibration mode, and the corresponding natural frequency natural angular frequency omega ₁ corresponding to the natural frequency identified the steps of the detected vibration to separate the vibrational mode each, and the vibration Vi _1, Vi _2, Vi ₃ was separated using natural angular frequency _omega, omega _2, omega ₃ And specifying a damping coefficient ζ, which is one of the vibration characteristics, for each vibration mode based on the above.

  The natural frequency may be expressed in the form of a natural angular frequency, a natural frequency, or a period. Similarly, the attenuation coefficient may be expressed in the form of an attenuation constant, an attenuation force, or the like.

According to this method, the natural angular frequency ω corresponding to the natural frequency is specified for each vibration mode based on the vibration detected by the vibration sensor 21, and the vibration sensor is used using the natural angular frequency ω corresponding to the specified natural frequency. The vibration detected in 21 is separated for each vibration mode, and the vibration is based on the separated vibrations Vi ₁ , Vi ₂ , Vi ₃ and the natural angular frequencies ω ₁ , ω ₂ , ω ₃ corresponding to the identified natural frequencies. Since the damping coefficient ζ is specified for each mode, it is not affected by other vibration modes when specifying the damping coefficient ζ of a certain vibration mode, and the time required for identification can be shortened and the identification accuracy can be improved. There are cases where it is possible.

  In the present embodiment, the step of specifying the damping coefficient ζ is to specify the damping coefficient ζ based on the maximum amplitude that appears at every predetermined period corresponding to the specified natural frequency among the separated vibrations. As described above, it is possible to significantly reduce the time required for identification by uniquely specifying the attenuation coefficient and to significantly improve the identification accuracy.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not only by the above description of the embodiments but also by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the present embodiment, the identification instruction unit 4 is realized by executing the identification instruction program by the processor of the identification device 2. However, the identification instruction unit 4 is executed by the transport device 3 or other processors. You may comprise so that it may implement | achieve. 1 and FIG. 8 is realized by executing a predetermined program by a processor, but each functional unit may be configured by a dedicated circuit.

  Finally, the specific configuration of each part is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Conveyance system 2 ... Vibration characteristic identification apparatus 21 ... Vibration sensor 23 ... Natural frequency specific | specification part 24 ... Vibration isolation | separation part 25 ... Damping coefficient specific | specification part 3, 103 ... Conveyance apparatus 31 ... Conveyance mechanism 32 ... Conveyance control means 33 ... Memory 4 ... identification instruction means ζ ... damping coefficient ω ... natural frequency (natural angular frequency)

Claims (5)

An apparatus for identifying the vibration characteristics of a transfer device,
A vibration sensor for detecting vibrations generated by a transport operation of the transport device;
A natural frequency specifying unit for specifying a natural frequency that is one of the vibration characteristics for each vibration mode based on vibration detected by the vibration sensor;
A vibration separating unit that separates the vibration detected by the vibration sensor for each vibration mode using each natural frequency specified by the natural frequency specifying unit;
A damping coefficient specifying unit that specifies, for each vibration mode, a damping coefficient that is one of the vibration characteristics based on the vibration separated by the vibration separating unit and the natural frequency specified by the natural frequency specifying unit; An apparatus for identifying vibration characteristics of a conveying device.   2. The vibration characteristic identification device according to claim 1, wherein the damping coefficient specifying unit specifies the damping coefficient based on a maximum amplitude appearing at a predetermined period corresponding to the natural frequency among vibrations separated by the vibration separating unit. . The vibration characteristic identification device according to claim 1 or 2,
A transport device for transporting a transport object;
An identification instruction means for causing the identification device and the transfer device to perform an operation necessary for identification of the vibration characteristics,
The transfer device
A memory for storing the natural frequency and the damping coefficient identified by the vibration characteristic identification device;
A transport mechanism for performing a transport operation for transporting the transport object in response to an input of a drive command;
When causing the transport mechanism to perform a desired transport operation, a drive command accompanied by a suppression command for suppressing vibration caused by the desired transport operation is based on the natural frequency and the attenuation coefficient stored in the memory. And a transport control means for inputting the generated drive command to the transport mechanism,
The identification instructing unit causes the transport device to perform a predetermined identification transport operation at a predetermined timing, and determines the natural frequency and the attenuation coefficient based on the vibration generated by the transport operation for identification. A transport system for causing an identification device to identify and storing an identification result in the memory. A method for identifying vibration characteristics of a conveying device,
Causing the transfer device to perform a transfer operation to generate vibration;
Detecting the generated vibration with a vibration sensor;
Identifying a natural frequency that is one of the vibration characteristics based on the detected vibration for each vibration mode;
Separating the vibration detected using each identified natural frequency for each vibration mode;
A vibration characteristic identification method for a conveying apparatus, comprising: specifying a damping coefficient, which is one of the vibration characteristics, for each vibration mode based on the separated vibration and the identified natural frequency. 5. The vibration of the transfer device according to claim 4, wherein the step of specifying the damping coefficient specifies the damping coefficient based on a maximum amplitude appearing every predetermined period corresponding to the specified natural frequency among the separated vibrations. Characteristic identification method.

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