JP2018031589A - Geomorphometry system - Google Patents

Abstract

Provided is a terrain measurement system capable of measuring a wide area with high density at low cost even on terrain with few feature points.
The terrain measurement system according to the present invention is configured such that the communication terminal is installed by associating a result of a laser ranging device measuring a distance to the communication terminal installed on the terrain with a unique ID of the communication terminal. Identify the terrain variation at the location.
[Selection] Figure 1A

Description

  The present invention relates to a system for measuring terrain.

  In order to detect signs of landslides at an early stage, technology for measuring a wide range of topographic shapes with high accuracy is important. Specifically, (a) a method of arranging a GPS (Global Positioning System) terminal in a measurement target area, (b) a method of arranging a prism for laser ranging in the measurement target area, and the like have been used. In addition, LiDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) is also known as a measurement technique.

  The following Patent Document 1 describes a technique for measuring terrain variation using a laser distance measuring device. The following Patent Document 2 describes a technique for monitoring terrain fluctuation on a slope without setting a target by using a boulder or a collapsed surface as a mark.

JP 2007-170821 A JP2012-083237A

  As described in Patent Document 1, in a method of measuring the terrain using a laser range finder, it is common to install a GPS terminal or a prism in order to improve measurement accuracy. However, since these devices are expensive, there is a limit to arranging these devices at a high density in a wide measurement area.

  The technique described in Patent Document 2 aims to measure the terrain without installing a target. However, in the same document, since topographical changes are measured using a boulder or a collapsed surface as a landmark, it is considered difficult to accurately measure such topographical changes with few feature points.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a terrain measurement system that can measure a wide area at high density at low cost even with terrain with few feature points. And

  The terrain measurement system according to the present invention relates to the position where the communication terminal is installed by associating the result of the laser ranging device measuring the distance to the communication terminal installed on the terrain with the unique ID of the communication terminal. Identify terrain fluctuations.

  According to the terrain measurement system according to the present invention, even in terrain with few feature points, it is possible to accurately detect terrain fluctuations while suppressing costs by identifying the displacement of each communication terminal.

1 is a configuration diagram of a terrain measurement system 10 according to Embodiment 1. FIG. It is a figure which shows a mode that the landslide 301 generate | occur | produced in the topography 300. FIG. 2 is a configuration diagram showing an outline of a communication terminal 200. FIG. 3 is a configuration diagram of a control circuit 230. FIG. 3 is a time chart for explaining an operation procedure of the terrain measurement system 10. It is a time chart explaining the communication procedure between the some communication terminals 200. FIG.

<Embodiment 1>
FIG. 1A is a configuration diagram of a terrain measurement system 10 according to Embodiment 1 of the present invention. The terrain measurement system 10 is a system that measures the terrain variation of the terrain 300. The terrain measurement system 10 includes a flying object 100 and a communication terminal 200.

  The flying object 100 is a UAV (Unmanned Aerial Vehicles) that is equipped with a laser distance measuring device 110 and a reader device 120 and is controlled by radio control. The laser distance measuring device 110 measures the distance to the irradiation position 112 by irradiating a plurality of irradiation positions 112 on the terrain 300 with the laser light 111 and detecting the reflected light. The reader device 120 performs wireless communication with the communication terminal 200 installed on the terrain 300 via the electromagnetic wave 121.

  The communication terminal 200 is installed at a plurality of positions on the terrain 300. The position and number of communication terminals 200 are not necessarily matched with the position and number of irradiation positions 112. In FIG. 1A, 18 communication terminals 200 are installed, and numbers for convenience (corresponding to unique IDs described later) are assigned.

  FIG. 1B is a diagram illustrating a state in which a landslide 301 has occurred on the terrain 300. The landslide 301 is a phenomenon in which the ground surface shifts. When a large landslide occurs, it is considered that the deviation is measured as a three-dimensional terrain change, and it is relatively easy to detect this. On the other hand, a landslide in such a manner that the surface shape of the terrain 300 does not change greatly can be considered. In this case, since the measurement result by laser ranging within the measurement target range does not greatly differ before and after the occurrence of the landslide 301, it is difficult to measure the topographic change due to the landslide only by laser ranging. Even if the terrain deformation that can be measured by laser ranging occurs, if the location where the terrain deformation occurs is outside the measurement target range, it is still difficult to measure the terrain variation.

  Therefore, in the first embodiment, by identifying each communication terminal 200 individually, the landform change at the position where each communication terminal 200 is installed is specified. For example, in the example shown in FIG. 1B, since the third communication terminal 200 has moved from the initial installation position, it can be specified that a terrain change has occurred at that position. Thereby, even if the shape of the ground surface itself does not change, it is possible to measure the topographic change due to the landslide 301.

  FIG. 2 is a configuration diagram illustrating an outline of the communication terminal 200. An antenna 220, a control circuit 230, and a sensor 240 are disposed on the substrate 210. The antenna 220 wirelessly communicates with the reader device 120 via the electromagnetic wave 121. The control circuit 230 has each circuit described later. The sensor 240 detects the laser light emitted by the laser distance measuring device 110.

  The electric power necessary for the operation of the control circuit 230 and the sensor 240 can be supplied from the reader device 120 through the electromagnetic wave 121, or can be supplied from a battery provided in the communication terminal 200 itself. The electromagnetic wave 121 also has a role of transmitting / receiving a control signal from the reader device 120, communication data transmitted from the antenna 220 to the reader device 120, and the like.

  FIG. 3 is a configuration diagram of the control circuit 230. The control circuit 230 includes a power supply circuit 231, a transmission / reception circuit 232, a processing circuit 233, an AD converter 234, and a storage unit 235. The power supply circuit 231 uses the power transmitted via the electromagnetic wave 121 to generate a current having a predetermined voltage that is used for the operation of the communication terminal 200. The transmission / reception circuit 232 encodes the communication data 123 transmitted to the reader apparatus 120 via the antenna 220 or decodes the control signal 122 received from the reader apparatus 120 via the antenna 220. The processing circuit 233 controls the transmission / reception circuit 232. The AD converter 234 converts an analog signal into a digital signal. The storage unit 235 stores a unique ID uniquely assigned to the communication terminal 200.

  FIG. 4 is a time chart for explaining the operation procedure of the terrain measurement system 10. Hereinafter, a communication procedure between the devices of the terrain measurement system 10 and a procedure for measuring the terrain variation will be described with reference to FIG.

  The reader device 120 transmits a control signal 122 that instructs the communication terminal 200 to start measurement. When receiving the control signal 122, the communication terminal 200 shifts to an operation mode in which the laser beam 111 is received.

  The laser distance measuring device 110 emits a laser beam 111. When the communication terminal 200 is installed at the irradiation position of the laser beam 111, the sensor 240 detects the laser beam 111. The communication terminal 200 stores data indicating that the laser beam 111 has been detected in the storage unit 235.

  The reader device 120 transmits a control signal 122 that instructs the communication terminal 200 to transmit the detection result of the laser beam 111. In response to the control signal 122, the communication terminal 200 returns communication data 123 describing the detection of the laser beam 111 and the unique ID of the communication terminal 200.

  The reader device 120 can individually identify the communication terminal 200 installed at the position irradiated with the laser beam 111 based on the unique ID described in the communication data 123. The terrain measurement system 10 can specify the change with time of the position of the communication terminal 200 having the same unique ID by repeating the same procedure at different times. That is, when the reader device 120 specifies the change in the position of the same communication terminal 200, the change in the terrain at the position where the communication terminal 200 is installed can be specified.

  FIG. 5 is a time chart for explaining a communication procedure with a plurality of communication terminals 200. The laser distance measuring device 110 and the reader device 120 sequentially perform the operation procedure described with reference to FIG. By associating the position irradiated with the laser beam 111 with the unique ID of the communication terminal 200, each communication terminal 200 can be individually identified and the topographic change of the installation position can be specified.

<Embodiment 1: Summary>
The terrain measurement system 10 according to the present embodiment 1 individually identifies the communication terminal 200 using the unique ID of the communication terminal 200 installed on the terrain 300, so that the measurement result and individual communication by the laser distance measuring device 110 are identified. The terminal 200 is associated. Thereby, the terrain change in the position where the communication terminal 200 is installed can be specified.

  In the landform measurement system 10 according to the first embodiment, the communication terminal 200 can be configured as an inexpensive passive terminal (a terminal that uses the received electromagnetic wave 121 as operating power). Thereby, many communication terminals 200 can be arrange | positioned, suppressing cost. Furthermore, even if a part of the communication terminal 200 includes a battery, the cost of the terrain measurement system 10 as a whole can be suppressed.

<Embodiment 2>
In the second embodiment of the present invention, a case will be described in which a plurality of communication terminals 200 are installed within a range in which the reader device 120 can perform wireless communication at a time. Since the other configuration is the same as that of the first embodiment, the individual identification of a plurality of communication terminals 200 installed mainly in the communication range of the reader device 120 will be described below.

  The reader device 120 performs wireless communication within a range having a certain extent. Then, a plurality of communication terminals 200 may be installed within a range where the reader device 120 communicates at the same time. In this case, there is a possibility that the laser distance measuring device 110 irradiates all of the communication terminals 200 with the laser beam 111 during the period in which the reader device 120 performs wireless communication simultaneously with each communication terminal 200. Then, after the reader device 120 collects the unique ID of each communication terminal 200, when trying to associate each unique ID with the measurement result by the laser distance measuring device 110, the unique ID that can be associated with the laser distance measurement result. Therefore, it is necessary to further distinguish these unique IDs.

  Therefore, each communication terminal 200 may also describe the time when the laser beam 111 is received in the communication data 123. Accordingly, the reader device 120 associates the time when the laser distance measuring device 110 transmits the laser beam 111 with the time when the communication terminal 200 receives the laser beam 111, so that the collected unique ID is set at any irradiation position. It can be specified whether the communication terminal 200 is used.

  However, in this case, it is necessary to synchronize the clock provided in the laser distance measuring device 110 with the clock provided in the communication terminal 200. Clock synchronization may be performed in advance, or may be performed by an appropriate method such as any device (for example, the reader device 120) instructing the synchronization timing.

<Embodiment 2: Summary>
In the landform measurement system 10 according to the second embodiment, the laser distance measuring device 110, the reader device 120, and the communication terminal 200 can include clocks synchronized with each other. The communication terminal 200 transmits the time when the laser beam 111 is received to the reader device 120 as communication data 123. As a result, the reader apparatus 120 can identify which communication terminal 200 has received the communication data 123 even when communicating simultaneously with the plurality of communication terminals 200.

<Modification of the present invention>
The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  In the above embodiment, the example in which the UAV (aircraft 100) is equipped with the laser distance measuring device 110 and the reader device 120 has been described. Can also be installed.

  In the above embodiment, the communication terminal 200 can be configured by forming each circuit block on the substrate 210 or can be configured by attaching inexpensive discrete components. For example, it is advantageous in terms of cost if the sensor 240 and the antenna 220 are configured by discrete components.

  In the above embodiment, it has been described that the communication data 123 transmitted by the communication terminal 200 and the measurement result by the laser distance measuring device 110 are collected in the reader device 120. However, other devices connected to the reader device 120 ( For example, the data may be collected on a storage device included in a computer. For example, by wirelessly transmitting data from the flying object 100 to another device, the data can be collected on the device.

  In the above embodiment, optical noise other than the laser light 111 (for example, sunlight noise) may be incident on the sensor 240. Therefore, the sensor 240 can be configured to detect only an optical signal that has been subjected to predetermined modulation. The laser distance measuring device 110 can suppress the possibility that the sensor 240 detects noise by irradiating the laser beam 111 after modulating the laser beam 111 in advance. Similarly, the sensor 240 can be configured to detect only an optical signal within a predetermined frequency range.

10: Terrain measurement system 100: flying object 110: laser distance measuring device 120: reader device 200: communication terminal 210: substrate 220: antenna 230: control circuit 240: sensor

Claims (8)

A terrain measurement system that measures changes in the shape of terrain,
A communication terminal installed on the terrain,
A reader device for wireless communication with the communication terminal;
A laser distance measuring device that measures the distance to the communication terminal by irradiating the communication terminal with laser light;
Have
The communication terminal includes a sensor that detects the laser light, and a communication unit that wirelessly communicates with the reader device.
When the sensor detects the laser light, the communication unit transmits a unique ID of the communication terminal to the reader device,
The reader device associates the unique ID transmitted by the communication unit with the distance to the communication terminal measured by the laser distance measuring device, so that the shape of the terrain at the position where the communication terminal is installed A topographic measurement system characterized by identifying changes. The laser distance measuring device and the communication terminal each have a clock synchronized with each other,
The communication unit, together with the unique ID, transmits the time when the sensor detects the laser beam to the reader device,
The reader device refers to the unique ID transmitted by the communication unit by referring to the time when the laser distance measuring device irradiates the communication terminal with the laser light and the time received from the communication unit. The terrain measurement system according to claim 1, wherein the distance to the communication terminal measured by the laser range finder is associated. The reader device is configured to perform wireless communication simultaneously with the plurality of communication terminals,
The laser range finder irradiates each of the plurality of communication terminals with the laser beam while the reader device is wirelessly communicating with the plurality of communication terminals simultaneously.
3. The reader device identifies the received unique ID from which of the plurality of communication terminals that perform wireless communication at the same time by referring to the time received from the communication unit. The terrain measurement system described. The laser distance measuring device irradiates the same communication terminal with the laser light at different times,
The reader device uses the distance to the communication terminal measured by the laser range finder at each of the different times to identify the shape change of the terrain at the position where the same communication terminal is installed. The terrain measurement system according to claim 1. The terrain measurement system according to claim 1, wherein the communication terminal is configured as a passive terminal that uses electromagnetic waves transmitted by the reader device as electric power. The terrain measurement system according to claim 1, wherein the communication terminal includes a battery that supplies operating power. The terrain measurement system according to claim 1, wherein the sensor is configured to respond only to an optical signal subjected to predetermined modulation or an optical signal having a frequency within a predetermined range. The terrain measurement system according to claim 1, wherein the reader device and the laser distance measuring device are mounted on a flying object controlled by radio control.

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