JP6762577B2 - Displacement measurement system - Google Patents

Description

The present invention relates to a displacement measurement system, and more particularly to a displacement measurement system that measures the displacement state of a bridge flexure or strain.

Deflection measurement of bridges has been carried out for over 100 years. The measured value of the deflection measurement of the bridge changes depending on the speed of the train passing through the bridge, the number of passengers, the condition of the bridge girder, and the like.

As a technique for measuring the displacement of a bridge, a method of arranging a plurality of targets at predetermined positions on the bridge and imaging and measuring the targets with a CCD camera provided on an existing abutment or at a fixed point on land (Patent Document 1). )It has been known.

In addition, in bridge erection construction management, the target and the CCD camera with zoom are placed at positions separated from each other on the bridge, and the image data of the target captured by the CCD camera with zoom is image-processed by the image processor to bend the bridge. An apparatus and method for measuring the displacement of a component and a twisted component (Patent Document 2) are known.

In the measurement using the image data captured by the CCD camera, the deflection is measured with high accuracy by using the sampling moiré method.

Japanese Unexamined Patent Publication No. 8-210852 Japanese Unexamined Patent Publication No. 2008-57243

FIG. 20 shows an example of a system for measuring the displacement of a bridge using image data captured by a CCD camera.

A grid target 102 is attached to the bridge 101, and the target 102 is imaged by cameras 110A to 110D arranged at a fixed point outside the bridge 101. The local control units 120A are wiredly connected to the cameras 110A and 110B by cables, and the local control units 120B and 120C are wiredly connected to the 110C and 110D by cables, respectively. The local control units 120A to 120C are commanded by the command control unit 140 via the command units 130A, 130B, and 130C. The local control units 120A to 120C measure the displacement of the image data captured by the cameras 110A to 110D by using, for example, the sampling moire method.

Deflection measurement by the sampling moiré method has the problem of being vulnerable to camera vibration. Since the camera vibrates in a strong wind environment, the captured image data contains noise components due to the vibration. In the sampling moiré method, since the deflection and distortion are measured based on the deviation between the captured images, the noise component of the captured image data causes a decrease in measurement accuracy.

In an example of measuring the deflection of a bridge by the sampling moire method, the grid attached to the bridge is continuously photographed with a camera, and the displacement is measured based on the grid of the captured image obtained by each imaging and the grid of the reference captured image. To do. At the time of this measurement, the noise component included in the image data of the captured image becomes a measurement error, so it is desirable that the noise component be as small as possible.

The vibration of the camera itself becomes a factor of the noise component of the image data. For example, the vibration of the camera due to the wind displaces the camera, and this displacement becomes the image data noise component of the captured image. When a vehicle passes over the bridge, the lattice attached to the bridge is displaced by the passage of the vehicle in a windless state, but in the presence of wind, it is displaced by the wind in addition to being displaced by the passage of the vehicle, and this displacement is an image. It becomes a data noise component.

The vibration of the camera due to the wind is generated by the wind hitting the camera body, the wind hitting the tripod, and the wind hitting the cable connecting the camera body and the control PC.

The inventor of the present application has found that the wind hitting the cable is a major cause of camera vibration. When the cable connecting the camera and the control PC is blown by a strong wind, the cable pulls or shakes the camera, causing the camera to vibrate.

As a measure to improve the vibration caused by the wind, it is conceivable to install a plate that blocks the wind around the camera, but it takes time and cost to install it.
Further, as shown in FIG. 20, when a command signal is commanded from one command control unit to a plurality of image pickup devices installed at remote locations, the delay time differs between the plurality of image pickup devices. There's a problem. FIG. 21 shows that there is a difference in delay time among a plurality of imaging devices.

An object of the present invention is to solve the above-mentioned conventional problems and suppress blurring of the captured image caused by vibration of the camera due to wind and noise components of the image data of the captured image, and to improve the measurement accuracy of displacement measurement. The purpose is to plan.

The displacement measurement system of the present invention is composed of a slave unit and a master unit that perform wireless communication with each other. Wireless communication between the master unit and the slave unit is performed by protocol communication based on TCP. For this mutual communication, Wi-Fi communication (wireless LAN communication) or Bluetooth (short-distance data communication of a digital device) can be used. In Wi-Fi communication, the frequency band is 2.4 GHz or 920 MHz. The frequency used can be switched according to the environment around the measurement site. It should be noted that communication can be performed in the 920 MHz band, but at 920 MHz, the displacement data which is the calculation result can be compressed and transmitted / received.

The slave unit captures an image target (target) based on the command signal of the master unit and acquires image data. The slave unit or the master unit analyzes the acquired image data and measures the displacement of the imaging target. The displacement measurement system of the present invention can transmit the data acquired by the slave unit to the master unit without using a cable by communicating wirelessly between the slave unit and the master unit. In a configuration in which the base unit is connected by a cable, it is possible to suppress blurring of the captured image caused by shaking of the cable and noise components of the image data of the captured image.

The displacement measurement system of the present invention includes a slave unit and a master unit that perform mutual communication, and the first embodiment is not limited to a single slave unit or a plurality of slave units, and a plurality of slave units. It has a second form of. In the form of wireless communication between the slave unit and the master unit, the relationship between the slave unit and the master unit corresponds to the relationship between the imaging client and the measurement server.

[First form of displacement measurement system]
The first form of the displacement measurement system of the present invention is a form in which the number of slave units is not limited to a single unit or a plurality of slave units, and the slave unit and the master unit perform wireless communication with each other.

(Cordless handset)
The slave unit includes an image pickup device and a transmitter / receiver on the slave unit side. The image pickup device included in the slave unit acquires the image data of the image pickup target provided on the measurement target based on the command signal of the master unit. The slave unit-side transmitter / receiver included in the slave unit receives a command signal from the master unit and transmits image data and / or analysis data derived from the image data to the master unit.

(Master unit)
The master unit includes a transmitter / receiver on the master unit side. The master unit-side transmitter / receiver provided in the master unit transmits a command signal to the slave unit, and receives image data and / or analysis data from the slave unit. The master unit can be mounted on a moving body such as a vehicle equipped with an operating battery, and wirelessly transmits a command signal and image data in the vicinity of a slave unit fixedly arranged near a measurement target such as a bridge. And / or receive analysis data.

By installing the power supply in the vehicle, the work of transporting and installing a heavy generator near the camera becomes unnecessary, and the burden on the operator is reduced. In addition, when the generator is installed on a slope, there is a risk of slipping and falling, which may lead to occupational accidents, but this problem can be solved by installing a power supply inside the vehicle. ..

Furthermore, when the worker works inside the vehicle, it becomes a measure against heat stroke, a measure against cold weather, and a measure against snowfall and rain (drip-proof property), and the convenience of work is improved.

(Slave unit or master unit)
The slave unit or the master unit includes an analysis unit that analyzes image data. The analysis unit includes a displacement analysis unit, which analyzes the displacement of the imaged object from the image data and obtains analysis data. The analysis data obtained by the displacement data analysis of the displacement analysis unit is the displacement data.

[Second form of displacement measurement system]
The second form of the displacement measurement system of the present invention is a form applied when the number of slave units is plural, and the plurality of slave units and the master unit perform wireless communication with each other, and the plurality of slave units have a plurality of slave units. Synchronize the imaging operation of each imaging device.

In a configuration including a plurality of slave units, the imaging operations of the imaging devices may not match, and the imaging time may be shifted. FIG. 17 is a schematic timing chart for explaining the imaging state of each imaging device of the plurality of slave units. When an imaging command signal (FIG. 17A) is transmitted from the master unit, each slave unit undergoes a processing operation based on the command signal, and then each imaging device executes an imaging operation to acquire image data. To do. The slave unit processes the image data and then transmits the data to the master unit. (FIGS. 17 (b) to 17 (d))

In each slave unit, a delay time occurs between the time when the command signal is transmitted and the time when the imaging operation is performed. This delay time is caused by, for example, a communication protocol (for example, TCP) between the master unit and the slave unit. Since this delay time differs for each slave unit depending on the communication environment and the like, there is a difference in the timing at which the imaging device of each slave unit performs the imaging operation.

In the measurement of displacement states such as deflection and strain of an imaged object such as a bridge, the time difference that occurs in the imaging operation of each imaging device causes a decrease in measurement accuracy, so simultaneity is required for imaging.

In the second aspect of the present invention, image data at simultaneous points is acquired by synchronizing the imaging operations of the imaging devices of the plurality of slave units.

(Cordless handset)
Each slave unit includes an image pickup device and a transmitter / receiver on the slave unit side. The imaging device included in each slave unit individually acquires a plurality of image data of the imaging target provided on the measurement target based on the command signal of the master unit. The slave unit-side transmitter / receiver included in each slave unit receives a command signal from the master unit and transmits image data and / or analysis data derived from the image data to the master unit.

(Master unit)
The master unit includes a transmission / reception unit on the master unit side and a displacement distribution analysis unit. The master unit transmission / reception unit transmits a command signal to the slave unit, and receives image data and / or analysis data from the slave unit. The displacement distribution analysis unit analyzes the displacement distribution of the measurement target from the displacement data.

(Slave unit or master unit)
The slave unit or the master unit includes an analysis unit that analyzes image data. Each slave unit simultaneously images each imaging target by each imaging device based on the synchronization trigger signal after receiving the command signal.

In the second aspect of the present invention, in each slave unit, the imaging device is imaged based on the synchronous trigger signal after receiving the command signal, so that each imaging device of the plurality of slave units synchronizes with the imaging operation. I do.

Synchronization of each imaging device of a plurality of slave units can be performed in a plurality of forms.

[First form of synchronization]
The first form of synchronization is a form in which a GPS signal is used as a synchronization trigger signal. Each slave unit generates a PPS signal based on a GPS signal received after establishing communication with the master unit, and synchronizes the imaging operation of each imaging device using the generated PPS signal as a synchronization trigger signal. Since the GPS signal received by each slave unit is irrelevant to the communication protocol between the master unit and the slave unit, it is not affected by the delay time by using the GPS signal received after the communication is established as a reference. Can be synchronized.

[Second form of synchronization]
The second form of synchronization is a form in which a synchronization trigger signal is transmitted from the master unit to each slave unit. The master unit generates a synchronization trigger signal after establishing communication with the slave unit, and simultaneously transmits the generated synchronization trigger to each slave unit. The synchronization signal can be transmitted from the master unit to each slave unit wirelessly without using a communication protocol, or may be transmitted by wire or optical communication. The occurrence of the delay time is suppressed by transmitting the synchronization signal without going through the communication protocol.

[Third form of synchronization]
The third form of synchronization is a form in which a synchronization trigger signal generated by one of the plurality of slave units is transmitted to the other slave units. One slave unit of a plurality of slave units generates a synchronization trigger signal after establishing communication with the master unit, and simultaneously transmits the generated synchronization trigger signal to another slave unit. The synchronization signal between the slave units may be transmitted wirelessly without using a communication protocol, or may be transmitted by wire or optical communication. The occurrence of the delay time is suppressed by transmitting the synchronization signal without going through the communication protocol.

[Fourth form of synchronization]
The fourth form of synchronization is a form in which each slave unit generates a synchronization trigger signal. After establishing communication with the master unit, each slave unit generates a synchronization trigger signal a predetermined time after receiving the command signal. The predetermined time from the reception of the command signal to the generation of the synchronization trigger signal is set longer than the delay time preset in each slave unit. Since the time point when this predetermined time elapses becomes a simultaneous point in each slave unit, the imaging operation is synchronized by using the synchronization trigger signal generated at this time point.

[Structure of analysis unit]
(First form of analysis unit)
The analysis unit of the first form is applied to the first form of the displacement measurement system provided in the slave unit or the master unit. The analysis unit of the first embodiment includes a displacement analysis unit that analyzes the displacement of the imaging target from the image data. The displacement analysis unit obtains analysis data by using sampling moire analysis on the image data, for example. This analysis data is displacement data representing the displacement of the measurement target. In the sampling moire analysis, the displacement of the imaging target is analyzed by comparing the image data acquired by imaging the imaging target with the reference data.

(Second form of analysis unit)
The analysis unit of the second form is applied to the master unit in the second form of the displacement measurement system including a plurality of slave units. The analysis unit of the second form includes a displacement analysis unit that analyzes the displacement of the imaging target from the image data and outputs the displacement data, and a displacement distribution analysis unit that analyzes the displacement distribution of the measurement target from the displacement data. The displacement analysis unit obtains the displacement data of each imaging target by using sampling moire analysis for the image data, for example, and the displacement distribution analysis unit obtains the displacement distribution data of the measurement target from the obtained displacement data of each imaging target. .. The displacement data of the displacement analysis unit and the displacement distribution data of the displacement distribution analysis unit of the analysis data are included.

[Image target, measurement target]
In the displacement measurement system of the present invention, for example, a bridge can be a measurement target, and a grid pattern provided on the measurement target as an imaging target is used. By applying sampling moire analysis to the image data of the captured image of this lattice pattern, the displacement of the imaging target is measured, and the displacement distribution of the measurement target is measured from the displacements of the plurality of imaging targets on the measurement target.

The displacement measurement system of the present invention may be configured to provide a light source that illuminates an imaging target such as a grid pattern. The imaging accuracy can be improved by illuminating the imaging target with a light source.

[Slave unit housing]
The slave unit included in the displacement measurement system of the present invention is housed in a waterproof, windproof, dustproof, etc. housing. The outer shape of this housing is dome-shaped or streamlined, thereby suppressing vibration due to wind.

According to the displacement measurement system of the present invention, it is possible to suppress blurring of the captured image caused by vibration of the camera due to the wind and noise components of the image data of the captured image. In addition, the measurement accuracy of displacement measurement can be improved.

FIG. 1 of the present invention is a schematic configuration diagram for explaining the displacement measurement system of the present invention. It is a timing chart which shows the operation outline of the displacement measurement system of this invention. It is a figure for demonstrating the housing of the slave unit of this invention. It is a figure for demonstrating the structure of the 1st structure example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 1st structure example of the displacement measurement system of this invention. It is a timing chart which shows the operation outline of the 1st configuration example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 2nd structural example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 2nd structural example of the displacement measurement system of this invention. It is a timing chart which shows the operation outline of the 2nd configuration example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 3rd configuration example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 3rd configuration example of the displacement measurement system of this invention. It is a timing chart which shows the operation outline of the 3rd configuration example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 4th structural example of the displacement measurement system of this invention. It is a timing chart which shows the operation outline of the 4th configuration example of the displacement measurement system of this invention. It is a figure for demonstrating the structure of the 5th structural example of the displacement measurement system of this invention. It is a timing chart which shows the operation outline of the 5th configuration example of the displacement measurement system of this invention. It is a timing chart for demonstrating the image processing of the displacement measurement system of this invention. It is a figure for demonstrating another configuration example of the displacement measurement system of this invention. It is a figure for demonstrating another configuration example of the slave unit of the displacement measurement system of this invention. This is an example of a system that measures the displacement of a bridge using image data captured by a conventional CCD camera. It is a timing chart which shows the operation outline of the system example which measures the displacement of a bridge using the image data imaged by the conventional CCD camera.

The displacement measurement system of the present invention will be described with reference to the drawings. Hereinafter, a schematic configuration example and an operation example of the displacement measurement system of the present invention will be described with reference to FIGS. 1 to 3, and a first embodiment of the displacement measurement system of the present invention will be described with reference to FIGS. 4 to 6. A second embodiment of the displacement measurement system of the present invention will be described with reference to FIGS. 9 to 9, a third embodiment of the displacement measurement system of the present invention will be described with reference to FIGS. 10 to 12, and the present invention will be described with reference to FIGS. 13 to 14. A fourth form of the displacement measurement system of the present invention will be described, and a fifth form of the displacement measurement system of the present invention will be described with reference to FIGS. 15 to 16.

(Approximate configuration and operation of the displacement measurement system of the present invention)
The schematic configuration of the displacement measurement system of the present invention will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram for explaining the displacement measurement system of the present invention.

The displacement measurement system of the present invention is a system that measures the displacement of the measurement target 1 such as a bridge. The displacement of the measurement target 1 is measured by imaging the image pickup target 2 attached to the measurement target 1 and analyzing the acquired image data. To measure. The image pickup target 2 can use a grid pattern or the like, and is mounted on the measurement target 1 such as a bridge at a position where the image pickup device can image. By using the retroreflective sheet as the grid pattern, it can be adapted to the measurement environment such as at night.

The imaging target 2 can be set at a single location or a plurality of locations on the measurement target 1. When the imaging target 2 is provided at a plurality of locations on the measurement target 1, the displacement distribution of the measurement target 1 can be measured together with the displacement of each position of the plurality of imaging targets 2. Further, when the imaging target 2 is provided at one location on the measurement target 1, the displacement of the position where the imaging target 2 is provided can be measured.

The displacement measurement system includes a slave unit 10 and a master unit 20 that perform wireless communication with each other. The wireless communication between the master unit 20 and the slave unit 10 is performed by protocol communication based on TCP. For this mutual communication, Wi-Fi communication or Bluetooth can be used. In Wi-Fi communication, the frequency band is 2.4 GHz or 920 MHz. The frequency used can be switched according to the environment around the measurement site.

The displacement measurement system communicates wirelessly between the slave unit and the master unit, so that the data acquired by the slave unit can be transmitted to the master unit without using a cable. In the configuration in which the cameras are connected by a cable, it is possible to suppress blurring of the captured image caused by the shaking of the cable and noise components of the image data of the captured image.

(Cordless handset)
The slave unit 10 includes a slave unit side transmission / reception unit 11, an image pickup device 12, and a power supply for the slave unit (not shown in FIG. 1), and is arranged and fixed in the vicinity of the measurement target 1. A plurality of slave units 10 can be provided, and each slave unit 10A to 10C includes a slave unit side transmission / reception unit 11, an image pickup device 12, and a power supply for the slave unit. Each of the slave units 10A to 10C is provided at a position where each of the imaging objects 2 provided at a plurality of long measurement objects such as a bridge is imaged. Although FIG. 1 shows the case of three slave units 10 as an example, the number of slave units is not limited to this number and can be arbitrary.

The displacement measurement system of the present invention is not limited to a single or a plurality of slave units, and the slave unit and the master unit communicate wirelessly with each other. However, when the number of slave units is multiple, a plurality of slave units are used. The slave unit and the master unit perform wireless communication with each other, and as will be described later, the plurality of slave units synchronize the imaging operation of each imaging device.

The slave unit side transmission / reception unit 11 performs wireless communication with the master unit 20 and receives a command signal from the master unit 20, and the image data acquired by the image pickup device 12 with respect to the master unit 20. And / or transmit the analysis data obtained by analyzing the image data. When the slave unit 10 transmits analysis data, the slave unit 10 includes an analysis unit 15 that obtains analysis data from the image data.

The analysis unit 15 includes a displacement analysis unit that analyzes the displacement of the imaging target from the image data, and outputs the displacement data of the displacement analysis unit as the analysis data.

The imaging device 12 starts the imaging process based on the command signal of the master unit 20, images the imaging target 2 provided on the measurement target 1, and acquires image data. In addition to transmitting the acquired image data, the slave unit side transmission / reception unit 11 transmits the analysis data obtained by analyzing the image data to the master unit 20.

When a plurality of image pickup devices 12 are provided, each image pickup device 12 of each slave unit 10 (10A to 10C) synchronizes the image pickup operation based on the synchronization trigger. By synchronizing the imaging operations of the imaging device 12 of each slave unit 10, each imaging target 2 of the measurement target 1 can be simultaneously imaged, and the displacement at the same point can be acquired.

(Master unit)
The master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply for the master unit (not shown in FIG. 1). The master unit 20 can be moved by mounting it on a vehicle or the like with respect to the fixed slave unit 10.

The master unit side transmission / reception unit 21 transmits a command signal to the slave unit 10 under the control of the command control unit 23, and receives image data and / or analysis data from the slave unit 10.

The analysis unit 22 included in the master unit 20 analyzes the displacement of the imaging target 2 from the image data and outputs the displacement data (not shown in FIG. 1), and analyzes the displacement distribution of the measurement target from the displacement data. It is provided with a displacement distribution analysis unit (not shown in FIG. 1). The analysis unit 22 outputs the displacement data of the displacement analysis unit and the displacement distribution data of the displacement distribution analysis unit as the analysis data.

(Measurement operation)
FIG. 2 is a timing chart showing an outline of operation of the displacement measurement system of the present invention. When a command signal is transmitted from the master unit, each slave unit (10A to 10C) receives this command signal and starts the imaging process. When mutual communication between the master unit and the slave unit is performed by wireless communication, for example, protocol communication based on TCP is performed. Wi-Fi communication or Bluetooth can be used for this mutual communication, but there is a delay time associated with the execution of the protocol until the communication is established. Since the delay time of each slave unit differs depending on the communication environment, even if each slave unit receives a command signal at the same time, the time when the imaging device of each slave unit actually starts the imaging operation differs depending on each delay time. ..

The displacement measurement system of the present invention uses a synchronous trigger signal in order to eliminate the start deviation of the imaging operation due to this delay time. The synchronization trigger signal is generated for each slave unit in consideration of a predetermined waiting time in addition to each delay time. The imaging device of each slave unit acquires an captured image at the same time by performing an imaging operation based on this synchronous trigger signal. The synchronization trigger signal can be set in consideration of the delay time in each slave unit, for example, by adding a margin to the delay time assumed to be the longest.

As the synchronization trigger signal, a time signal of a GPS signal can be used. The interval of the PPS signal generated from the GPS signal is 1 sec, and this time interval is sufficiently longer than the delay time assumed in the protocol processing, so that it can be used as a synchronous trigger signal. Further, since the GPS signal received by each slave unit is irrelevant to the communication protocol between the master unit and the slave unit, the delay time is affected by using the GPS signal received after the communication is established as a reference. It can be synchronized without any problems.
For example, the master unit instructs the imaging device to instruct the imaging start and imaging stop to the synchronous trigger generator, and the synchronous trigger generator includes the imaging start signal and the imaging stop signal generated by the GPS signal, including a computer. In addition to sending to the image pickup device, the master unit may send the image pickup start signal and the image pickup stop signal to the image pickup device including the computer.
Alternatively, the master unit transmits an imaging start and imaging stop signal to an imaging device including a computer, and the imaging signal including the computer is a signal of an imaging start signal and an imaging stop signal generated based on a GPS signal to a synchronous trigger generator. To request. The synchronous trigger generator transmits an imaging start signal and an imaging stop signal generated based on GPS signals to an imaging device including a computer.
As described above, in the embodiment of the present invention, since the GPS signal received by each slave unit is irrelevant to the communication protocol between the master unit and the slave unit, the GPS signal received after the communication is established is used as a reference. By doing so, synchronization can be performed without being affected by the delay time.

(Case shape of slave unit)
FIG. 3 is a diagram for explaining the housing of the slave unit. The slave unit of the present invention includes a housing having a dome-shaped or streamlined outer shape.

The housing 51A shown in FIG. 3A is an example of a dome-shaped outer shape, and a lens 50A of an imaging device is provided in a part of the housing. By making the outer shape dome-shaped, it is possible to reduce the shaking caused by the wind. The housing 51A is rotatable with respect to the base so that the lens 50A is brought closer to the imaging target.

The housings 51B and 51C shown in FIGS. 3B and 3C are examples of streamlined external shapes, and lenses 50B and 50C of an imaging device are provided in a part of the housing. By making the outer shape streamlined, it is possible to reduce the shaking caused by the wind.

Further, the housings 51A, 51B, and 51C can be prevented from invading the inside by having a waterproof structure and a dustproof structure in addition to the windproof structure.

Further, each housing can be made of metal, and is provided with an external antenna (not shown in the figure) for transmitting / receiving to / from the master unit and receiving GPS signals.

Hereinafter, a configuration example of the displacement measurement system of the present invention will be described. Hereinafter, the first configuration example to the fourth configuration example for synchronizing the imaging devices of the plurality of slave units will be described.

(First Configuration Example of Displacement Measurement System of the Present Invention)
A first configuration example of the displacement measurement system of the present invention will be described with reference to FIGS. 4 to 6.
The first configuration example is a form in which a GPS signal is used as a synchronization trigger signal. Each slave unit generates a PPS signal based on a GPS signal received after establishing communication with the master unit, and synchronizes the imaging operation of each imaging device using the generated PPS signal as a synchronization trigger signal.

FIGS. 4 and 5 are diagrams for explaining the configuration of the first configuration example of the displacement measurement system of the present invention, and the same reference numerals are used for components similar to the components shown in the schematic configuration of FIG. explain.

In the first configuration example, the displacement analysis unit that analyzes the image data for displacement and obtains the displacement data can be provided on the master unit side or on the slave unit side. The configuration example shown in FIG. 4 is a configuration example in which the displacement analysis unit is provided in the master unit, and the configuration example shown in FIG. 5 is a configuration example in which the displacement analysis unit is provided in the slave unit.

(Cordless handset)
In the configuration of FIG. 4, the slave unit 10 (10A, 10B, 10C) has the slave unit side transmission / reception unit 11, the image pickup device 12, the image pickup control unit 13, the image processing unit 14, the GPS signal reception unit 16, and the PPS signal generation unit 17. , A synchronous trigger signal generation unit 18, and a power supply 30 for a slave unit.

In the configuration of FIG. 5, the slave unit 10 (10A, 10B, 10C) has the slave unit side transmission / reception unit 11, the image pickup device 12, the image pickup control unit 13, the image processing unit 14, the analysis unit 15, the GPS signal reception unit 16, and the PPS. It includes a signal generation unit 17, a synchronous trigger signal generation unit 18, and a power supply 30 for a slave unit. Here, the slave unit 10A will be described as an example.

The slave unit side transmission / reception unit 11 includes a communication unit 11a and an image data transmission unit 11b. The communication unit 11a transmits and receives communication establishment signals such as RTS, CTS, and ACK with the master unit 20 in Wi-Fi communication, for example, to perform protocol communication. This communication establishment confirmation signal is an example, and is not limited to this. The RTS transmitted from the master unit side transmission / reception unit 21 to the slave unit side transmission / reception unit 11 corresponds to a command signal for causing each slave unit to perform imaging. The communication unit 11a of the transmission / reception unit 11 on the slave unit side performs wireless communication with the master unit 20 and receives a command signal from the master unit 20. The image data transmission unit 11b transmits the image data captured and acquired by the image pickup device 12 to the master unit 20, and the displacement data transmission unit 11c transmits the analysis data obtained by analyzing the image data to the master unit 20.

For example, a CCD camera can be used as the image pickup device 12, and the image pickup operation is performed by the signal from the image pickup control unit 13. The image processing unit 14 performs image processing on the signal obtained by the image pickup apparatus 12 to acquire image data.

As a configuration for synchronizing the imaging operation, a GPS signal receiving unit 16, a PPS signal generating unit 17, and a synchronous trigger signal generating unit 18 are provided. The GPS signal receiving unit 16 receives a GPS signal received by an antenna (not shown), and the PPS signal generating unit 17 generates a PPS signal based on a time signal included in the GPS signal. The synchronous trigger signal generation unit 18 generates a synchronous trigger signal using the PPS signal. The image pickup control unit 13 causes the image pickup device 12 to perform an image pickup operation as a synchronous trigger signal using the PPS signal.

In the transmission data transmitted from the slave unit 10 to the master unit 20, in the configuration shown in FIG. 4, the image data is transmitted from the image data transmission unit 11b of the slave unit side transmission / reception unit 11 to the master unit 20, and is shown in FIG. In the configuration, the displacement data transmission unit 11c of the slave unit side transmission / reception unit 11 transmits the displacement data to the master unit 20. The displacement data transmission unit 11c may transmit image data together with the displacement data when transmitting the displacement data.

When the slave unit acquires analysis data, the slave unit 10 includes an analysis unit 15 and a displacement data transmission unit 11c, as shown in FIG. The analysis unit 15 includes a displacement analysis unit 15a that analyzes the displacement of the imaging target from the image data, and a reference image data 15b. The displacement analysis unit 15a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data obtained by imaging and the reference image data 15b.

(Master unit)
In the configuration of FIG. 4, the master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply 40 for the parent / child unit. The master unit side transmission / reception unit 21 is an image data reception unit that receives image data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the image data transmission unit 11b of the slave unit 10. 21b is provided. The analysis unit 22 includes a displacement analysis unit 22a that analyzes the displacement of the imaging target from the image data received by the image data reception unit 21b, a reference image data 22b, and a displacement distribution analysis unit 22c. The displacement analysis unit 22a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data and the reference image data 22b. The displacement distribution analysis unit 22c analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target obtained by the displacement analysis unit 22a.

On the other hand, in the configuration of FIG. 5, the master unit 20 includes a master unit side transmission / reception unit 21, a displacement distribution analysis unit 22c, a command control unit 23, and a power supply 40 for the parent / child unit.

The master unit side transmission / reception unit 21 is a displacement data receiving unit that receives displacement data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the displacement data transmission unit 11c of the slave unit 10. 21d is provided. The analysis unit 22 includes a displacement distribution analysis unit 22c, and analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target transmitted from the slave unit 10.

(Measurement operation)
FIG. 6 is a timing chart showing an operation outline of the first configuration example of the displacement measurement system of the present invention.

When a command signal is transmitted from the master unit, each slave unit (10A to 10C) receives this command signal and starts the imaging process. When mutual communication between the master unit and the slave unit is performed by wireless communication, for example, protocol communication based on TCP is performed.

Each slave unit 10 (10A, 10B, 10C) constantly receives a GPS signal and generates a PPS signal. The GPS signal may be received and the PPS signal may be generated after the command signal is received from the master unit.

When each slave unit 10 receives a command signal from the master unit 20, it performs a protocol such as TCP with the master unit to perform communication establishment processing. For example, when the slave unit 10 requests communication from the master unit by RTS and communication is permitted from the master unit 20 to the slave unit 10 by CTS, the slave unit 10 sends an ACK to the master unit to perform communication. Establish. The delay time required for these communication protocols varies depending on each slave unit. In order to eliminate the timing shift of the imaging operation due to this delay time, a PPS signal generated from a GPS signal is used as a synchronization trigger signal for synchronizing the imaging operation. The time from the delay time to the synchronization trigger signal acts as a standby time, and by providing this standby time, the imaging operation is synchronized by the synchronization trigger signal.

When the image data or the like obtained in the imaging operation is transmitted from the slave unit to the master unit, the communication protocol is processed again, but the data transmission performed after this communication protocol does not require synchronization.

Since the GPS signal received by each slave unit is irrelevant to the communication protocol between the master unit and the slave unit, it is not affected by the delay time by using the GPS signal received after the communication is established as a reference. Can be synchronized.

(Second Configuration Example of Displacement Measurement System of the Present Invention)
A second configuration example of the displacement measurement system of the present invention will be described with reference to FIGS. 7 to 9.
The second configuration example is a form in which a synchronization trigger signal is transmitted from the master unit to each slave unit. The master unit generates a synchronization trigger signal after establishing communication with the slave unit, and simultaneously transmits the generated synchronization trigger to each slave unit. The synchronization signal can be transmitted from the master unit to each slave unit wirelessly without using a communication protocol, or may be transmitted by wire or optical communication. The occurrence of the delay time is suppressed by transmitting the synchronization signal without going through the communication protocol.

FIGS. 7 and 8 are diagrams for explaining the configuration of the second configuration example of the displacement measurement system of the present invention, and the same reference numerals are used for components similar to the components shown in the schematic configuration of FIG. explain.

In the second configuration example, the displacement analysis unit that analyzes the image data for displacement and obtains the displacement data can be provided on the master unit side or on the slave unit side. The configuration example shown in FIG. 7 is a configuration example in which the displacement analysis unit is provided in the master unit, and the configuration example shown in FIG. 8 is a configuration example in which the displacement analysis unit is provided in the slave unit.

(Cordless handset)
In the configuration of FIG. 7, the slave unit 10 (10A, 10B, 10C) includes a slave unit side transmission / reception unit 11, an image pickup device 12, an image pickup control unit 13, an image processing unit 14, and a power supply 30 for the slave unit.

In the configuration of FIG. 8, the slave unit 10 (10A, 10B, 10C) has the slave unit side transmission / reception unit 11, the image pickup device 12, the image pickup control unit 13, the image processing unit 14, the analysis unit 15, and the power supply 30 for the slave unit. To be equipped. Here, the slave unit 10A will be described as an example.

The slave unit side transmission / reception unit 11 includes a communication unit 11a, an image data transmission unit 11b (FIG. 7), a displacement data transmission unit 11c (FIG. 8), and a synchronous trigger reception unit 11d.

The communication unit 11a performs protocol communication with the master unit 20 in the same manner as in the first configuration example of the displacement measurement system. The RTS transmitted from the master unit side transmission / reception unit 21 to the slave unit side transmission / reception unit 11 corresponds to a command signal for causing each slave unit to perform imaging. The communication unit 11a of the transmission / reception unit 11 on the slave unit side performs wireless communication with the master unit 20 and receives a command signal from the master unit 20. The image data transmission unit 11b transmits the image data captured and acquired by the image pickup device 12 to the master unit 20, and the displacement data transmission unit 11c transmits the analysis data obtained by analyzing the image data to the master unit 20.

For example, a CCD camera can be used as the image pickup device 12, and the image pickup operation is performed by the signal from the image pickup control unit 13. The image processing unit 14 performs image processing on the signal obtained by the image pickup apparatus 12 to acquire image data.

As a configuration for synchronizing the imaging operation, a synchronous trigger receiving unit 11d for receiving a synchronous trigger signal transmitted from the master unit 20 is provided. The imaging control unit 13 causes the imaging device 12 to execute an imaging operation in synchronization with the synchronous trigger signal received by the synchronous trigger receiving unit 11d.

In the transmission data transmitted from the slave unit 10 to the master unit 20, in the configuration shown in FIG. 7, the image data is transmitted from the image data transmission unit 11b of the slave unit side transmission / reception unit 11 to the master unit 20, and is shown in FIG. In the configuration, the displacement data transmission unit 11c of the slave unit side transmission / reception unit 11 transmits the displacement data to the master unit 20. The displacement data transmission unit 11c may transmit image data together with the displacement data when transmitting the displacement data.

When the slave unit acquires analysis data, the slave unit 10 includes an analysis unit 15 and a displacement data transmission unit 11c, as shown in FIG. The analysis unit 15 includes a displacement analysis unit 15a that analyzes the displacement of the imaging target from the image data, and a reference image data 15b. The displacement analysis unit 15a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data obtained by imaging and the reference image data 15b.

(Master unit)
In the configuration of FIG. 7, the master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply 40 for the parent / child unit. The master unit side transmission / reception unit 21 is an image data reception unit that receives image data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the image data transmission unit 11b of the slave unit 10. It includes 21b and a synchronous trigger transmission unit 21c that generates and transmits a synchronous trigger signal. The analysis unit 22 includes a displacement analysis unit 22a that analyzes the displacement of the imaging target from the image data received by the image data reception unit 21b, a reference image data 22b, and a displacement distribution analysis unit 22c. The displacement analysis unit 22a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data and the reference image data 22b. The displacement distribution analysis unit 22c analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target obtained by the displacement analysis unit 22a.

On the other hand, in the configuration of FIG. 8, the master unit 20 includes a master unit side transmission / reception unit 21, a displacement distribution analysis unit 22c, a command control unit 23, and a power supply 40 for the parent / child unit.

The master unit side transmitting / receiving unit 21 is a displacement data receiving unit 21d that receives displacement data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the displacement data transmitting unit 11c of the slave unit 10. , And a synchronous trigger transmission unit 21c that generates and transmits a synchronous trigger signal. The analysis unit 22 includes a displacement distribution analysis unit 22c, and analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target transmitted from the slave unit 10.

The transmission / reception of the synchronization trigger signal between the synchronization trigger receiving unit 11d of the slave unit 10 and the synchronization trigger receiving unit 11d of the master unit 20 may be performed wirelessly without using a communication protocol, or may be performed by wired or optical communication. .. The occurrence of the delay time is suppressed by transmitting the synchronization signal without going through the communication protocol.

(Measurement operation)
FIG. 9 is a timing chart showing an operation outline of a second configuration example of the displacement measurement system of the present invention.

When a command signal is transmitted from the master unit, each slave unit (10A to 10C) receives this command signal and starts the imaging process. When mutual communication between the master unit and the slave unit is performed by wireless communication, for example, protocol communication based on TCP is performed.

When each slave unit 10 receives a command signal from the master unit 20, it performs a protocol such as TCP with the master unit to perform communication establishment processing. For example, when the slave unit 10 requests communication from the master unit by RTS and communication is permitted from the master unit 20 to the slave unit 10 by CTS, the slave unit 10 sends an ACK to the master unit to perform communication. Establish. The delay time required for these communication protocols varies depending on each slave unit. In order to eliminate the timing shift of the imaging operation due to this delay time, a synchronization trigger signal transmitted from the master unit is used as the synchronization trigger signal for synchronizing the imaging operation. The time from the delay time to the synchronization trigger signal acts as a standby time, and by providing this standby time, the imaging operation is synchronized by the synchronization trigger signal.

When the image data or the like obtained in the imaging operation is transmitted from the slave unit to the master unit, the communication protocol is processed again, but the data transmission performed after this communication protocol does not require synchronization.

Since the synchronization trigger signal received by each slave unit is irrelevant to the communication protocol between the master unit and the slave unit, it is delayed by referring to the synchronization trigger signal GPS signal received from the master unit after the communication is established. It can be synchronized without being affected by time.

(Third configuration example of the displacement measurement system of the present invention)
A third configuration example of the displacement measurement system of the present invention will be described with reference to FIGS. 10 to 12.
The third configuration example is a form in which a synchronization trigger signal generated by one of the plurality of slave units is transmitted to the other slave units. One slave unit of a plurality of slave units generates a synchronization trigger signal after establishing communication with the master unit, and simultaneously transmits the generated synchronization trigger signal to another slave unit. The synchronization signal between the slave units may be transmitted wirelessly without using a communication protocol, or may be transmitted by wire or optical communication. The occurrence of the delay time is suppressed by transmitting the synchronization signal without going through the communication protocol.

10 and 11 are diagrams for explaining the configuration of the third configuration example of the displacement measurement system of the present invention, and the same reference numerals are used for components similar to the components shown in the schematic configuration of FIG. explain.

In the third configuration example, the displacement analysis unit that obtains the displacement data by performing the displacement analysis of the image data can be provided on the master unit side or the slave unit side. The configuration example shown in FIG. 10 is a configuration example in which the displacement analysis unit is provided in the master unit, and the configuration example shown in FIG. 11 is a configuration example in which the displacement analysis unit is provided in the slave unit.

(Cordless handset)
In the configuration of FIG. 10, the slave unit 10 (10A, 10B, 10C) includes a slave unit side transmission / reception unit 11, an image pickup device 12, an image pickup control unit 13, an image processing unit 14, and a power supply 30 for the slave unit.

In the configuration of FIG. 11, the slave unit 10 (10A, 10B, 10C) has the slave unit side transmission / reception unit 11, the image pickup device 12, the image pickup control unit 13, the image processing unit 14, the analysis unit 15, and the power supply 30 for the slave unit. To be equipped. Here, the slave unit 10A will be described as an example.

The slave unit side transmission / reception unit 11 includes a communication unit 11a, an image data transmission unit 11b (FIG. 10), a displacement data transmission unit 11c (FIG. 11), and a synchronous trigger transmission unit 11e.

The communication unit 11a performs protocol communication with the master unit 20 in the same manner as in the second configuration example of the displacement measurement system. The RTS transmitted from the master unit side transmission / reception unit 21 to the slave unit side transmission / reception unit 11 corresponds to a command signal for causing each slave unit to perform imaging. The communication unit 11a of the transmission / reception unit 11 on the slave unit side performs wireless communication with the master unit 20 and receives a command signal from the master unit 20. The image data transmission unit 11b transmits the image data captured and acquired by the image pickup device 12 to the master unit 20, and the displacement data transmission unit 11c transmits the analysis data obtained by analyzing the image data to the master unit 20.

For example, a CCD camera can be used as the image pickup device 12, and the image pickup operation is performed by the signal from the image pickup control unit 13. The image processing unit 14 performs image processing on the signal obtained by the image pickup apparatus 12 to acquire image data.

As a configuration for synchronizing the imaging operation, a synchronous trigger transmitting unit 11e is provided in which a synchronous trigger signal is generated in one of the slave units and the synchronous trigger signal is transmitted to the other slave unit, and the synchronous trigger signal is received in the other slave unit. A synchronous trigger receiving unit 11d is provided. Here, the slave unit 10A is provided with the synchronous trigger transmitting unit 11e, and the slave units 10B and 10C are provided with the synchronous trigger receiving unit 11d. The imaging control unit 13 of the slave unit 10A causes the imaging device 12 to execute an imaging operation in synchronization with the synchronous trigger signal transmitted by the synchronous trigger transmitting unit 11e, and the imaging control unit 13 of the slave units 10B and 10C receives the synchronous trigger. The imaging device 12 is made to execute the imaging operation in synchronization with the synchronization trigger signal received by the unit 11d.

In the transmission data transmitted from the slave unit 10 to the master unit 20, in the configuration shown in FIG. 10, the image data is transmitted from the image data transmission unit 11b of the slave unit side transmission / reception unit 11 to the master unit 20, and is shown in FIG. In the configuration, the displacement data transmission unit 11c of the slave unit side transmission / reception unit 11 transmits the displacement data to the master unit 20. The displacement data transmission unit 11c may transmit image data together with the displacement data when transmitting the displacement data.

When the slave unit acquires analysis data, the slave unit 10 includes an analysis unit 15 and a displacement data transmission unit 11c, as shown in FIG. The analysis unit 15 includes a displacement analysis unit 15a that analyzes the displacement of the imaging target from the image data, and a reference image data 15b. The displacement analysis unit 15a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data obtained by imaging and the reference image data 15b.

(Master unit)
In the configuration of FIG. 10, the master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply 40 for the parent / child unit. The master unit side transmission / reception unit 21 is an image data reception unit that receives image data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the image data transmission unit 11b of the slave unit 10. 21b is provided. The analysis unit 22 includes a displacement analysis unit 22a that analyzes the displacement of the imaging target from the image data received by the image data reception unit 21b, a reference image data 22b, and a displacement distribution analysis unit 22c. The displacement analysis unit 22a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data and the reference image data 22b. The displacement distribution analysis unit 22c analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target obtained by the displacement analysis unit 22a.

On the other hand, in the configuration of FIG. 11, the master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply 40 for the parent / child unit.

The master unit side transmission / reception unit 21 is a displacement data receiving unit 21d that receives displacement data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the displacement data transmission unit 11c of the slave unit 10. To be equipped. The analysis unit 22 includes a displacement distribution analysis unit 22c, and analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target transmitted from the slave unit 10.

Transmission and reception of the synchronization trigger signal between the synchronization trigger transmission unit 11e of the slave unit 10 (10A) and the synchronization trigger reception unit 11d of the slave unit 10 (10B, 10C) is performed wirelessly without using a communication protocol, and is also wired. Alternatively, it may be performed by optical communication. The occurrence of the delay time is suppressed by transmitting the synchronization signal without going through the communication protocol.

(Measurement operation)
FIG. 12 is a timing chart showing an operation outline of a third configuration example of the displacement measurement system of the present invention.

When a command signal is transmitted from the master unit, each slave unit (10A to 10C) receives this command signal and starts the imaging process. When mutual communication between the master unit and the slave unit is performed by wireless communication, for example, protocol communication based on TCP is performed.

When each slave unit 10 receives a command signal from the master unit 20, it performs a protocol such as TCP with the master unit to perform communication establishment processing. For example, when the slave unit 10 requests communication from the master unit by RTS and communication is permitted from the master unit 20 to the slave unit 10 by CTS, the slave unit 10 sends an ACK to the master unit to perform communication. Establish. The delay time required for these communication protocols varies depending on each slave unit. In order to eliminate the timing shift of the imaging operation due to this delay time, a synchronization trigger signal generated by the slave unit is used as the synchronization trigger signal for synchronizing the imaging operation. The time from the delay time to the synchronization trigger signal acts as a standby time, and by providing this standby time, the imaging operation is synchronized by the synchronization trigger signal.

When the image data or the like obtained in the imaging operation is transmitted from the slave unit to the master unit, the communication protocol is processed again, but the data transmission performed after this communication protocol does not require synchronization.

Since the synchronization trigger signal is transmitted by one slave unit and transmitted to another slave unit, it has nothing to do with the communication protocol between the master unit and the slave unit. As a result, the synchronization trigger signal received from the master unit after the communication is established can be synchronized without being affected by the delay time by using the PPS signal as a reference.

(Fourth Configuration Example of Displacement Measurement System of the Present Invention)
A fourth configuration example of the displacement measurement system of the present invention will be described with reference to FIGS. 13 to 14.
The fourth configuration example is a form in which each slave unit generates a synchronous trigger signal. After establishing communication with the master unit, each slave unit generates a synchronization trigger signal a predetermined time after receiving the command signal. The predetermined time from the reception of the command signal to the generation of the synchronization trigger signal is set longer than the delay time preset in each slave unit. Since the time point when this predetermined time elapses becomes a simultaneous point in each slave unit, the imaging operation is synchronized by using the synchronization trigger signal generated at this time point.

FIG. 13 is a diagram for explaining the configuration of a fourth configuration example of the displacement measurement system of the present invention, and components similar to the components shown in the schematic configuration of FIG. 1 will be described using the same reference numerals. ..

In the fourth configuration example, the displacement analysis unit that analyzes the image data for displacement and obtains the displacement data can be provided on the master unit side as well as on the slave unit side. The configuration example shown in FIG. 13 is a configuration example in which the displacement analysis unit is provided in the master unit. Although the configuration example in which the displacement analysis unit is provided in the slave unit is omitted, it can be the same as the configuration examples of the first, second, and third displacement measurement systems.

(Cordless handset)
In the configuration of FIG. 13, the slave unit 10 (10A, 10B, 10C) is used for the slave unit side transmission / reception unit 11, the image pickup device 12, the image pickup control unit 13, the image processing unit 14, the synchronous trigger generation unit 19, and the slave unit. A power supply 30 is provided. Here, the slave unit 10A will be described as an example.

The slave unit side transmission / reception unit 11 includes a communication unit 11a and an image data transmission unit 11b. The communication unit 11a performs protocol communication with the master unit 20 in the same manner as in the second configuration example of the displacement measurement system. The RTS transmitted from the master unit side transmission / reception unit 21 to the slave unit side transmission / reception unit 11 corresponds to a command signal for causing each slave unit to perform imaging. The communication unit 11a of the transmission / reception unit 11 on the slave unit side performs wireless communication with the master unit 20 and receives a command signal from the master unit 20. The image data transmission unit 11b transmits the image data imaged and acquired by the image pickup apparatus 12 to the master unit 20.

For example, a CCD camera can be used as the image pickup device 12, and the image pickup operation is performed by the signal from the image pickup control unit 13. The image processing unit 14 performs image processing on the signal obtained by the image pickup apparatus 12 to acquire image data.

Each slave unit 10 includes a synchronization trigger generation unit 19 as a configuration for synchronizing the imaging operation. Each slave unit 10 individually generates a synchronization trigger signal in the synchronization trigger generation unit 19 provided therein. The synchronization trigger signal is generated after a set time set from the time when the communication unit 11a receives the received command signal. The set time for generating the synchronization trigger signal is set to be longer than the delay time caused by the communication protocol or the like.

The image pickup control unit 13 of each of the slave units 10A, 10B, and 10C causes the image pickup device 12 to execute the image pickup operation in synchronization with the synchronization trigger signal generated by the respective synchronization trigger generation units 19.

In the transmission data transmitted from the slave unit 10 to the master unit 20, the image data transmission unit 11b of the slave unit side transmission / reception unit 11 transmits the image data to the master unit 20, and the displacement data transmission of the slave unit side transmission / reception unit 11 The displacement data may be transmitted from the unit to the master unit. The displacement data transmission unit may transmit image data together with the displacement data when transmitting the displacement data.

When the slave unit acquires the analysis data, the slave unit 10 includes an analysis unit and a displacement data transmission unit. The analysis unit includes a displacement analysis unit that analyzes the displacement of the imaged object from the image data, and reference image data. The displacement analysis unit outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data obtained by imaging and the reference image data.

(Master unit)
In the configuration of FIG. 13, the master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply 40 for the master unit. The master unit side transmission / reception unit 21 is an image data reception unit that receives image data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the image data transmission unit 11b of the slave unit 10. 21b is provided. The analysis unit 22 includes a displacement analysis unit 22a that analyzes the displacement of the imaging target from the image data received by the image data reception unit 21b, a reference image data 22b, and a displacement distribution analysis unit 22c. The displacement analysis unit 22a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data and the reference image data 22b. The displacement distribution analysis unit 22c analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target obtained by the displacement analysis unit 22a.

The synchronization trigger signal generated by the synchronization trigger generation unit 19 of each slave unit 10 (10A, 10B, 10C) is performed without going through the communication protocol, so that the occurrence of delay time is suppressed.

(Measurement operation)
FIG. 14 is a timing chart showing an operation outline of a fourth configuration example of the displacement measurement system of the present invention.

When a command signal is transmitted from the master unit, each slave unit (10A to 10C) receives this command signal and starts the imaging process. When mutual communication between the master unit and the slave unit is performed by wireless communication, for example, protocol communication based on TCP is performed.

When each slave unit 10 receives a command signal from the master unit 20, it performs a protocol such as TCP with the master unit to perform communication establishment processing. For example, when the slave unit 10 requests communication from the master unit by RTS and communication is permitted from the master unit 20 to the slave unit 10 by CTS, the slave unit 10 sends an ACK to the master unit to perform communication. Establish. The delay time required for these communication protocols varies depending on each slave unit. In order to eliminate the timing shift of the imaging operation due to this delay time, a synchronization trigger signal generated by each slave unit is used as the synchronization trigger signal for synchronizing the imaging operation. The time from the delay time to the synchronization trigger signal acts as a standby time, and by providing this standby time, the imaging operation is synchronized by the synchronization trigger signal.

(Fifth configuration example of the displacement measurement system of the present invention)
A fifth configuration example of the displacement measurement system of the present invention will be described with reference to FIGS. 15 to 16.
The fifth configuration example is a form in which a synchronization signal is generated in each slave unit among the plurality of slave units. The synchronization signal of each slave unit is synchronized between each slave unit. The synchronization deviation of the synchronization signal between the slave units can be synchronized and adjusted by the PPS signal obtained from the GPS signal.

FIG. 15 is a diagram for explaining the configuration of a fifth configuration example of the displacement measurement system of the present invention, and components similar to the components shown in the schematic configuration of FIG. 11 will be described using the same reference numerals. ..

In the fifth configuration example, the displacement analysis unit that obtains the displacement data by performing the displacement analysis of the image data can be provided on the master unit side or the slave unit side. In the following, the configuration example shown in FIG. 15 describes a configuration example in which the displacement analysis unit is provided in the slave unit.

(Cordless handset)
In the configuration of FIG. 15, the slave unit 10 (10A, 10B, 10C) has the slave unit side transmission / reception unit 11, the image pickup device 12, the image pickup control unit 13, the image processing unit 14, the analysis unit 15, the GPS signal reception unit 16, and the PPS. It includes a signal generation unit 17 and a power supply 30 for a slave unit. Here, the slave unit 10A will be described as an example.

The slave unit side transmission / reception unit 11 includes a communication unit 11a, a displacement data transmission unit 11c, and a synchronization signal generation unit 11f.

The communication unit 11a performs protocol communication with the master unit 20. The RTS transmitted from the master unit side transmission / reception unit 21 to the slave unit side transmission / reception unit 11 corresponds to a command signal for causing each slave unit to perform imaging. The communication unit 11a of the transmission / reception unit 11 on the slave unit side performs wireless communication with the master unit 20 and receives a command signal from the master unit 20. The displacement data transmission unit 11c transmits the analysis data obtained by analyzing the image data to the master unit 20. The synchronization signal generation unit 11f generates a synchronization signal for synchronizing the timing of acquiring the captured image of each slave unit, and sends the synchronization signal to the imaging control unit 13.

The image pickup control unit 13 of the slave unit 10A causes the image pickup device 12 to execute an image pickup operation in synchronization with the synchronization signal generated by the synchronization signal generation unit 11f. Similarly for the slave units 10B and 10C, the image pickup control unit causes the image pickup device to execute the image pickup operation in synchronization with the synchronization signal generated by the synchronization signal generation unit 11f.

The synchronization signal generation unit 11f of each slave unit generates, for example, a periodic signal generated by an oscillation circuit using a crystal oscillator as a synchronization signal. This synchronization signal has a period of, for example, 1/100 second or 1/200 second. The period of the synchronization signal can be set arbitrarily, but by setting the period to be sufficiently shorter than the PPS signal, high-speed imaging can be performed as compared with the case where the PPS signal is used as the synchronization signal.

The synchronization signal generation unit 11f of each slave unit may cause a cycle deviation in the synchronization signal due to a frequency deviation of the oscillation cycle of the built-in oscillation circuit. In order to eliminate the period shift of the synchronization signal, the synchronization signal generation unit 11f of each slave unit performs synchronization adjustment based on the PPS signal. The synchronization adjustment is performed based on the PPS signal of the PPS signal generation unit 17. FIG. 16 is a diagram for explaining synchronization adjustment. The cycle deviation of the synchronization signals (FIGS. 16B to 16d) of the slave units A, B, and C is synchronously adjusted according to the PPS signal. The synchronization adjustment by the PPS signal (FIG. 16A) can be performed once for several PPS signals, but may be performed for each cycle of the PPS signal if necessary. In FIG. 16A, the PPS signal used for synchronization adjustment is shown in black.

For example, a CCD camera can be used as the image pickup device 12, and the image pickup operation is performed by the signal from the image pickup control unit 13. The image processing unit 14 performs image processing on the signal obtained by the image pickup apparatus 12 to acquire image data.

In the transmission data transmitted from the slave unit 10 to the master unit 20, in the configuration shown in FIG. 15, the displacement data transmission unit 11c of the slave unit side transmission / reception unit 11 transmits the displacement data to the master unit 20. The displacement data transmission unit 11c may transmit image data together with the displacement data when transmitting the displacement data.

When the slave unit acquires analysis data, the slave unit 10 includes an analysis unit 15 and a displacement data transmission unit 11c. The analysis unit 15 includes a displacement analysis unit 15a that analyzes the displacement of the imaging target from the image data, and a reference image data 15b. The displacement analysis unit 15a outputs displacement data representing the displacement state of the imaging target by sampling moire analysis based on the image data obtained by imaging and the reference image data 15b.

(Master unit)
In the configuration of FIG. 15, the master unit 20 includes a master unit side transmission / reception unit 21, an analysis unit 22, a command control unit 23, and a power supply 40 for the parent / child unit. The master unit side transmission / reception unit 21 is a displacement data receiving unit that receives displacement data transmitted from the communication unit 21a that performs protocol communication with the communication unit 11a of the slave unit 10 and the displacement data transmission unit 11c of the slave unit 10. 21d is provided. The analysis unit 22 includes a displacement distribution analysis unit 22c, and analyzes the displacement distribution of the measurement target based on the displacement data of each imaging target transmitted from the slave unit 10.

(Measurement operation)
The operation of the fifth configuration example of the displacement measurement system of the present invention can be performed in the same manner as the operation shown in the third configuration example.

When a command signal is transmitted from the master unit, each slave unit (10A to 10C) receives this command signal and starts the imaging process. When mutual communication between the master unit and the slave unit is performed by wireless communication, for example, protocol communication based on TCP is performed.

When each slave unit 10 receives a command signal from the master unit 20, it performs a protocol such as TCP with the master unit to perform communication establishment processing. For example, when the slave unit 10 requests communication from the master unit by RTS and communication is permitted from the master unit 20 to the slave unit 10 by CTS, the slave unit 10 sends an ACK to the master unit to perform communication. Establish. The delay time required for these communication protocols varies depending on each slave unit. In order to eliminate the timing shift of the imaging operation due to this delay time, a synchronization signal generated by each slave unit is used as a synchronization signal for synchronizing the imaging operation. The time from the delay time to the synchronization signal acts as a standby time, and by providing this standby time, the imaging operation is synchronized by the synchronization signal.

When the data obtained by the imaging operation is transmitted from the slave unit to the master unit, the processing of the communication protocol is performed again, but the data transmission performed after this communication protocol does not require synchronization.

Since the synchronization signal is generated in each slave unit, it has nothing to do with the communication protocol between the master unit and the slave unit. Further, since the synchronization signal of each slave unit is synchronized with the PPS signal, the synchronization signal can be synchronized with the PPS signal as a reference without being affected by the delay time.

(Image processing)
In each configuration example of the displacement measurement system of the present invention, the imaging data acquired in each imaging can be image-processed for each imaging, or a plurality of imaging data can be collectively image-processed. Image processing of a plurality of captured data is performed based on a start signal instructing the start of image processing from the master unit and an end signal for ending image processing. An example of collectively performing image processing on a plurality of captured data will be described with reference to FIG.

The master unit sends an imaging start signal and an imaging stop signal to each slave unit as command signals for commanding the start and stop of imaging (FIG. 17A).

When each of the slave units A, B, and C receives the imaging start signal (FIG. 17 (a)) sent from the master unit, each of the synchronization signals (FIGS. 17 (b), (e) generated after receiving the start signal. ), (H)), and the imaging data at each synchronization signal is acquired (FIGS. 17 (c), (f), (i)). Next, when the imaging stop signal (FIG. 17 (a)) sent from the master unit is received, image processing of the plurality of acquired imaging data is performed (FIGS. 17 (d), (g), (j). )).

By performing image processing after imaging the plurality of imaging data, a sufficient processing time for image processing can be secured, so that image processing can be performed without being restricted by the periodic interval of the synchronization signal. Further, since the captured image can be limited between the imaging start signal and the imaging stop signal, it is possible to avoid acquiring an unnecessary captured image.

When the image data or the like obtained in the imaging operation is transmitted from the slave unit to the master unit, the communication protocol is processed again, but the data transmission performed after this communication protocol does not require synchronization.

Since the synchronous trigger signal is generated by each slave unit and does not require transmission / reception, it is irrelevant to the communication protocol between the master unit and the slave unit. Therefore, the synchronous trigger signal GPS signal received from the master unit after communication is established. By using the above as a reference, synchronization can be performed without being affected by the delay time.

(Other configuration examples of displacement measurement system)
For mutual communication between the master unit and the slave unit, Wi-Fi communication or Bluetooth may be used, or an Internet network may be used. FIG. 18 shows a schematic configuration of mutual communication using an Internet network. Mutual communication between the master unit and each slave unit A, B, C is performed via the Internet network.

(Other configuration examples of the slave unit)
As shown in FIG. 19, the slave unit 10 is provided with a vibration determination unit 61, and when it is determined that a vibration different from the normal vibration is generated, it is determined that some load is applied to the displacement measurement target, and the master unit is used. Send vibration detection to. When the master unit receives a vibration detection signal from the slave unit, it commands each slave unit to perform synchronized imaging.

FIG. 19 is a diagram for explaining another configuration example of the slave unit. When the displacement measurement target is a bridge, the vibration determination unit 61 detects the approach of a train or vehicle passing through the bridge, and sends a preliminary signal to the master unit to start the displacement measurement. As a result, unnecessary displacement measurement can be avoided.

The vibration data used for the vibration determination of the vibration determination unit 61 may be acquired by a separately provided deflection detection unit 60, or may be acquired from image data obtained by constantly performing imaging. The imaging at this time does not need to be synchronized with each slave unit, and image data captured at an arbitrary cycle can be used.

Further, the constant deflection measurement may be performed as follows. The technical matters are described in detail in JP-A-2018-28439.

In Japanese Unexamined Patent Publication No. 2018-28439, the first line image data of one line in the displacement analysis direction is extracted from the image of the measurement object obtained by imaging before the displacement of the measurement object, and the measurement object is described. The second line image data of one line in the displacement analysis direction is extracted from the image of the measurement object obtained by imaging after the displacement of, and one-dimensional Fourier is added to the first line image data and the second line image data, respectively. The transformation is performed, and among the spatial frequency components obtained by the one-dimensional Fourier transformation, the spatial frequency component corresponding to the measurement object is subjected to phase analysis by the one-dimensional inverse Fourier transformation, and the phase analysis is performed before and after the displacement. A method of measuring the displacement amount of the object to be measured by using the phase difference is disclosed.

Further, in Japanese Patent Application Laid-Open No. 2018-28439, the first line image data of one line in the displacement analysis direction is extracted from the image of the measurement object obtained by imaging before the displacement of the measurement object, and the measurement is performed. The second line image data of one line in the displacement analysis direction is extracted from the image of the measurement object obtained by imaging after the displacement of the object, and the first line image data and the second line image data are Fouriered. The components of the real and imaginary parts of the spectrum are obtained for each spatial frequency using conversion, and the feature value calculated from the phase value and power obtained by using the components of the real and imaginary parts for each of the frequency components is calculated. Then, the phase difference before and after the deformation is obtained by using the phase value, and the weighted average of the displacements for each spatial frequency is used by using the weight value calculated from the feature value calculated from the power for each frequency component. Displacement is disclosed as a method of calculating the displacement amount of the measurement object by using the coefficient of the actual displacement amount with respect to the change of the coordinate value in the image of the measurement object.

Then, the image pickup device may be a displacement measurement system that takes a picture based on a synchronization signal generated by the slave unit.

The master unit has a shooting start button, and when the shooting start button is pressed down, a shooting start command is output from the master unit to the slave unit, synchronization is performed by the slave unit, and shooting is performed by the imaging device. It may be started.

The master unit has a shooting end button, and when the shooting end button is pressed down, a command to end shooting is output from the master unit, synchronized with the slave unit, and photographed by the imaging device. It may be a displacement measurement system in which

The slave unit constantly performs a deflection measurement on the object, and when a signal other than normal vibration is detected by the constant deflection measurement, the displacement measurement determines that a moving body is approaching the object. It may be a system.

The slave unit may be a displacement measurement system having a function of transmitting information to the master unit via the Internet.

The description in the above-described embodiments and modifications is an example of the displacement measurement system according to the present invention, and the present invention is not limited to each embodiment, and various modifications are made based on the gist of the present invention. It is possible, and these are not excluded from the scope of the present invention.

The displacement measurement system of the present invention can be applied not only to the displacement measurement of a bridge but also to the displacement measurement of a structure installed outdoors in a long horizontal direction and a vertical direction.

1 Measurement target 2 Imaging target 3 Light source 4 Power supply 10, 10A, 10B, 10C Slave unit 11 Slave unit side transmitter / receiver 11a Communication unit 11b Image data transmission unit 11c Displacement data transmission unit 11d Synchronous trigger receiver 11e Synchronous trigger transmitter 11f Synchronous Signal generation unit 12 Imaging device 13 Imaging control device 14 Image processing unit 15 Analysis unit 15a Displacement analysis unit 15b Reference image data 16 GPS signal reception unit 17 PPS signal generation unit 18 Synchronous trigger signal generation unit 19 Synchronous trigger generation unit 20 Master unit 21 Master unit side transmission / reception unit 21a Communication unit 21b Image data reception unit 21c Synchronous trigger transmission unit 21d Displacement data reception unit 22 Analysis unit 22a Displacement analysis unit 22b Reference image data 22c Displacement distribution analysis unit 23 Command control unit 30 Power supply 40 Power supply 50 Lens 51 Housing 60 Deflection detection unit 61 Vibration determination unit

Claims (11)

Equipped with multiple slave units and a master unit that communicates wirelessly with each slave unit
Each of the slave units
Based on image data of a plurality of imaging target provided on the measurement object to the command signal before Symbol parent unit receives the command signal from the imaging device and the parent device to be acquired in the individual, the image data to the master unit and / or Image data analysis The transmitter / receiver on the slave unit that transmits data and
With
The master unit is
Transmitting the command signal to the slave unit, and the base-side transceiver unit image data or for receiving analysis data from the slave unit,
It is equipped with a displacement distribution analysis unit that analyzes the displacement distribution of the measurement target from the analysis data.
The slave unit or the master unit includes an analysis unit that analyzes the analysis data from the image data.
Wherein each slave unit, displacement distribution measurement system the command signal on the basis of the synchronization trigger signal after receiving, and wherein the simultaneously imaged to Rukoto each imaging target by the respective imaging devices. Each of the slave units
The displacement distribution measurement system according to claim 1, wherein a PPS signal is generated based on a GPS signal received after communication with the master unit is established, and the PPS signal is used as the synchronous trigger signal . The master unit is
The displacement distribution measurement system according to claim 1, wherein the synchronous trigger signal is generated after communication with the slave unit is established, and the synchronous trigger is simultaneously transmitted to each slave unit . One slave unit of the plurality of slave units is
The displacement distribution measurement system according to claim 1, wherein the synchronous trigger signal is generated after communication with the master unit is established, and the synchronous trigger signal is simultaneously transmitted to another slave unit . Each of the slave units
The displacement distribution measurement system according to claim 1, wherein a synchronous trigger signal is generated after a predetermined time from the reception of the command signal after the communication with the master unit is established . The analysis unit included in the master unit
It is provided with a displacement analysis unit that analyzes the displacement of the imaging target from the image data and outputs the displacement data, and a displacement distribution analysis unit that analyzes the displacement distribution of the measurement target from the displacement data.
The displacement distribution measurement system according to any one of claims 1 to 5, wherein the analysis data includes the displacement data of the displacement analysis unit and the displacement distribution data of the displacement distribution analysis unit . The displacement distribution measurement system according to any one of claims 1 to 6, wherein the mutual communication between the master unit and the slave unit is communication based on TCP . The displacement distribution measurement system according to claim 7, wherein the mutual communication is a wireless LAN communication or a short-distance data communication of a digital device . The displacement distribution measurement system according to any one of claims 1 to 6, wherein the image pickup target is a grid pattern provided on the measurement target . The displacement distribution measurement system according to any one of claims 1 to 9, further comprising a light source that illuminates the image pickup target . The slave unit displacement distribution measurement system according to claim 1, any one of 10 the external shape, characterized in that it comprises a housing shaped domed or streamline.