Physical quantity measuring device

Abstract

To provide a physical quantity measuring device with which durability can be improved.SOLUTION: A physical quantity measuring device 1 comprises: a physical quantity detector 11 for detecting the acceleration of a bridge girder BG and constituted to be capable of outputting a measurement signal corresponding to the measured acceleration; a measurement control unit 121 for controlling the measurement of acceleration by the physical quantity detector 11; a storage device 13 for storing measurement data based on the measurement signal; and a filter processing unit for mitigating the impact by an impacting factor that affects the measurement of acceleration by the physical quantity detector 11. The filter processing unit includes a mechanical filter unit 18 for mechanically mitigating the impact due to the impacting factor, and a digital arithmetic processing unit 122 for mitigating the impact due to the impacting factor by arithmetic operation.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a physical quantity measuring device. [Background technology]

[0002] BACKGROUND ART Conventionally, monitoring devices for measuring the soundness of bridge piers and the like are known (for example, Patent Document 1, etc.). In Patent Document 1, the spectrum of the vibration frequency of a bridge pier is analyzed, and based on the analysis results, the frequency distribution of the vibration frequency with the largest amplitude within a predetermined frequency band is tallied.The predominant frequency of the bridge pier is then calculated based on the frequency distribution of the vibration frequencies.This makes it possible to reduce the effects of environmental noise, etc. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-183955 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, it is desirable for the monitoring device such as that disclosed in Patent Document 1 to monitor the safety of bridge piers and the like over a long period of time. Therefore, it has been an issue to reduce factors that affect the electronic components used in the device and to improve their durability.

[0005] An object of the present invention is to provide a physical quantity measuring device that can improve durability. [Means for solving the problem]

[0006] The physical quantity measuring device of the present invention comprises a physical quantity detector configured to measure a physical quantity of a measured object and output a measurement signal corresponding to the measured physical quantity, a measurement control unit that controls measurement of the physical quantity by the physical quantity detector, a memory device that stores measurement data based on the measurement signal, and a filter processing unit that reduces the influence of influencing factors that affect the measurement of the physical quantity by the physical quantity detector, wherein the filter processing unit has a mechanical filter unit that mechanically reduces the influence of the influencing factors, and a digital calculation processing unit that reduces the influence of the influencing factors by calculation.

[0007] In the present invention, the influence of an influencing factor that affects the measurement of a physical quantity by a physical quantity detector is reduced by a filter processing unit. The filter processing unit has a mechanical filter unit that mechanically reduces the influence of the influencing factor and a digital arithmetic processing unit that reduces the influence by calculation. This allows the process of reducing the influence of the influencing factor to be distributed between the mechanical filter unit and the digital arithmetic processing unit. Therefore, by reducing the calculation time by the digital arithmetic processing unit, electrical stress on the digital arithmetic processing unit can be reduced, thereby improving durability.

[0008] The physical quantity measuring device of the present invention preferably includes: a timer configured to be able to measure time and outputting a start signal and a stop signal based on a time table stored in the storage device; a control device having the measurement control unit and the digital calculation processing unit; a power supply unit that supplies power to the control device; and a power supply switching device that turns on the supply of power to the control device by the power supply unit based on the start signal output from the timer, and turns off the supply of power to the control device by the power supply unit based on the stop signal. In this configuration, a power supply switching device is provided that turns on / off the power supply to the control device based on the start signal and stop signal output from the timer, so that the control device can be started when the physical quantity detector measures a physical quantity and the power supply to the control device can be turned off at other times, thereby reducing the power consumption of the control device.

[0009] In the physical quantity measuring device of the present invention, it is preferable that the power supply unit has an external power supply unit that inputs power to be supplied to the control device from the outside, a battery unit that stores power to be supplied to the control device, and a power supply switching mechanism that switches between power supply by the external power supply unit and power supply by the battery unit. This configuration is equipped with a power supply switching mechanism that switches between power supply from the external power supply unit and power supply from the battery unit, so that when an external power source is available, it switches to power supply from the external power supply unit, and when an external power source is not available, it switches to power supply from the battery unit.

[0010] In the physical quantity measuring device of the present invention, it is preferable that a communication device is provided that transmits the measurement data stored in the storage device to an external device, and that the communication device has a wireless communication unit that transmits the measurement data to the external device via wireless communication, and a wired communication unit that transmits the measurement data to the external device via wired communication. This configuration has a wireless communication unit that transmits measurement data to an external device via wireless communication and a wired communication unit that transmits measurement data to an external device via wired communication, so that measurement data can be transmitted to an external device via either wireless or wired communication. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing a schematic configuration of a physical quantity monitoring system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a block diagram showing a schematic configuration of the physical quantity measuring device main body according to the embodiment. [Figure 3]FIG. 2 is a cross-sectional view showing an outline of the main body of the physical quantity measuring device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] [Embodiment] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the general configuration of a physical quantity monitoring system 100 of this embodiment. As shown in FIG. 1, a physical quantity monitoring system 100 according to this embodiment monitors the soundness of a pier BP of a bridge B spanning a river R. The piers BP support the bridge girders BG, on which roads and railway tracks are installed for people and vehicles to pass.

[0013] The physical quantity monitoring system 100 includes a physical quantity measuring device 1 installed at a bridge pier BP, and a data monitoring device 200. The physical quantity measuring device 1 comprises a physical quantity measuring device main body 10 and a solar panel 120. The physical quantity measuring device main body 10 is installed at an arbitrary position on the upper part of the bridge pier BP (object to be measured) in order to measure the microtremors of the bridge pier BP. The solar panel 120 receives sunlight and converts the energy of the received sunlight into electricity. The solar panel 120 only needs to be installed in a position where it can receive sunlight, and is installed, for example, on a street light pole LP on the bridge girder BG. The data monitoring device 200 is configured as a portable device (for example, a smartphone or tablet terminal) that can be carried by a bridge inspector, for example. The data monitoring device 200 is an example of an external device of the present invention.

[0014] [Physical quantity measuring device body 10] FIG. 2 is a block diagram showing a schematic configuration of the physical quantity measuring device main body 10. As shown in FIG. 2, the physical quantity measuring device main body 10 includes a physical quantity detector 11, a control device 12, a storage device 13, a communication device 14, a power supply unit 15, a timer 16, a power supply switching device 17, and a mechanical filter unit 18. In this embodiment, these are housed in a single case to form a unit. In other words, the physical quantity measuring device main body 10 is a smart sensor in which each function is integrated.

[0015] The physical quantity detector 11 is configured as an acceleration sensor that outputs measured vibrations corresponding to the acceleration (vibration information) of microtremors in a direction perpendicular to the axial direction of the bridge girder BG (direction perpendicular to the bridge axis). Microtremors are minute vibrations that constantly occur in the bridge pier BP due to the influence of, for example, wind or water currents. A highly accurate three-axis accelerometer capable of detecting minute vibrations, such as a MEMS accelerometer, is used as the acceleration sensor constituting the physical quantity detector 11. By using a MEMS accelerometer, it can be driven inexpensively and with low power consumption.

[0016] The control device 12 is configured with a CPU (Central Processing Unit), a memory, etc., and executes processing by the CPU executing a program stored in the memory. The control device 12 includes a measurement control section 121 , a digital calculation processing section 122 , and a communication control section 123 . The measurement control unit 121 is configured to control the measurement of acceleration by the physical quantity detector 11 . The digital arithmetic processing unit 122 is configured to execute a process for reducing, by calculation, the influence of an influencing factor that affects the measurement of the physical quantity (acceleration) by the physical quantity detector 11. Details of the calculation process by the digital arithmetic processing unit 122 will be described later. The communication control unit 123 is configured to control data communication by the communication device 14. Specifically, the communication control unit 123 controls the communication device 14 so that the measurement data stored in the storage device 13 is communicated to the data monitoring device 200.

[0017] The storage device 13 is composed of a non-volatile memory such as a RAM (Random Access Memory) or an SD card, and is configured to store measurement data based on the measurement signal output by the physical quantity detector 11 and a time table, which will be described later.

[0018] The communication device 14 is configured to transmit the measurement data stored in the storage device 13 to the data monitoring device 200. In this embodiment, the communication device 14 has a wireless communication unit 141 that transmits the measurement data to the data monitoring device 200 by wireless communication (e.g., Bluetooth (registered trademark), Wi-Fi (registered trademark), etc.), and a wired communication unit 142 that transmits the measurement data to the data monitoring device 200 by wired communication (e.g., Ethernet (registered trademark), USB, etc.). As described above, in this embodiment, the communication device 14 has the wireless communication unit 141 and the wired communication unit 142, and therefore, measurement data can be transmitted to the data monitoring device 200 regardless of whether it is wireless or wired communication. Furthermore, even if one of the wireless communication unit 141 and the wired communication unit 142 fails, the other of the wireless communication unit 141 and the wired communication unit 142 that is not failed can be used to transmit the measurement data to the data monitoring device 200. This makes it possible to improve the durability of the physical quantity measuring device 1.

[0019] The power supply unit 15 is configured to supply power to the physical quantity detector 11, the control device 12, the communication device 14, etc. In this embodiment, the power supply unit 15 has an external power supply unit 151, a battery unit 152, and a power supply switching mechanism 153. The external power supply unit 151 is configured to receive power from an external power source. The battery unit 152 is configured to be able to store power to be supplied to the control device 12 etc. In this embodiment, the battery unit 152 is configured as a secondary battery that can store power generated by the solar panel 120.

[0020] The power supply switching mechanism 153 is configured to be able to switch between power supply by the external power supply unit 151 and power supply by the battery unit 152. For example, when the external power supply unit 151 is connected to an external power source, the power supply switching mechanism 153 switches to power supply by the external power supply unit 151. Furthermore, when the external power supply unit 151 is not connected to an external power source and the battery unit 152 is sufficiently charged, the power supply switching mechanism 153 switches to power supply by the battery unit 152. Note that an electronic switch (diode switch) that gives priority to the power source with the greater supply capacity can be used as the power supply switching mechanism 153.

[0021] As described above, in this embodiment, the power supply switching mechanism 153 is provided to switch between power supply by the external power supply unit 151 and power supply by the battery unit 152, so that when an external power source is available, the power supply can be switched to that by the external power supply unit 151, and when an external power source is not available, the power supply can be switched to that by the battery unit 152. Between the power supply switching mechanism 153 and each of the power sources of the external power supply unit 151 and the battery unit 152, a DC-DC converter (not shown) or the like is connected to stabilize the DC voltage.

[0022] Timer 16 is configured to be able to measure time, and is configured to output a start signal and a stop signal based on a time table stored in storage device 13. For example, if storage device 13 stores the time on the hour (e.g., 13:00, 14:00, etc.) as the time to output a start signal and the time five minutes after the hour (e.g., 13:05, 14:05, etc.) as the time to output a stop signal, timer 16 outputs a start signal on the hour and outputs a stop signal five minutes after the hour.

[0023] The power supply switching device 17 is configured to turn on the supply of power from the power supply unit 15 to the control device 12, the physical quantity detector 11, etc., based on the start signal output from the timer 16, and to turn off the supply of power from the power supply unit 15 to the control device 12, the physical quantity detector 11, etc., based on the stop signal. That is, the power supply switching device 17 is configured to turn on / off the supply of power to the control device 12, etc., based on the start signal / stop signal output from the timer 16. This allows the control device 12, etc. to be started when the physical quantity detector 11 is measuring a physical quantity, and the power supply to the control device 12, etc. to be turned off at other times, thereby reducing the power consumption of the control device 12, etc.

[0024] FIG. 3 is a cross-sectional view showing an outline of the physical quantity measuring device main body 10. As shown in FIG. 3, the mechanical filter unit 18 is disposed above the battery unit 152. In this embodiment, a circuit board 19 is disposed above the mechanical filter unit 18, and the physical quantity detector 11 and the control device 12 are disposed on the circuit board 19. That is, in this embodiment, the mechanical filter unit 18 is disposed so as to support the physical quantity detector 11 and the control device 12 via the circuit board 19.

[0025] In this embodiment, the mechanical filter unit 18 is configured to include a damping material such as a spring or vibration-proof gel, and is configured to reduce the influence of influencing factors that affect the measurement of the physical quantity by the physical quantity detector 11. The mechanism by which the mechanical filter unit 18 reduces the influencing factors will be described in detail later.

[0026] [Mechanisms for reducing impact factors] Next, the mechanism for reducing the influencing factors will be described. As described above, in this embodiment, the physical quantity detector 11 is configured as an acceleration sensor that measures the acceleration of microtremors in a direction perpendicular to the axial direction of the bridge girder BG. Microtremors are small vibrations that constantly occur in the bridge piers BP due to the influence of, for example, wind or water currents. Therefore, if a vehicle such as an automobile or train passes on the road or railroad track attached to the bridge girder BG while the physical quantity detector 11 is measuring the acceleration of the microtremors, the vibration of the bridge girder BG caused by the passage of the vehicle becomes noise in the measurement of the acceleration of the microtremors. In other words, the vibration of the bridge girder BG caused by the passage of the vehicle becomes an influencing factor that affects the acceleration measurement. As described above, in this embodiment, the physical quantity detector 11 that measures acceleration is supported by the mechanical filter unit 18 that has a damping material such as a spring or vibration-proof gel, and therefore the mechanical filter unit 18 damps vibrations caused by the passing of a vehicle, thereby reducing transmission of the vibrations to the physical quantity detector 11. Therefore, the mechanical filter unit 18 can reduce the influence of influencing factors that affect the measurement of acceleration by the physical quantity detector 11.

[0027] Furthermore, in this embodiment, the digital arithmetic processing unit 122 is configured to reduce, through arithmetic processing, the influence of vibrations caused by the passing of vehicles in the measurement of acceleration due to microtremors by the physical quantity detector 11. For example, the digital arithmetic processing unit 122 performs arithmetic processing to separate the acceleration component due to microtremors from the acceleration component due to the passing of vehicles in the acceleration measurement data by the physical quantity detector 11. Then, the digital arithmetic processing unit 122 reduces the influence of influencing factors that affect the acceleration measurement by subtracting the acceleration component due to the passing of vehicles from the entire measurement data.

[0028] In this embodiment, the measurement data input to the digital arithmetic processing unit 122 is the measurement data after the influence of influencing factors has been reduced by the mechanical filter unit 18, and therefore it is possible to reduce the amount of arithmetic processing by the digital arithmetic processing unit 122. That is, in this embodiment, the processing for reducing the influence of influencing factors is distributed between the mechanical filter unit 18 and the digital arithmetic processing unit 122, and therefore the arithmetic processing time by the digital arithmetic processing unit 122 can be reduced and electrical stress on the digital arithmetic processing unit 122 can be reduced, thereby improving durability. The mechanical filter unit 18 and the digital arithmetic processing unit 122 constitute a filter processing unit of the present invention.

[0029] [Effects of this embodiment] The present embodiment as described above can achieve the following effects. (1) In this embodiment, the filter processing unit is configured to reduce the influence of influencing factors that affect the measurement of the physical quantity (acceleration) by the physical quantity detector 11. The filter processing unit has a mechanical filter unit 18 that mechanically reduces the influence of the influencing factors and a digital arithmetic processing unit 122 that reduces the influence by calculation. This allows the process of reducing the influence of the influencing factors to be distributed between the mechanical filter unit 18 and the digital arithmetic processing unit 122. Therefore, by reducing the calculation time by the digital arithmetic processing unit 122, it is possible to reduce electrical stress on the digital arithmetic processing unit 122, thereby improving durability.

[0030] (2) In this embodiment, the power supply switching device 17 is provided, which turns on / off the power supply to the control device 12, etc., based on the start signal and stop signal output from the timer 16. Therefore, the control device 12, etc. can be started when the physical quantity detector 11 measures the physical quantity (acceleration), and the power supply to the control device 12, etc. can be turned off at other times. This makes it possible to reduce the power consumption of the control device 12, etc.

[0031] (3) In this embodiment, a power supply switching mechanism 153 is provided that switches between power supply by the external power supply unit 151 and power supply by the battery unit 152. Therefore, when an external power source is available, the power supply can be switched to that by the external power supply unit 151, and when an external power source is not available, the power supply can be switched to that by the battery unit 152.

[0032] (4) In this embodiment, the device has a wireless communication unit 141 that transmits measurement data to the data monitoring device 200 via wireless communication and a wired communication unit 142 that transmits measurement data to the data monitoring device 200 via wired communication, so that measurement data can be transmitted to the data monitoring device 200 regardless of whether it is via wireless or wired communication.

[0033] [Variations] The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention. In the above embodiment, the physical quantity measuring device 1 is configured to be able to measure the acceleration of microtremors of the pier BP of the bridge B spanning the river R, but is not limited to this. For example, it may be configured to be able to measure the amplitude of a road provided on the bridge girder BG, and it is only necessary that it is configured to be able to measure the physical quantity of interest.

[0034] In the above embodiment, the data monitoring device 200 is configured as a portable device such as a smartphone or tablet terminal, but is not limited to this and may be configured as, for example, a stationary device.

[0035] In the above embodiment, the battery unit 152 is configured to be charged with power generated by the solar panel 120, but this is not limiting. For example, the battery unit may be configured to be rechargeable by an external power source. In this case, the solar panel 120 may not be provided.

[0036] In the above embodiment, the timer 16 is configured to output a start signal and a stop signal based on the time table stored in the storage device 13, but this is not limiting. For example, the timer may be configured to output a start signal and a stop signal at predetermined intervals. Furthermore, the time table stored in the storage device 13 and the measurement conditions of the physical quantity detector 11 may be configured to be changeable through the data monitoring device 200. [Explanation of symbols]

[0037] 1...physical quantity measuring device, 10...physical quantity measuring device main body, 11...physical quantity detector, 12...control device, 13...memory device, 14...communication device, 15...power supply unit, 16...timer, 17...power supply switching device, 18...mechanical filter unit (filter processing unit), 19...circuit board, 100...physical quantity monitoring system, 120...solar panel, 121...measurement control unit, 122...digital calculation processing unit (filter processing unit), 123...communication control unit, 141...wireless communication unit, 142...wired communication unit, 151...external power supply unit, 152...battery unit, 153...power supply switching mechanism, 200...data monitoring device (external device), B...bridge, BG...bridge girder (measured object), BP...bridge pier, LP...street light pole, R...river.

Claims

1. a physical quantity detector configured to measure a physical quantity of a measurement object and output a measurement signal corresponding to the measured physical quantity; a measurement control unit that controls measurement of the physical quantity by the physical quantity detector; a storage device that stores measurement data based on the measurement signal; a filter processing unit that reduces the influence of an influencing factor that affects the measurement of the physical quantity by the physical quantity detector, The filter processing unit includes a mechanical filter unit that mechanically reduces the influence of the influencing factor, and a digital calculation processing unit that reduces the influence of the influencing factor by calculation. A physical quantity measuring device characterized by:

2. 2. The physical quantity measuring device according to claim 1, a timer configured to be able to measure time and outputting a start signal and a stop signal based on a time table stored in the storage device; a control device having the measurement control unit and the digital calculation processing unit; a power supply unit that supplies power to the control device; a power supply switching device that turns on the supply of power to the control device by the power supply unit based on the start signal output from the timer, and turns off the supply of power to the control device by the power supply unit based on the stop signal. A physical quantity measuring device characterized by:

3. 3. The physical quantity measuring device according to claim 2, The power supply unit includes an external power supply unit that inputs power to be supplied to the control device from an external source, a battery unit that stores the power to be supplied to the control device, and a power supply switching mechanism that switches between power supply by the external power supply unit and power supply by the battery unit. A physical quantity measuring device characterized by:

4. 2. The physical quantity measuring device according to claim 1, a communication device that transmits the measurement data stored in the storage device to an external device; The communication device includes a wireless communication unit that transmits the measurement data to the external device by wireless communication, and a wired communication unit that transmits the measurement data to the external device by wired communication. A physical quantity measuring device characterized by:

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