Vibration control systems, vibration control methods

Abstract

We provide a vibration damping system that can also dampen the initial vibrations that are transmitted. [Solution] The vibration damping system 1, which dampens vibrations of a structure caused by transmission from a vibration source through the ground, includes a vibration sensor 10 installed between the vibration source 100 and the structure 110, a vibration damping device 30 that excites the structure 110, and a control device 20 that controls the excitation of the vibration damping device 30. The control device 20 stores the vibration transfer function from the point where the vibration sensor 10 is installed to the structure 110, estimates the vibration occurring in the structure 110 based on the vibration measured by the vibration sensor 10 and the transfer function, calculates an excitation force that cancels out the estimated vibration, and controls the drive of the vibration damping device 20 based on the calculated excitation force.

Description

Technical Field

[0001] The present invention relates to a vibration control system and a vibration control method.

Background Art

[0002] In factories and the like, vibrations and impacts are generated by the driving of processing equipment. Also, on roads and the like, vibrations and impacts are generated by the running of large vehicles. Such impacts and vibrations are transmitted through the building structure and cause discomfort to the building users.

[0003] In contrast, for example, in Patent Document 1, an active vibration control device that generates a vibration control force is installed at a location where vibration damage to a structure occurs, and drive control of the active vibration control device is performed based on vibration information measured by a vibration sensor installed at the same location.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the invention described in Patent Document 1, since vibration control is performed after receiving vibration, it is not possible to control the initial impact-like vibration that is transmitted.

[0006] The present invention has been made in view of the above problems, and an object thereof is to provide a vibration control system capable of controlling even the initially transmitted vibration.

Means for Solving the Problems

[0007] According to one aspect of the present invention, a vibration damping system is provided for damping vibrations of a structure that are transmitted from a vibration source through the ground, and includes a vibration sensor installed between the vibration source and the structure, a vibration damping device that excites the structure, and a control device that controls the excitation of the vibration damping device, wherein the control device stores a vibration transfer function from the point where the vibration sensor is installed to the structure, estimates the vibration occurring in the structure based on the vibration measured by the vibration sensor and the transfer function, calculates an excitation force that cancels out the estimated vibration, and controls the driving of the vibration damping device based on the calculated excitation force.

[0008] According to the above embodiment, since the vibration sensor is installed between the vibration source and the structure, it is possible to calculate the vibration occurring in the structure based on the vibration measured by the vibration sensor and the transfer function before the vibration is transmitted to the structure, thus enabling the initial vibration to be suppressed.

[0009] Furthermore, according to one aspect of the present invention, the transfer function is calculated based on the vibrations measured by the second vibration sensor and the vibrations received by the vibration sensor, when vibrations are applied to or near the vibration source, and the vibrations are measured by a vibration sensor and a second vibration sensor installed on the structure.

[0010] According to the above embodiment, the vibrations in the vibration sensor generated by actually applying vibrations and the vibrations generated in the structure are measured, and the transfer function is determined based on these measurements, so an accurate transfer function can be calculated.

[0011] Furthermore, according to one aspect of the present invention, the transfer function is calculated based on an approximate spectrum obtained by dividing the vibration spectrum measured by the second vibration sensor by the vibration spectrum measured by the vibration sensor to obtain the transfer function spectrum.

[0012] According to the above embodiment, since an approximate spectrum is used, the calculation is simpler compared to using the transfer function directly. This increases the calculation speed and allows for simultaneous control of vibration propagation.

[0013] Furthermore, according to one aspect of the present invention, the approximate spectrum is a function having peaks that coincide with at least some of the peaks of the transfer function spectrum.

[0014] According to the above embodiment, since the approximate spectrum matches at least a portion of the peaks of the transfer function spectrum, oscillations at more easily transmitted frequencies can be reliably suppressed.

[0015] Furthermore, according to one aspect of the present invention, a vibration damping method is provided for damping vibrations of a structure transmitted from a vibration source through the ground, comprising a vibration sensor provided between a vibration source and a structure, a vibration damping device for exciting the structure, and a control device for controlling the excitation of the vibration damping device, wherein the control device stores a vibration transfer function from the vibration sensor to the vibration damping device, and the method includes the steps of: estimating the vibration occurring in the structure based on the vibration measured by the vibration sensor and the transfer function; calculating an excitation force that cancels out the estimated vibration; and controlling the drive of the vibration damping device based on the calculated excitation force. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a vibration damping system that can dampen even the initial vibrations that are transmitted. [Brief explanation of the drawing]

[0017] [Figure 1] This is a diagram showing the configuration of the vibration damping system according to this embodiment. [Figure 2] This is a diagram illustrating the method for calculating the transfer function. [Figure 3] This graph shows an example of the calculated frequency domain transfer function spectrum T(f). [Figure 4] This diagram illustrates a method for damping vibrations in a structure using the vibration system of this embodiment. [Modes for carrying out the invention]

[0018] Hereinafter, the vibration control system and method of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing the configuration of the vibration control system according to the present embodiment. The vibration control system 1 of the present embodiment is for controlling the sway of the structure 110 caused by the vibration generated by the vibration source 100. As shown in FIG. 1, it includes a vibration sensor 10 for detecting vibration, a control device 20, and a vibration control device 30. The vibration sensor 10 and the control device 20 are communicably connected wirelessly or by wire, and the control device 20 and the vibration control device 30 are communicably connected wirelessly or by wire.

[0019] Examples of the vibration source 100 include machines such as press machines in factories, trunk roads where large vehicles pass, and facilities where vibration occurs such as concert venues. The vibration generated from the vibration source 100 is transmitted through the ground to the structure 110.

[0020] The vibration sensor 10 is a sensor that detects the vibration generated in the attached object, and is provided between the vibration source 100 and the structure 110. Here, the space between the vibration source 100 and the structure 110 does not mean only on the straight line connecting the vibration source 100 and the structure 110, but also includes the vicinity of the straight line connecting the vibration source 100 and the structure 110. Also, the vibration sensor 10 is preferably provided near the vibration source 100. A plurality of vibration sensors 10 may be provided on the vibration propagation path, and the transfer function may be obtained for each of the plurality of sensors 10. The vibration reaching based on the plurality of sensors is respectively estimated, and the estimated vibration waveforms are processed to estimate the reaching waveform. As a result, since there are a plurality of estimation models, the estimation accuracy is improved. Also, even if some of the plurality of vibration sensors are damaged, prediction is possible.

[0021] The control device 20 is composed of, for example, a computer and can control the drive of the vibration control device 30. The transfer function of the vibration from the vibration sensor 10 to the structure 110 is stored in the control device 20 in advance. Then, based on the vibration received by the vibration sensor 10, the vibration generated in the structure 11 is estimated, and the drive of the vibration control device 30 is controlled to cancel the estimated vibration for vibration control.

[0022] The vibration damping device 30 is, for example, an active mass damper, which is a device capable of moving a heavy mass in the horizontal and vertical directions. The vibration damping device 30 generates a reverse force against the vibration generated in the structure 110 under the control of the control device 20, thereby damping the vibration of the structure. The vibration damping device 30 is preferably provided, for example, on the roof of the structure 110 or in the space between the upper and lower floors.

[0023] Next, a method for calculating the transfer function stored in the control device will be described. FIG. 2 is a diagram for explaining a method for calculating the transfer function. First, a second vibration sensor 40 is installed on the structure 110. The location where the second vibration sensor 40 is installed is preferably near the vibration damping device 30. Next, vibration is applied to the vibration source 100 or its vicinity. As the applied vibration, the vibration of the vibration source 100 may be used, or a white noise or sweep signal may be generated by a shaker. However, the generated vibration needs to be a signal that covers the frequency of the vibration generated by the vibration source 100. The generated vibration propagates to the structure 110 through the ground. Then, the propagated vibration is detected by the vibration sensor 10 of the vibration damping system 1 and the second vibration sensor 40 installed on the structure. Note that the location where the vibration is applied is preferably the vibration source 100 (excitation source) or its vicinity. For example, the machine that is the vibration source 100 may be directly excited, the foundation of the machine that is the vibration source 100 may be excited, the slab around the vibration source 100 may be excited, the ground near the vibration source 100 may be excited, or the ground between the vibration source 100 and the second vibration sensor 40 may be excited.

[0024] Next, the vibration W1(t) obtained from the vibration sensor 10 of the vibration damping system 1 is subjected to Fourier transform (FFT) to calculate the frequency spectrum F1(f). Also, the vibration W2(t) obtained from the second vibration sensor 40 installed on the structure 110 is subjected to Fourier transform (FFT) to calculate the frequency spectrum F2(f). Then, the transfer function spectrum T(f) in the frequency domain is calculated by dividing F2(f) by F1(f) in the frequency domain.

[0025] Figure 3 is a graph showing an example of a calculated frequency domain transfer function spectrum T(f). As shown in the figure, the transfer function spectrum has multiple peaks due to the influence of the resonant frequency of the structure. In response to this, as shown by the dashed line in Figure 3, from among the multiple peaks of the transfer function spectrum, a peak that reveals the vibration characteristics of the structure (floor, column, etc.) is selected based on the characteristics of the ground and the natural frequencies of the structure, and an approximate spectrum is calculated such that the peak matches the selected peak. In other words, an approximate transfer function spectrum T'(f) is obtained in which the vibration modes (frequencies) of at least some of the multiple peaks match the vibration modes (frequencies) of the peak. The approximate transfer function spectrum T'(f) is calculated considering the height and width (angle of the curve) of the peaks in the transfer function spectrum. For example, the approximate transfer function spectrum T'(f) can be approximated using a spline curve. Then, the approximate transfer function can be obtained by performing an inverse Fourier transform (IFFT) on the obtained approximate transfer function spectrum T'(f) (approximate spectrum). The approximate transfer function obtained in this way is stored as the transfer function in the control device.

[0026] According to the vibration control system 1 of this embodiment, vibration control of a structure can be performed as follows. Figure 4 is a diagram illustrating a method for damping vibrations in a structure using the vibration system of this embodiment. When vibrations are generated by the vibration source 100, the vibration sensor 10 detects the vibrations (measured vibrations). The vibrations detected by the vibration sensor 10 are transmitted to the control device 20. The signal transmitted from the vibration sensor 10 reaches the control device 20 faster than the vibrations themselves. The control device 20 multiplies the received vibrations by a transfer function in real time (convolution integral) to estimate the vibrations occurring in the structure (estimated vibrations). Next, the control device 20 calculates an excitation force (control vibration) that cancels out the estimated vibrations. In other words, the control device 20 calculates an excitation force that applies vibrations in opposite phase to the estimated vibrations. Then, it drives the damping device according to the calculated excitation force. As a result, the excitation force from the damping device 30 acts to cancel out the vibrations transmitted from the vibration source 100, thereby damping the vibrations of the structure 110.

[0027] According to this embodiment, the following effects are achieved. According to this embodiment, since the vibration sensor 10 is installed between the vibration source 100 and the structure 110, it is possible to calculate the vibration that will occur in the structure 110 based on the vibration measured by the vibration sensor 10 and the transfer function before the vibration is transmitted to the structure 110, so that the initial vibration can also be damped.

[0028] Furthermore, according to this embodiment, the transfer function is calculated by applying vibration to the vibration source 100 or its vicinity, measuring the vibration with a vibration sensor and a second vibration sensor 40 installed on the structure 110, and basing the calculation on the vibration measured by the second vibration sensor 40 and the vibration received by the vibration sensor 10. In this way, since the vibration at the vibration sensor 10 generated by actually applying vibration and the vibration generated in the structure 110 are measured and the transfer function is determined based on these measurements, an accurate transfer function can be calculated.

[0029] Furthermore, according to this embodiment, the transfer function is calculated based on an approximate spectrum obtained by dividing the vibration spectrum measured by the second vibration sensor 40 by the vibration spectrum measured by the vibration sensor 10 to obtain the transfer function spectrum. Because an approximate spectrum is used in this way, the calculation is simpler compared to using the transfer function directly. This increases the calculation speed and allows control to be performed simultaneously with the propagation of vibration.

[0030] Furthermore, according to this embodiment, the approximate spectrum is a function having peaks that coincide with at least some of the peaks of the transfer function spectrum. As a result, since the approximate spectrum coincides with at least some of the peaks of the transfer function spectrum, vibrations at frequencies that are more easily transmitted can be reliably suppressed. [Explanation of symbols]

[0031] 1: Vibration control system 10: Vibration sensor 11: Structure 20: Control device 30: Vibration damping device 40: Second vibration sensor 100: Vibration source 110: Structure F1: Frequency spectrum F2: Frequency spectrum T: Transfer function spectrum T': Approximate transfer function spectrum W1: Vibration W2: Vibration

Claims

1. A vibration control system that suppresses vibrations of a structure caused by transmission from a vibration source through the ground, A vibration sensor is provided between the vibration source and the structure, A vibration damping device for exciting the aforementioned structure, The control device includes a control device that controls the excitation of the vibration damping device, The control device stores the vibration transfer function from the point where the vibration sensor is installed to the structure. Based on the vibration measured by the vibration sensor and the transfer function, the vibration occurring in the structure is estimated. We calculate an excitation force that cancels out the estimated vibrations, The drive of the vibration damping device is controlled based on the calculated excitation force. Vibration damping system.

2. The aforementioned transfer function is, Vibration is applied to the vibration source or its vicinity, and the vibration is measured by the vibration sensor and a second vibration sensor provided on the structure. This is calculated based on the vibration measured by the second vibration sensor and the vibration received by the vibration sensor. The vibration damping system according to claim 1.

3. The aforementioned transfer function is, The transfer function spectrum is obtained by dividing the vibration spectrum measured by the second vibration sensor by the vibration spectrum measured by the first vibration sensor. This was calculated based on an approximate spectrum obtained by approximating the aforementioned transfer function spectrum. The vibration damping system according to claim 2.

4. The approximate spectrum is a function having peaks that coincide with at least some of the peaks of the transfer function spectrum. The vibration damping system according to claim 3.

5. A vibration control method for controlling vibrations of a structure transmitted from a vibration source through the ground, comprising: a vibration sensor provided between the vibration source and the structure; a vibration damping device for exciting the structure; and a control device for controlling the excitation of the vibration damping device, wherein the vibrations of the structure are controlled by a vibration sensor provided between the vibration source and the structure, The control device stores the vibration transfer function from the vibration sensor to the vibration damping device. The steps include: estimating the vibration occurring in the structure based on the vibration measured by the vibration sensor and the transfer function; The steps include: calculating an excitation force that cancels out the estimated vibrations; The step includes controlling the drive of the vibration damping device based on the calculated excitation force, Vibration damping methods.

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