JP4705653B2 - Vibration control device - Google Patents

Description

  The present invention relates to a vibration damping device, and more particularly to a vibration damping device that is effective when vibration having a frequency different from a resonance frequency occurs in a building, a facility, or the like.

Among vibration damping devices for structural vibrations, devices for natural vibration have been proposed as various types and types as general vibration damping devices. For example, TMD (Tuned Mass Damper) and active devices that apply control force to it are put into practical use and commercialized.
The structural vibration damping device that is widely put into practical use produces an effect equivalent to reducing the resonance magnification in the structural vibration characteristics by vibrating the device in synchronization with the natural vibration of the target structure. On the other hand, a structural vibration damping device that has been put into practical use is not effective for forced vibrations that deviate from the natural frequency.

Thus, for example, Patent Document 1 proposes a damping device for forced vibration.
Patent Document 1 discloses that when a vibration control device installed in the vicinity of a vibration source activates a vibration sensor, a phase extraction unit, and a frequency extraction unit, the phase extraction unit and the phase extraction unit are detected from the vibration of the vibration source detected by the vibration sensor. The frequency extraction means extracts the phase and frequency of the vibration. And the frequency and phase of a shaker are adjusted by the action | operation of a control apparatus, and a shaker is operated. Since the vibration exciter is attached to the vibration system, the vibration is transmitted to the vibration system by the operation of the vibration exciter, and the mass element is vibrated in the vertical direction.
In Patent Document 1, the resonance frequency of the vibration system is set within the approximate range of the vibration frequency of the vibration source on the assumption that the vibration frequency of the vibration source is limited to a predetermined range. When the frequency approaches the resonance frequency of the vibration system, the vibration system vibrates greatly and generates a large excitation force (inertial force) that matches the vibration frequency of the shaker. The vibration of the vibration exciter is the same as the vibration frequency of the vibration source, and the vibration of the vibration source and the vibration of the vibration system are adjusted to have opposite phases. It is added to the installation surface with the opposite phase to the vibration. As a result, it is possible to generate a large excitation force by greatly vibrating the vibration system with a relatively small excitation force generated by the vibration exciter. Propagation will be prevented.

JP 2005-221054 A

In the vibration damping device of Patent Document 1, the natural frequency is matched with the vibration frequency of the vibration source. For this reason, the natural vibration of the vibration system does not have an opposite phase with respect to the forced vibration. However, although Patent Document 1 vibrates while adjusting the phase, since it is not easy to accurately control the phase opposite to the vibration of the vibration source, a sufficient damping effect may not be obtained. .
The present invention has been made based on such a technical problem, and an object of the present invention is to provide a vibration damping device capable of reducing forced vibration without performing phase control.

In referring to the present invention, a damping mechanism for the natural vibration of a structure will be described with reference to FIG.
As shown in the upper part of FIG. 1, when a disturbance having a natural frequency of a structure is input and a countermeasure device having the same natural frequency as the natural frequency of the structure is installed, the structure is shaken by the disturbance. Since this vibration is resonant, the phase is delayed by 90 °, and the structure response displacement is delayed by 90 ° with respect to the disturbance as shown in the middle part of FIG. At this time, the structure response acceleration advances by 180 ° with respect to the structure response displacement. When the structure response acceleration is α, it can be considered that an inertial force of −mα is applied to a countermeasure device that is installed on the structure and is shaken when the structure is shaken. Here, m is the mass of the countermeasure device movable vibrator.
Since the countermeasure device for the natural vibration is adjusted to have the same natural frequency as the structure natural frequency, the response displacement of the countermeasure device is 90 ° with respect to −mα when a force of −mα is applied. Delayed (lower part of Fig. 1). At this time, the countermeasure device response acceleration advances by 180 ° with respect to the countermeasure device response displacement.
Since the countermeasure device moves by 90 ° behind the structure response, it acts as a structure damping effect. Alternatively, when the way of thinking is changed, a device inertia force −mβ (where β is a response device response acceleration) generated by the response acceleration of the countermeasure device is input to the structure, and the disturbance is canceled by the device inertia force.

  Next, as shown in the upper part of FIG. 2, when a disturbance other than the natural frequency of the structure is input, the structure is shaken at the same frequency as the forced frequency. Since this fluctuation is not resonance, the phase delay of the structure response displacement with respect to the disturbance is not 90 ° as shown in the middle part of FIG. And a countermeasure apparatus is shaken with the shake of a structure. When the natural frequency of the countermeasure device is made to coincide with the vibration frequency of the vibration source as in Patent Document 1, this vibration becomes resonance, and the phase of the countermeasure device response displacement is delayed by 90 ° from the structure response. Since the countermeasure device moves 90 ° behind the structure response, it works as a structure damping effect.

  FIG. 3 is a diagram showing the concept of the present invention. The upper and middle graphs are the same as in FIG. In other words, even in the present invention, when a disturbance other than the natural frequency of the structure is input, the structure is shaken at the same frequency as the forced frequency, but since this fluctuation is not a resonance, the phase of the structure response displacement The delay is not 90 °, for example, 45 °. In the present invention, the natural frequency of the countermeasure device is adjusted so that the phase delay of the countermeasure device with respect to the structure response is 135 °. If it does so, the phase delay of the countermeasure apparatus with respect to a disturbance will be 180 degrees. As a result, the countermeasure device response moves with a 180 ° delay with respect to the disturbance. Since the countermeasure device response displacement is the same movement as the countermeasure force applied to the structure, the effect of canceling the disturbance is exhibited by the movement of the countermeasure device.

That is, the vibration damping device of the present invention is a device that is disposed in the vicinity of a target structure to which forced vibration is applied and that suppresses vibration generated in the target structure, and is a vibrating body that is allowed to be displaced in a predetermined direction. And a controller for controlling the operation of the driving means so as to suppress the vibration of the target structure due to the forced vibration, and the vibrating body is based on the phase of the forced vibration. The characteristic frequency is set such that the phase of vibration of the vibrating body due to forced vibration is delayed within a range of 180 ° ± 10 °.
Even if the damping device of the present invention is in a state where the countermeasure device is not driven (passive state), the countermeasure device has a phase of vibration of the countermeasure device due to forced vibration of 180 ° ± 10 rather than the phase of forced vibration. Since its natural frequency is set so as to be delayed within a range of °, it has a function of canceling forced vibration. Actually, when the countermeasure device functions, it is only necessary to set conditions for amplifying the vibration of the countermeasure device without adjusting the phase.

  The vibration damping device of the present invention includes a sensor that detects vibration or displacement of the target structure or the countermeasure device, and the controller can control the driving unit based on information on the vibration or displacement. For example, the displacement of the target structure to which the forced vibration is applied is detected, the amplitude of the forced vibration is obtained from the information related to the displacement, and the countermeasure device is operated under the amplification conditions described above so that an amplitude matching the amplitude is obtained. If the vibrating body is driven, the vibration of the target structure due to forced vibration can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the damping device which can reduce forced vibration, without performing phase control is provided. Moreover, this vibration damping device can reduce forced vibration even in a passive state. When driving the vibration damping device, it is only necessary to set conditions for amplifying the vibration of the countermeasure device without adjusting the phase, so that the drive device can be controlled easily.

<First Embodiment>
Hereinafter, the present invention will be described in detail based on a first embodiment shown in FIGS.
The vibration damping device 10 according to the present embodiment is disposed close to a target structure (for example, a dome stadium, a concert hall) to which forced vibration is applied as a disturbance, and includes a countermeasure device 20, a controller 30, and a target. A structure vibration sensor 40a and a countermeasure device vibration sensor 40b are provided. In the present embodiment, it is assumed that the frequency of forced vibration as disturbance is known and constant. In the case of “vertical glue”, the frequency is 2 to 3 Hz.
The countermeasure device 20 includes a vibrating body 21 having a predetermined mass and a leaf spring 22 that defines the moving direction of the vibrating body 21 as components of the vibration system. One end of each leaf spring 22 is fixed to a pedestal 23 having a U-shaped cross section installed on the installation surface A. Further, the other end of each leaf spring 22 is fixed to the upper and lower ends of the vibrating body 21. Therefore, the vibrating body 21 can be displaced in the vertical (vertical) direction as indicated by an arrow in FIG. 4, but the displacement in the horizontal (horizontal) direction is restricted. Note that the natural frequency of the countermeasure device 20 can be adjusted by changing the number of leaf springs 22.

An actuator 25 is disposed between the gantry 23 and the vibrating body 21. The actuator 25 drives the vibrating body 21 in the vertical direction according to a command from the controller 30. The actuator 25 may be of any form as long as it drives the vibrating body 21 in the vertical direction. For example, a VCM (Voice Coil Motor) composed of a combination of an electromagnetic coil and a permanent magnet can be used.
A coil spring 24 is disposed between the gantry 23 and the vibrating body 21. The coil spring 24 supports the vibrating body 21 by being compressed by the weight of the vibrating body 21. When the vibrating body 21 is displaced in the vertical direction, a force corresponding to the amount of displacement is applied to the vibrating body 21.

  In the countermeasure device 20 as described above, the natural frequency of the vibrating body 21 is set so that the phase of the vibration of the vibrating body 21 due to the forced vibration is 180 ° behind the phase of the forced vibration. This can be adjusted by measuring the forced vibration applied to the target structure and adjusting the mass of the vibrating body 21 and the spring constant of the leaf spring 22 so as to obtain the natural frequency. In the present embodiment, an example of 180 ° is shown as the most preferable value of the phase delay. However, if the phase delay is in the range of 180 ° ± 10 °, the forced vibration is equivalent without performing phase control. The degree can be reduced. The phase delay is preferably in the range of 180 ° ± 3 °, more preferably in the range of 180 ° ± 3 °, and most preferably 180 °.

As shown in FIG. 5, the controller 30 includes an FFT (Fast Fourier Transform) unit 31 and a forced vibration countermeasure controller 32. As is well known, Fast Fourier Transform is an algorithm for calculating a discrete Fourier transform (DFT) at high speed on a computer.
The controller 30 obtains vibration information including the displacement and speed of the target structure from the target structure vibration sensor 40a installed in the target structure. This vibration information includes vibration information due to the vibration of the countermeasure device 20. In addition, the controller 30 obtains vibration information including the displacement and speed of the countermeasure device 20 from the countermeasure device vibration sensor 40 b installed in the countermeasure device 20.
The controller 30 can extract the forced vibration component and the natural vibration component by performing FFT processing on the vibration information acquired from the target structure vibration sensor 40a. Here, for the forced vibration component, a frequency having the largest response amplitude is extracted. In the present invention, this forced vibration component is defined as a main forced vibration component.

  FIG. 6 shows an example of the result of performing the FFT process. In FIG. 6, the frequency f1 corresponds to the main forced vibration component, and f2 corresponds to the natural vibration component. The f1 (main forced vibration component) and f2 (natural vibration component) themselves are known information obtained in advance for the target structure. As shown in FIG. 6, the response amplitude is A1 (m) and the response phase is B1 (deg) for the main forced vibration component, the response amplitude is A2 (m) and the response phase is B2 (deg) for the natural vibration component. ) Can be extracted by FFT processing. Here, f1 and f2 are shown as specific values, but in the present invention, f1 and f2 can be handled as frequency bands having a range.

  The forced vibration countermeasure controller 32 generates a control command for the countermeasure device 20 based on main forced vibration components obtained by the FFT processing. The controller 30 outputs the control command generated by the forced vibration countermeasure controller 32 toward the actuator 25 of the countermeasure device 20.

Next, the operation procedure of the vibration damping device 10 will be described with reference to FIG.
For example, when a vertical slack occurs in a concert, the controller 30 measures a response (vibration information) of the target structure via the target structure vibration sensor 40a (S101). Next, the controller 30 acquires vibration information from the target structure vibration sensor 40a, and the FFT unit 31 performs frequency analysis by performing FFT processing on the acquired vibration information (S103). This result is, for example, as shown in FIG.
The controller 30 refers to the result of the FFT process and extracts main forced vibration components (S105). The main forced vibration component is sent to the forced vibration countermeasure controller 32.

  The forced vibration countermeasure controller 32 specifies, for example, that the main forced vibration component has the frequency f1 (Hz), the amplitude is A1 (m), and the phase is B1 (deg) (S107). The forced vibration countermeasure controller 32 obtains a disturbance from this main forced vibration component by back calculation. The disturbance is, for example, “vertical glue” as described above. In order to obtain the disturbance by back calculation, the forced vibration countermeasure controller 32 holds, for example, a table of the form shown in FIG. The table shown in FIG. 8 describes the amplitude ratio (m / N) for each vibration frequency of the target structure. In FIG. 8, for example, when the frequency is f1, it means that the amplitude when a 1N disturbance is input is a1 (m). The amplitude ratio (m / N) for each vibration frequency of the target structure may be obtained in advance for the target structure by calculation and stored in the memory device of the forced vibration countermeasure controller 32.

The forced vibration countermeasure controller 32 specifies main forced vibration components (frequency: f1 (Hz), amplitude: A1 (m)) and then calculates the disturbance by referring back to the above-described table (S109). . When the main forced vibration component is frequency: f1 (Hz) and amplitude: A1 (m), the disturbance amplitude is obtained as A1 / a1 (N).
Next, the forced vibration countermeasure controller 32 sets a countermeasure force for canceling the disturbance obtained by the reverse calculation (S111). For this purpose, the forced vibration countermeasure controller 32 measures the behavior (displacement) of the countermeasure device 20 obtained by the countermeasure device vibration sensor 40b (S113), and amplifies the behavior so that the countermeasure force having the same amplitude as the disturbance amplitude is obtained. Ask for. Specifically, the forced vibration controller 32 sets the countermeasure force to, for example, frequency: f1 (Hz) and amplitude: β * A1 / a1 (N) by setting an arbitrary coefficient β. Β is set in the range of 0.0 to 1.0. 1.0 means that a countermeasure force for completely canceling the disturbance is given, and 0.0 means that a countermeasure force is not given. However, normally, when β is set to 1.0, there arises a problem of control stability, and a large motor power is required. Therefore, a value less than 1.0 is set.

  The controller 30 gives the set countermeasure force (β * A1 / a1 (N)) to the actuator 25. The actuator 25 is driven according to this countermeasure force. Here, the natural frequency of the vibrating body 21 is set so that the phase difference from the disturbance is 180 °. Therefore, even in a passive state where no control force is applied to the countermeasure device 20, the countermeasure device 20 works to reduce disturbance (forced vibration). If the amplitude as the countermeasure force is set to be the same as the amplitude of the forced vibration, the effect of canceling the disturbance can be exhibited and the swing of the target structure can be suppressed.

In the present embodiment, the countermeasure device 20 in the form of directly transmitting the force of the actuator 25 to the vibrating body 21 supported by the leaf spring 22 is shown, but the present invention is not limited to this. A device capable of applying vibration according to the countermeasure force described above can be applied. For example, the device shown in FIG. 1 of Patent Document 2 or the device shown in FIG. 1 of Patent Document 3 can be applied as the countermeasure device of the present invention. Moreover, the vibration system using the rotary mass body disclosed in Patent Document 1 can also be used. In this case, although it is necessary to accurately control the acceleration of the rotating mass body, there is an advantage that the vibrating body can be driven with a small force.
In the present embodiment, an example in which the vibrating body 21 is displaced in the vertical (vertical) direction has been described. However, the present invention is not limited to this, and any countermeasure device having a vibrating body that is displaced in the horizontal direction can be used. It can be applied to a countermeasure device having a vibrating body that is displaced in a direction that coincides with the vibration direction.

JP-A-2-296975 JP-A-6-288119

<Second Embodiment>
In the vibration damping device 10 of the first embodiment, the vibration information is measured by the target structure vibration sensor 40a, and the countermeasure force applied to the countermeasure device 20 is set based on the measured vibration information. In the second embodiment, the target structure vibration is set. A countermeasure force applied to the countermeasure device 20 is set using a displacement sensor 41 that is simpler than the sensor 40a.

  FIG. 9 shows a schematic configuration of the vibration damping device 50 according to the second embodiment. The vibration damping device 50 differs from the vibration damping device 10 of the first embodiment in that a vibration body 42 is installed on the installation surface A via a coil spring 43 and a displacement sensor 41 that measures the displacement of the vibration body 42 is used. Is in place. The controller 30 acquires displacement information measured by the displacement sensor 41.

  Here, as in the first embodiment, the frequency f1 of the main forced vibration component is known, and the natural frequency of the vibrating body 21 is set so that the phase is 180 ° behind the frequency. In addition, in the second embodiment, the natural frequency of the vibrating body 42 is set so that the phase is delayed by 180 ° with respect to the frequency of the main forced vibration component. Therefore, the vibration reduction effect can be increased by measuring the behavior of the vibrating body 42 with the displacement sensor 41 and driving the actuator 25 of the countermeasure device 20 based on the result.

Next, the operation procedure of the vibration damping device 50 will be described with reference to FIG.
For example, when vertical slack occurs in a concert, the displacement of the vibrating body 42 (vibrating body response) is measured by the displacement sensor 41 (S201). By this measurement, the forced vibration countermeasure controller 32 of the controller 30 specifies the amplitude of the vibrating body 42 as, for example, A1 (m). However, the forced vibration countermeasure controller 32 performs a simulation, which will be described later, using a countermeasure device model as shown in S207 of FIG. 10 as a premise for obtaining the amplitude A1.

The forced vibration countermeasure controller 32 obtains a disturbance by back calculation from the amplitude: A1 (m) (S203). In order to obtain the disturbance by back calculation, the table shown in FIG. 8 is referred to. In the case of amplitude: A1 (m), the disturbance amplitude is obtained as A1 / a1 (N). As described above, f1 is known.
Next, the forced vibration countermeasure controller 32 sets a countermeasure force for canceling the disturbance obtained by the reverse calculation (S205). This countermeasure force is set as the same amplitude as the disturbance amplitude. That is, the countermeasure force is set to amplitude: β * A1 / a1 (N). Note that β is an arbitrary coefficient.

Next, the simulation of S207 will be described.
The displacement information of the countermeasure device 20 obtained by the displacement sensor 41 includes the behavior (displacement) to which the countermeasure force is applied. At this time, the device response after amplification is further amplified at the next time, and the response diverges. Therefore, the target structure is vibrated by forced disturbance, the response of the countermeasure device 20 that is passively vibrated thereby is always grasped, and the countermeasure force is set based on the result.
From the displacement information of the countermeasure device 20 obtained by the displacement sensor 41, the forced vibration countermeasure controller 32 obtains a response (displacement) generated in the countermeasure device 20 only by the countermeasure force β * A1 / a1 (N) by simulation. By subtracting this result from the displacement of the vibrating body 42 (vibrating body response) measured by the displacement sensor 41, the amplitude A1 (m) due to the passive vibration of the countermeasure device 20 due to forced disturbance is specified. (S203). Based on this result, the next countermeasure force is set (S205).

<Third Embodiment>
In the vibration damping device 50 according to the second embodiment, the vibrating body 42 is installed on the installation surface A via the coil spring 43, the displacement of the vibrating body 42 due to the disturbance is measured, and the disturbance is calculated from the displacement by reverse calculation. Based on this, the countermeasure force applied to the countermeasure device 20 is set, but in the third embodiment, the displacement of the countermeasure device 20 is measured by the displacement sensor 44 and the countermeasure force applied to the countermeasure device 20 is set.

  Here, as in the first embodiment, the frequency of the main forced vibration component is known, and the natural frequency is set so that the phase of the countermeasure device 20 is 180 ° behind the frequency. The vibration reduction effect can be increased by measuring the behavior of the countermeasure device 20 with the displacement sensor 44 and driving the actuator 25 of the countermeasure device 20 based on the result. As the displacement sensor 44, a sensor provided in the countermeasure device 20 can be used.

Next, the operation procedure of the vibration damping device 60 will be described with reference to FIG.
For example, when vertical slack occurs in a concert, the displacement (vibrating body response) of the countermeasure device 20 is measured by the displacement sensor 44 (S301). By this measurement, the forced vibration countermeasure controller 32 of the controller 30 specifies the amplitude of the countermeasure device 20 as, for example, A1 (m). However, the forced vibration countermeasure controller 32 performs a simulation, which will be described later, using a countermeasure device model as shown in S307 of FIG. 12 as a premise for obtaining the amplitude A1.

The forced vibration countermeasure controller 32 obtains a disturbance by back calculation from the amplitude: A1 (m) (S303). In order to obtain the disturbance by back calculation, the table shown in FIG. 8 is referred to. In the case of amplitude: A1 (m), the disturbance amplitude is obtained as A1 / a1 (N). As described above, f1 is known.
Next, the forced vibration countermeasure controller 32 sets a countermeasure force for canceling the disturbance obtained by the reverse calculation (S305). This countermeasure force is set as the same amplitude as the disturbance amplitude. That is, the countermeasure force is set to amplitude: β * A1 / a1 (N). Note that β is an arbitrary coefficient.

Next, the simulation of S307 will be described.
The displacement of the countermeasure device 20 obtained by the displacement sensor 44 includes a behavior (displacement) to which a countermeasure force is applied. At this time, the device response after amplification is further amplified at the next time, and the response diverges. Therefore, the target structure is vibrated by forced disturbance, the response of the countermeasure device 20 that is passively vibrated thereby is always grasped, and the countermeasure force is set based on the result.
The forced vibration countermeasure controller 32 obtains a response (displacement) generated in the countermeasure device 20 only by the countermeasure force β * A1 / a1 (N) from the displacement information obtained by the displacement sensor by simulation. By subtracting this result from the displacement (vibrator response) of the countermeasure device 20 measured by the displacement sensor 44, the amplitude: A1 (m) due to the passive vibration of the countermeasure device 20 due to forced disturbance is specified. (S303). Based on this result, the next countermeasure force is set (S305).

As described above, in the first to second embodiments of the present invention, the natural frequency of the vibrating body 21 is set so that the vibration phase of the vibrating body 21 due to forced vibration is delayed by 180 °. There is no need to calculate the phase as a control force applied to the motor 21, and the behavior (displacement) of the vibrator 21 may be set only by the amplification factor. Therefore, the forced vibration countermeasure controller 32 can be simplified.
If the amplitude ratio (m / N) for each vibration frequency of the target structure is known in advance, the countermeasure force can be set with a simple sensor that omits the acceleration sensor as in the second and third embodiments. can do.

It is a figure for demonstrating the damping effect when the disturbance of a natural frequency is input into the structure. It is a figure for demonstrating the damping effect by patent document 1 when the disturbance of a forced frequency is input into the structure. It is a figure for demonstrating the damping effect by this invention when the disturbance of a forced frequency is input into the structure. It is a figure which shows the structure outline of the damping device which concerns on 1st Embodiment. It is a figure which shows the control outline | summary of the damping device which concerns on 1st Embodiment. It is a figure which shows an example of the result of having performed the FFT process on the vibration detected by the sensor. It is a flowchart which shows the process sequence of the controller which concerns on 1st Embodiment. It is a figure which shows an example of the table which describes the amplitude ratio for every vibration frequency of the object structure which a controller hold | maintains. It is a figure which shows the structure outline of the damping device which concerns on 2nd Embodiment. It is a flowchart which shows the process sequence of the controller which concerns on 2nd Embodiment. It is a figure which shows the structure outline of the damping device which concerns on 3rd Embodiment. It is a flowchart which shows the process sequence of the controller which concerns on 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Damping device, 20 ... Countermeasure apparatus, 21, 42 ... Vibrating body, 25 ... Actuator, 30 ... Controller, 31 ... FFT device, 32 ... Forced vibration countermeasure controller, 40a ... Target structure vibration sensor, 40b ... Countermeasure apparatus Vibration sensor, 41, 44 ... Displacement sensor

Claims (2)

An apparatus that is disposed in proximity to a target structure to which forced vibration is applied, and that suppresses vibration generated in the target structure,
A countermeasure device including a vibrating body that is allowed to be displaced in a predetermined direction and a driving unit that drives the vibrating body;
A controller for controlling the operation of the driving means so as to suppress the vibration of the target structure due to the forced vibration,
The vibrator is
The vibration damping device, wherein the natural frequency is set so that the phase of vibration of the vibrating body due to the forced vibration is delayed within a range of 180 ° ± 10 ° from the phase of the forced vibration. A sensor for detecting vibration or displacement of the target structure or the countermeasure device;
The controller is
The vibration control device according to claim 1, wherein the driving unit is controlled based on information on the vibration or the displacement.

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