JP2019039868A - Information processing device, information processing method and program for information processing - Google Patents

Abstract

To provide an information processing device capable of accurately acquiring the ground altitude of an aircraft.SOLUTION: The information processing device for an unmanned aircraft, comprises: an aircraft position acquisition part configured to acquire a three-dimensional position Pof a flying UAV (unmanned aircraft 200); a ground position acquisition part configured to acquire a piece of data of a ground position Pcorresponding to the position of the flying UAV on the basis of laser scan data to the ground corresponding to the P; and a ground altitude calculation part configured to calculate the ground altitude of the aircraft on the basis of a difference between the Pand the P.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for performing processing related to an altitude of an aircraft.

  A technique using an unmanned aerial vehicle (UAV (Unmanned Aerial Vehicle)) for aerial photogrammetry is known. In this technique, the accuracy of the UAV's ground altitude (altitude from the ground surface) is important. As a technique for specifying the three-dimensional position of a UAV, there is a method of tracking a flying UAV with a TS (total station) (see, for example, Patent Document 1). In this method, the UAV is tracked using the target tracking function provided in the TS, and the position of the UAV flying is specified using the laser distance measuring function provided in the TS.

US2014 / 0210663 Publication

  When GNSS is used, altitude from the average sea level with high accuracy can be acquired by relative positioning. However, in the first place, the land to be surveyed has insufficient data on its fine elevation, and it is not possible to expect a high-accuracy ground level. The same applies to the case where a TS is used. Even if the three-dimensional position of the UAV is specified by the TS, the accuracy of the ground height cannot be obtained unless the altitude of the ground surface directly below the UAV is accurately known. In addition, at civil engineering construction sites, the topography changes due to construction, and the elevation of the ground surface may not be known accurately. Also in this case, it is difficult to obtain an accurate ground altitude.

  In such a background, an object of the present invention is to provide a technique for accurately acquiring the ground altitude of an aircraft.

According to one aspect of the present invention, the aircraft position acquisition unit that acquires three-dimensional position P ₁ of the aircraft flying, based on laser scan data for the surface corresponding to the P _1, corresponding to the position of the aircraft to the flight is an information processing apparatus according to an unmanned aircraft comprising a ground position acquiring unit that acquires data of surface positions P _2, and a ground height calculation unit for calculating the ground height of the aircraft based on the difference of the P ₁ and the P ₂ .

  According to a second aspect of the present invention, in the first aspect of the invention, a future position prediction unit that predicts a future position of the aircraft based on a flight plan of the aircraft and / or a flight trajectory of the aircraft, and the future position And a scan range setting unit for setting a scan range for acquiring the laser scan data.

  According to a third aspect of the present invention, in the invention according to the first or second aspect, in order to perform flight control for reducing a difference between a ground altitude calculated by the ground altitude calculating unit and a predetermined ground altitude. And a control signal generator for generating the control signal.

The invention of claim 4 is the invention according to claim 1, wherein the surface position acquisition unit, the coordinates of a plurality of points surrounding the position of the P ₂ in the laser scan data Based on the above, the ground altitude is calculated.

Invention of claim 5 is the invention according to any one of claims 1 to 4, the position of the P ₁ is the position of the flight plan, the ground altitude, position of the flight plan It is a value.

The invention according to claim 6, the aircraft position acquisition step of acquiring a three-dimensional position P ₁ of the aircraft flying, based on laser scan data for the surface corresponding to the P _1, corresponding to the position of the aircraft to the flight is an information processing method according to the unmanned aircraft comprising a ground position obtaining step of obtaining data of surface positions P _2, and a ground height calculation step of calculating the P ₁ and the P of the aircraft based on a difference ₂ AGL .

The invention of claim 7 is a program to be executed is read by the computer, and the aircraft position acquisition unit that acquires three-dimensional position P ₁ of the aircraft flying computer, laser for surface corresponding to the P ₁ Based on scan data, a ground surface position acquisition unit that acquires data of a ground surface position P ₂ corresponding to the position of the flying aircraft, and a ground height that calculates the ground height of the aircraft based on the difference between the P ₁ and the P ₂ It is an information processing program that functions as a calculation unit.

According to the present invention, it is possible to obtain a technique for accurately obtaining the ground altitude of an aircraft.

It is a conceptual diagram of embodiment. It is a block diagram of an embodiment. It is a flowchart which shows an example of the procedure of the process of embodiment. It is a conceptual diagram of embodiment. It is a block diagram of an embodiment. It is a conceptual diagram of embodiment. It is a block diagram of an embodiment.

1. First embodiment (configuration)
FIG. 1 shows a conceptual diagram of the embodiment. FIG. 1 shows a flying UAV 200 and a TS (total station) 100 installed on the ground. The UAV 200 includes a camera 201 and performs shooting for aerial photogrammetry while flying.

  The TS 100 measures the three-dimensional position of the UAV 200 using ranging light while tracking the flying UAV 200. The UAV 200 is tracked by searching for the reflecting prism 202 provided in the UAV 200 using search light. The position of the UAV 200 is measured by irradiating the reflecting prism 202 with distance measuring light and detecting the reflected light. Done in Further, the TS 100 performs calculation for calculating the ground altitude of the flying UAV 200 and setting the ground altitude of the flying UAV 200 to a specified value.

  The flight of the UAV 200 includes a form of autonomous flight according to a flight plan and a form of being operated by a pilot's remote operation. In the case of aerial photogrammetry, flight is often performed in accordance with a predetermined flight plan in order to perform shooting efficiently and without leakage, but flight by manual operation is also possible.

  The UAV 200 is a commercially available model and is not special. The UAV 200 includes a control system for flight, a GNSS position measurement device, a wireless communication device, a storage device for storing a flight plan and a flight log, and an altimeter.

  At the lower part of the UAV 200, a reflection prism 202 that is a target for surveying by the TS 100 is attached. Further, the UAV 200 is equipped with a camera 201, and photographs the ground surface from the air.

  TS100 uses its own position measurement device using GNSS, a camera that acquires an image of a survey target (UAV200), a search laser scan function that searches for a target (reflection prism 202 of UAV200), and a distance measuring laser beam. Laser distance measurement function for measuring the distance to the target (reflecting prism 202), function for measuring the direction of the target (horizontal angle and vertical angle (elevation angle or depression angle)), and distance and direction to the target It has a function to calculate the three-dimensional position of the target, a function to communicate with an external device, and a laser scan function to obtain point cloud data.

  By measuring the distance and direction to the target, the position of the target with respect to TS100 can be measured. Here, if the position of the TS 100 is known, the position (latitude / longitude / altitude or XYZ coordinates on the orthogonal coordinate system) of the target (in this case, the UAV 200) in the map coordinate system can be known. This function is a function of a commercially available TS and is not special. Techniques relating to TS are described in, for example, Japanese Unexamined Patent Application Publication Nos. 2009-229192 and 2012-202821. Note that the map coordinate system is a coordinate system that handles map information (for example, latitude, longitude, altitude (elevation)). For example, position information obtained by GNSS is usually described in a map coordinate system.

  Hereinafter, an example of the TS 100 used in the present embodiment will be described. FIG. 2 shows a block diagram of TS100. The TS 100 includes a camera 101, a target searching unit 102, a distance measuring unit 103, a horizontal / vertical direction detecting unit 104, a horizontal / vertical direction driving unit 105, a data storage unit 106, a position measuring unit 107, a communication device 108, and a target position calculating unit. (UAV position calculation unit) 109, UAV tracking control unit 111, laser scanner 112, control microcomputer 113, UAV position data acquisition unit 114, laser scan data acquisition unit 115, UAV corresponding ground surface position acquisition unit 116, UAV ground height calculation unit 117, a UAV future position prediction unit 118, a laser scan range setting unit 119, and a flight control signal generation unit 120.

  Each functional unit shown in FIG. 2 may be configured by dedicated hardware, or a component that can be configured by software using a microcomputer may be configured by software. As hardware used to realize the configuration of FIG. 2, various electronic devices (for example, a camera module configuring the camera 101, a wireless module configuring the communication device 108, and the like), various driving using a motor, etc. Examples include a mechanism, a sensor unit, an optical component, various electronic circuits, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), and an FPGA (Field Programmable Gate Array). The above hardware configuration is the same for the UAV 200.

  The camera 101 captures a moving image or a still image of a survey target such as the UAV 200 or a target. The camera 101 is configured using a camera module using a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The camera 101 shoots a positioning target (for example, UAV200) via a telescope, and the image data is captured. obtain. Usually, an operator performs an approximate collimation of a target to be surveyed using an image captured by the camera 101 through a telescope, and then performs an accurate collimation of the target by an autonomous operation by an automatic tracking function. .

  The optical axis of the camera 101 coincides with the optical axis of the distance measuring unit 103 described later (the optical axis of the distance measuring laser beam), and the target for specifying the position is captured at the center of the captured image of the camera 101. . The TS 100 includes a small display (for example, a liquid crystal display), and an image captured by the camera 101 can be displayed there. Data of images taken by the camera 101 can be output to the outside and displayed on an appropriate display.

  It is also possible to use a commercially available digital camera as the camera 101 and attach it to the TS 100 externally. Data of an image captured by the camera 101 can be stored in an appropriate storage area in association with data such as a measurement time, a measurement direction, a measurement distance, and a position of the measurement object related to the distance measurement object.

  The target search unit 102 searches for a target (a reflection prism 202 of the UAV 200) using a search laser beam having a triangular pyramid or fan beam. The target search is performed using TS100 as a reference position. A technique for searching for a target is described in, for example, Japanese Patent No. 5124319.

  The distance measuring unit 103 measures the distance to the target using the distance measuring laser beam. The distance measuring unit 103 includes a light emitting element for distance measuring laser light, an irradiation optical system, a light receiving optical system, a light receiving element, a distance calculating unit, and an optical path for reference light. The distance to the object is calculated from the phase difference between the distance measuring light reflected from the object and the reference light. The method for calculating the distance is the same as that for normal laser ranging.

  The horizontal / vertical direction detection unit 104 measures the horizontal direction angle and the vertical direction angle (elevation angle and depression angle) of the target measured by the distance measurement unit 103. The housing portion including the optical system of the target search unit 102, the distance measurement unit 103, and the camera 101 can be controlled in horizontal rotation and elevation angle (decline angle), and the horizontal direction angle and the vertical direction angle are measured by an encoder. . The output of the encoder is detected by the horizontal / vertical direction angle detection unit 104, and the horizontal direction angle and the vertical direction angle (elevation angle and depression angle) are measured.

  The horizontal / vertical direction driving unit 105 includes a motor that performs horizontal rotation and elevation angle control (and depression angle control) of a housing portion including the optical system of the target search unit 102, the distance measurement unit 103, and the camera 101, and a drive circuit for the motor And a control circuit for the drive circuit. Note that a laser scanner 112, which will be described later, is also disposed in this housing portion. The data storage unit 106 stores a control program necessary for the operation of the TS 100, various data, survey results, and the like.

  The position measuring unit 107 measures the position of the TS 100 using GNSS. The position measuring unit 107 can perform both relative positioning and single positioning. In an environment where relative positioning is possible, measurement of the position of TS100 using relative positioning is preferable. However, when relative positioning is difficult, the position of TS100 is measured by independent positioning. Usually, the TS 100 is often left at a known position. In this case, the position measuring unit 107 is not necessary.

  The communication device 108 communicates with an external device. The TS 100 can be operated by an external terminal (dedicated terminal, PC, tablet, smartphone, etc.), and communication at this time is performed using the communication device 108. In addition, the communication device 108 receives various data necessary for the operation of the TS 100 and outputs various data acquired by the TS 100 to the outside. For example, the TS 100 can acquire various information related to surveying by accessing a data server that handles map information and terrain information from the TS 100 via the Internet line. In addition, a configuration in which some of the functions illustrated in FIG. 2 are performed by an external device is possible, and in this case, various types of data are exchanged via the communication device 108. The communication device 108 transmits a control signal for performing flight control to the UAV 200 toward the UAV 200.

  The target position calculation unit 109 calculates the position (coordinates) of the target with respect to the TS 100 from the distance and direction to the target (in this case, the reflecting prism 202 mounted with the UAV 200). Here, the distance to the target is obtained by the distance measuring unit 103, and the direction of the target is obtained by the horizontal / vertical direction detecting unit 104. Since the position of the TS 100 serving as the reference position is specified by the position measuring unit 107, the position of the target in the map coordinate system can be obtained by obtaining the position of the target with respect to the TS 100.

  The UAV tracking control unit 111 performs control for tracking the supplemented UAV. That is, the optical axis direction of the TS 100 is controlled in correspondence with the incident direction of the tracking light (tracking light reflected from the UAV 200) detected by the target search unit 102, so that the optical axis of the TS 100 is always directed to the UAV 200 moving in the air. The dynamic control is performed by the UAV tracking control unit 111. Specifically, the incident direction of the tracking light reflected from the target (reflecting prism 202) with respect to TS100 is detected, and based on the detected direction, the optical axis of TS100 (the optical axis of the distance measuring light from distance measuring unit 103) is set at the position of reflecting prism 202. ) Is always performed by the UAV tracking control unit 111 so as to output a control signal to the horizontal / vertical direction driving unit 105.

  The laser scanner 112 obtains point cloud data by using the distance measuring laser light as scanning light. The point cloud data is data that captures an object as a set of points whose three-dimensional coordinates are known. In this example, the target search unit 102 and the laser scanner 112 have different configurations, and the laser scanner 112 operates separately from the target search unit 102. Here, the wavelength of the laser light used by the laser scanner is selected to be different from the laser light used by the target search unit 102 so as not to interfere with the laser light used by the target search unit 102. Laser scanners for obtaining point cloud data are described in, for example, Japanese Patent Application Laid-Open Nos. 2010-151682, 2008-268004, US Pat. No. 8,767,190, and US Pat. No. 7,969,558.

  Hereinafter, the laser scanner 112 will be described. The laser scanner 112 is a distance measuring laser beam irradiation unit, a light receiving unit that receives the distance measuring laser beam reflected from the object, and a distance measuring unit that detects the distance to the object based on the flight time of the distance measuring laser beam. And a distance measuring direction detector for detecting the irradiation direction (ranging direction) of the distance measuring laser beam. Further, the laser scanner 112 includes a position calculation unit for a distance measurement target point that calculates a three-dimensional position of a reflection point of the distance measurement laser light based on its own position, distance measurement distance, and distance measurement direction. A scan control unit for controlling the irradiation direction and the light receiving direction of the reflected light (the optical axis of the distance measuring light) is provided.

  The distance measuring laser light is output in pulses at a specific repetition frequency, and irradiated to a specific range in a point while being scanned. The distance from the flight time of the laser beam for distance measurement to the reflection point is calculated. Usually, the distance to the object is calculated from the phase difference between the reference light flying in the reference optical path provided in the apparatus and the distance measuring light irradiated to the object and reflected from the object. A three-dimensional position with the origin of the position of the laser scanner 112 at the reflection point is calculated from the distance measured, the irradiation direction of the laser light for distance measurement, and the position of the laser scanner 112. Point cloud data can be obtained by measuring a number of positions of the reflection points. Here, the position and orientation of the laser scanner 112 in the TS 100 are acquired in advance as known information, and the position of the laser scanner 112 in the map coordinate system is calculated based on the positioning data of the position measuring unit 107. Therefore, the three-dimensional coordinates in the map coordinate system of each scanned point (reflection point) can be acquired.

  The distance measuring laser light is scanned and irradiated at a specific oscillation frequency, whereby the three-dimensional coordinates of each of a number of reflection points on the object are acquired. A set of a large number of reflection points on this object becomes point cloud data. In the point cloud data, an object is captured as a set of points whose three-dimensional positions are specified.

  The laser scanner 112 can acquire the reflection intensity and RGB intensity of the reflected light from the reflection point. The RGB intensity is obtained by selecting the reflected light with an R filter, a G filter, and a B filter and detecting the light intensity of each color. Therefore, data on the RGB intensity of each point of the obtained point cloud data is also obtained. In addition, it is not limited to RGB, The form which acquires the intensity | strength of one or several specific color information is also possible.

  The control microcomputer 113 controls the processing procedure of FIG. 3 described later and the operation of the entire TS 100. The UAV position data acquisition unit 114 acquires the position data (longitude, latitude, altitude, or three-dimensional coordinate values in an appropriate coordinate system) of the target (reflecting prism 202) calculated by the target position calculation unit 109 as the position of the UAV 200. To do. The altitude at this stage is a value based on the average sea level. As the position of the UAV 200 acquired by the UAV position data acquisition unit 114, a value based on the positioning data of the GSNN position specifying device mounted on the UAV 200 may be used. In this case, in order to ensure accuracy, it is preferable to perform positioning of the UAV 200 by relative positioning using GNSS.

  The laser scan data acquisition unit 115 acquires point cloud data acquired by the laser scanner 112. The coordinates of each point in the point cloud data are specified by (longitude, latitude, altitude, or three-dimensional coordinate values in an appropriate coordinate system). The altitude in the point cloud data is also based on the average sea level. A laser scanner may be prepared separately, and the laser scan data obtained there may be acquired by the laser scan data acquisition unit 115.

The UAV corresponding ground position acquisition unit 116 acquires the position (longitude / latitude or two-dimensional coordinate position in an appropriate coordinate system) of the ground surface corresponding to the position of the UAV 200 based on the point cloud data acquired by the laser scanner 112. . The position of the ground surface corresponding to the position of the UAV 200 is the position of the ground surface vertically below the UAV 200. For example, it is assumed that the three-dimensional position of the UAV 200 at a certain time acquired by the position data acquisition unit 114 is (X ₁ , Y ₁ , Z ₁ ). In this case, the UAV corresponding ground position acquisition unit 116 performs processing for acquiring the point (X ₁ , Y ₁ , Z ₂ ) at the coordinates of (X ₁ , Y ₁ ) from the point cloud data acquired by the laser scanner 112. Done.

Here, Z ₁ is the sea level altitude of UAV 200, and Z ₂ is the sea level altitude of the ground surface directly below UAV 200. As will be described later, Z ₁ -Z ₂ is the ground altitude of the UAV 200 (the altitude from the ground surface).

By the way, the point cloud data obtained by the laser scanner is data obtained by acquiring the three-dimensional position of each point. In the above case, the point cloud completely corresponds to the position of (X ₁ , Y ₁ ). There are cases where data cannot be obtained. Therefore, the following processing is performed to obtain a point corresponding to (X ₁ , Y ₁ ) from the point cloud data.

First, an allowable threshold value is set, and points corresponding to (X ₁ , Y ₁ ) are extracted from the point cloud data within a range equal to or smaller than this threshold value. When there is no point cloud data in the range below the threshold, an area including a point (point of coordinates (X ₁ , Y ₁ )) designated as a point immediately below the UAV 200 is set, and a plurality of points are selected therefrom. Then, an average value of the Z values of a plurality of selected points to it to the value of Z _2. The above processing is performed by the UAV corresponding ground surface position acquisition unit 116.

The UAV ground altitude calculation unit 117 calculates the ground altitude of the UAV 200. Specifically, the UAV 200 altitude (height relative to the average sea level) Z ₁ acquired by the UAV position data acquisition unit 114 and the corresponding altitude of the ground surface directly below the UAV 200 (height relative to the average sea level) calculating the difference between Z ₂ and _(Z 1 -Z ₂₎ as AGL.

Hereinafter, an example of specific processing performed by the UAV ground altitude calculation unit 117 will be described. For example, it is assumed that the three-dimensional position of the UAV 200 at a certain time t ₁ acquired by the position data acquisition unit 114 is P1 (X ₁ , Y ₁ , Z ₁ ). In this case, the corresponding position P2 of the ground surface (the coordinates of the ground surface vertically below P1) is (X ₁ , Y ₁ ). Then, from the point cloud data acquired by the laser scan data acquisition unit 115, a position where the coordinates of the latitude and longitude coincide with (X ₁ , Y ₁ ) or closest is searched, and the Z value (Z ₂ ) of the corresponding point is searched. ) (The height from the average sea level at position P2 (elevation)). Next, Z ₁ -Z ₂ is calculated, and the ground altitude at time t ₁ of the UAV 200 is obtained.

The UAV future position prediction unit 118 predicts the position of the UAV 200 at a future time based on the flight plan and / or the flight trajectory, and acquires the position. First, the prediction of the future position based on the flight plan will be described. In this case, first, the position P ₀ of the UAV 200 at the time t ₀ when the prediction is performed is acquired from the output of the target position calculation unit 109. Next, the position Pt of the UAV 200 at the future time t is calculated from the flight plan with P ₀ as the origin.

  Next, a case where the position of the UAV 200 at a future time is predicted based on the flight trajectory will be described. First, the flight path (flight trajectory) data of the UAV 200 before that time is acquired from the output of the target position calculation unit 109. Next, it is predicted that the future will fly according to the acquired flight route, and the position of the UAV 200 at the expected time is calculated. For example, if the UAV was in a straight flight at that time (the time at which prediction is performed), it is assumed that the straight flight will be continued as it is, and the position of the UAV 200 at the future time is predicted. Also, for example, if the UAV is making a turn flight at that time, it is assumed that the turn will continue and the position of the UAV 200 at a future time is predicted. Note that the concept of flight trajectory includes the speed at that time (speed and direction: speed vector).

  The future position may be predicted using information on both the flight plan and the flight trajectory. In this case, first, a past flight trajectory is acquired, applied to the flight plan, and a subsequent flight path is predicted. Based on the predicted flight path, the position of the UAV 200 at a future time is predicted.

  The laser scan range setting unit 119 sets the scan range of the laser scanner 112 based on the future position of the UAV 200 predicted by the UAV future position prediction unit 118. The point cloud data obtained by laser scanning is required in a region directly below the flight path of the UAV 200. Therefore, a high density laser scan is set on the ground surface vertically below the airspace where the UAV 200 is expected to fly. By doing so, the density of the scan data (point cloud data) is increased, and the scanning efficiency is increased.

An example of specific processing is shown below. First, the UAV future position prediction unit 118 predicts the position P ₁ of the UAV 200 at the future time t ₁ . Next, to obtain the coordinates directly below the vertical position P _1. For example, in the case of P ₁ (X ₁ , Y ₁ , Z ₁ ), P ′ (X ₁ , Y ₁ ) is the ground surface coordinates to be obtained. Next, a specific area including P ′ (X ₁ , Y ₁ ) is set as a scan range. For example, if a scan range having a specific length and width is set along the traveling direction of the UAV 200, a rectangular scan range having a length of 30 m and a width of 10 m including P ′ (X ₁ , Y ₁ ) is set. . This process is performed at future times t ₁ , t ₂ , t ₃ , t ₄ ... T _n and the scan range is set every moment.

  By setting the laser scan range as described above, the laser scan density is increased, and the probability that a point that coincides with or is as close as possible to the position vertically below the UAV 200 is increased. Therefore, the calculation accuracy of the ground altitude of the UAV 200 can be increased.

  The flight control signal generation unit 120 generates a control signal that causes the UAV 200 to fly at a predetermined ground altitude based on the ground altitude of the UAV 200 calculated by the UAV ground altitude calculation unit 117. This control signal is sent to the UAV 200, and flight control of the UAV 200 is performed.

Hereinafter, details of the processing performed by the flight control signal generation unit 120 will be described. For example, ground altitude is calculated at the time t is assumed to be Z _1. On the other hand, ground altitude in the relevant position in the flight plan is to be Z _0. In this case, if Z ₁ <Z ₀ , a control signal for raising the UAV is generated so that the ground altitude becomes Z ₀ , and it is sent to the UAV 200. If Z ₁ > Z ₀ , a control signal for lowering the UAV is generated so that the ground altitude becomes Z ₀ , and it is sent to the UAV 200.

  The following processing may be performed by the flight control signal generation unit 120. First, hovering is performed at an appropriate time when the flight is started, and the three-dimensional position of the UAV 200 at that time is acquired by the function of the TS 100. At this time, the three-dimensional position of the ground surface directly below the UAV 200 is acquired based on the point cloud data obtained by the laser scanner 112. Further, based on the flight plan, a laser scan of the ground surface along the planned flight path thereafter (laser scan of the ground surface vertically below the planned flight path) is performed to obtain point cloud data of the corresponding ground surface.

  Then, the altitude of the UAV 200 flying thereafter is controlled from the hovering point as a starting point in accordance with the change in altitude of the ground surface vertically below the flight path obtained by laser scanning. In this case, altitude control is performed on the basis of the altitude (the altitude obtained by laser scanning) at the point where the flight is scheduled. In other words, it is not a control that detects that the ground altitude deviates from the planned altitude and corrects the difference, but the altitude of the planned location is examined in advance by laser scanning, and the UAV 200 is configured so as to reach the planned ground altitude at that location. Flight control is performed. Of course, there is a case where it deviates from the planned altitude. In this case, the altitude is corrected based on the difference between the ground altitude obtained by the principle of FIG. 1 and the planned altitude.

(Example of processing)
Hereinafter, an example of processing performed in the TS 100 will be described. FIG. 3 is a flowchart illustrating an example of a processing procedure. The program for executing the processing of FIG. 3 is stored in an appropriate storage area such as the data storage unit 106, and is read out and executed from there. A mode in which the program is stored in an appropriate storage medium, a data server, or the like, read from the program, and executed is possible.

  In the following processing, the external orientation elements of TS100 are acquired in advance. When the process is started, tracking of the UAV 200 is first started (step S101). In this process, the reflection prism 202 is searched, and the tracking of the reflection prism 202 is started.

  The search for the reflection prism 202 is performed by the target search unit 102, and the tracking of the reflection prism 202 is performed by the UAV tracking control unit 111. Although not shown in FIG. 3, the position measuring unit 107 performs positioning of the reflecting prism 202 when the reflecting prism 202 as a target has been captured, and obtains data on the position of the UAV 200.

  Next, the scan range of the laser scanner 112 is set (step S102). In this process, the scan range is set based on the position of the UAV 200 obtained at this stage. This process is performed by the laser scan range setting unit 119. Laser scanning toward the ground surface is then started (step S103), and point cloud data on the ground surface by laser scanning is obtained (step S104).

  Next, positioning of the UAV 200 is performed (step S105). This process is performed by the position measurement unit 107. Next, the position (longitude, latitude, altitude) of the ground surface corresponding to the position of the UAV 200, that is, the three-dimensional position of the ground surface directly below the UAV 200 in the air is acquired based on the point cloud data obtained by laser scanning. (Step S106). This process is performed by the UAV corresponding ground position acquisition unit 116.

  Next, the ground height of the UAV 200 is calculated from the difference between the three-dimensional position of the UAV obtained in step S105 and the three-dimensional position of the ground surface corresponding to the position of the UAV 200 obtained in step S106 (step S107). This process is performed by the UAV ground altitude calculation unit 117.

  Then, it is determined whether or not the difference between the ground altitude calculated in step S108 and a predetermined altitude (planned ground altitude in the flight plan) is equal to or greater than a predetermined threshold (step S108). Here, when the difference in altitude is equal to or greater than the threshold, the flight control signal generation unit 120 generates a control signal for correcting the calculated altitude to a predetermined altitude. This control signal is sent to the UAV 200, and the flight altitude is corrected. If the difference in altitude is less than the threshold value, the processes in and after step S102 are repeated.

(Superiority)
Even if the altitude of the ground surface of the flight area is not accurately known, an accurate value of the ground altitude can be obtained using the laser scan data. Further, even if the measured ground altitude is deviated from a predetermined ground altitude, it can be corrected in a timely manner.

  For example, when the photogrammetry of the slope as shown in FIG. 4 is performed by the UAV, it is necessary to carry out the photogrammetry while flying along the slope while maintaining a specific ground altitude. At this time, if the present invention is used, the ground altitude of the flying UAV is always measured even if the accurate measurement data of the slope is not obtained, and the ground altitude of the UAV is appropriately corrected based on the result of this measurement. The

  At the construction site, the topography may change daily, and accurate elevation data may not be prepared in advance. Even in such a case, by using the present invention, the accurate ground altitude of the UAV can be obtained and the ground altitude can be controlled.

  Also, even if the topography changes at the disaster site and there is no accurate surface elevation data, you can grasp the ground altitude of the flying UAV and fly while controlling the UAV at a specific ground altitude. be able to.

2. Second Embodiment An example in which processing related to the ground altitude of the UAV is performed by an independent device is also possible. FIG. 5 shows a block diagram of the UAV ground altitude information processing apparatus 250. The UAV ground altitude information processing apparatus 250 includes a communication device 108, a control microcomputer 113, a UAV position data acquisition unit 114, a laser scan data acquisition unit 115, a UAV corresponding ground position acquisition unit 116, a UAV ground altitude calculation unit 117, and a UAV future position. A prediction unit 118, a laser scan range setting unit 119, and a flight control signal generation unit 120 are provided.

  The configuration of the same functional unit as that in FIG. 2 in the UAV ground altitude information processing apparatus 250 is the same as that described in relation to FIG. The control microcomputer 113 controls the processing performed by the UAV ground altitude information processing apparatus 250 in an integrated manner.

  The UAV ground altitude information processing apparatus 250 is hardware that operates as a computer including a CPU and other arithmetic circuits, and may be configured using a general-purpose computer, or dedicated hardware using an FPGA or the like. (Electronic circuit) may be used.

  The UAV ground altitude information processing apparatus 250 performs processing related to the ground altitude described in the first embodiment, calculates the ground altitude of the UAV 200, and controls the UAV ground altitude. The UAV ground altitude information processing apparatus 250 is used in cooperation with a general-purpose TS. In this case, tracking and positioning of the UAV 200 are performed using a general-purpose TS. In addition, communication is performed between the TS and the UAV using the communication unit 122.

  Specifically, the UAV ground altitude information processing apparatus 250 acquires UAV position data and laser scan data from a general-purpose TS, and further instructs the TS to specify a scan range. Also, the ground altitude is controlled for the UAV.

3. Third Embodiment FIG. 6 shows another example system using the present invention. In this example, TS is not used, and an independent laser scanner 500 is used. In this example, the UAV ground altitude information processing apparatus 400 is used.

  FIG. 7 shows a block diagram of the UAV ground altitude information processing apparatus 400. The UAV ground altitude information processing apparatus 400 includes a communication device 108, a control microcomputer 113, a UAV position data acquisition unit 114, a laser scan data acquisition unit 115, a UAV corresponding ground position acquisition unit 116, a UAV ground altitude calculation unit 117, and a UAV future position. A prediction unit 118, a laser scan range setting unit 119, a flight control signal generation unit 120, and a UAV positioning unit 121 are provided.

  In the UAV ground altitude information processing apparatus 400, the same functional configuration as that in FIG. 2 is the same as that described in relation to FIG. The control microcomputer 113 controls the processing performed by the UAV ground altitude information processing apparatus 250 in an integrated manner.

  The UAV ground altitude information processing apparatus 400 is hardware that operates as a computer, and may be configured by using a general-purpose computer, or may be configured by dedicated hardware (electronic circuit) using FPGA or the like. Good.

  In this example, the UAV 200 and the UAV ground altitude information processing apparatus 400 can communicate with each other. For the communication, a known wireless communication standard such as a wireless LAN standard is used. The UAV 200 includes a GNSS device, and the UAV 200 position data (longitude, latitude, altitude) measured there is acquired by the UAV position data acquisition unit 114.

  The UAV positioning unit 121 performs positioning of the UAV 200 by relative positioning. This process is performed as follows. In this example, the laser scanner 500 is installed at a known position, and its external orientation element is acquired in advance. Moreover, the installation position is continuously measured using the high precision GNSS apparatus which is not shown in figure. On the other hand, the UAV 200 sends its positioning data to the UAV positioning unit 121 via the communication device 108. The UAV positioning unit 121 performs relative positioning of the UAV 200 using the positioning data of the high-accuracy GNSS device and the positioning data transmitted from the UAV 200.

  The UAV ground altitude information processing apparatus 400 receives positioning data from the UAV 200 and positioning data from the laser scanner 500. Then, relative positioning of the UAV 200 based on the two positioning data is performed by the UAV positioning unit 121. The relative positioning data related to the UAV 200 is acquired by the UAV position data acquisition unit 114. Note that the processing related to laser scanning is the same as in the first embodiment.

4). Others Multiple TSs can be used. TS and laser scanner can also be used separately. In this case, the position of TS and the laser scanner may be separated. However, the external orientation elements of TS and laser scanner are acquired in advance.

  When the UAV is operated by remote control, it is possible to constantly monitor the UAV's ground altitude by using the present invention and notify the operator of the result. In addition, it is possible to notify the operator of a deviation from a specified ground altitude. The subject of the present invention is mainly unmanned aircraft, but may be manned aircraft.

  As the ground altitude, the distance between the ground surface and a UAV (aircraft) in a direction perpendicular to the ground surface can be adopted. For example, in the case of photogrammetry on an inclined surface, there may be a case where the distance between the ground surface and the UAV in a direction perpendicular to the inclined surface is a problem. In this case, the distance between the ground surface and the UAV on the direction line viewed in the direction perpendicular to the ground surface is adopted as the ground altitude.

  In this case, in the laser scan data of the ground surface, the ground surface is divided into a large number of local regions composed of 9 points × 9 points, 15 points × 15 points, and the like. Then, a plane to be fitted to each local region is obtained, and a perpendicular to this plane is obtained. Then, a local area where the UAV is located on this perpendicular is searched, and the distance between the local area and the UAV in the direction perpendicular to the local area is obtained as the ground altitude.

  When the flatness of the ground surface is good, the local region may be a wide range. If the ground surface is a horizontal plane, the ground altitude in this case coincides with the ground altitude in the first embodiment.

  As the laser scanner 112 or 500, an electronic laser scanner that performs electronic scanning can also be used. In the electronic laser scanner, the direction of the distance measuring light is controlled not by a mechanical mirror but by an electronic method (solid state optical phased array method). This technique is described in, for example, US Publication No. US2015 / 0293224.

  100 ... TS (total station), 200 ... UAV, 201 ... camera, 200 ... reflecting prism.

Claims (7)

Aircraft position acquisition unit that acquires three-dimensional position P ₁ of the aircraft flying,
A ground surface position acquisition unit that acquires data of a ground surface position P ₂ corresponding to the position of the flying aircraft based on laser scan data for the ground surface corresponding to the P ₁ ;
The information processing apparatus according to the unmanned aircraft and a ground height calculation unit for calculating the ground height of the aircraft based on the difference of the P ₁ and the P _2. A future position prediction unit that predicts a future position of the aircraft based on a flight plan of the aircraft and / or a flight trajectory of the aircraft;
The information processing apparatus according to claim 1, further comprising: a scan range setting unit configured to set a scan range for acquiring the laser scan data based on the future position.   3. The control signal generation unit according to claim 1, further comprising a control signal generation unit configured to generate a control signal for performing flight control for reducing a difference between the ground altitude calculated by the ground altitude calculation unit and a predetermined ground altitude. Information processing device. The terrestrial position acquisition unit, the information processing apparatus according to claim 1 to perform the ground altitude is calculated based on the coordinates of a plurality of points surrounding the position of the P ₂ in the laser scan data. The position of the P ₁ is the position of the flight schedule,
The information processing apparatus according to any one of claims 1 to 4, wherein the ground altitude is a value at the planned flight position. Aircraft position acquisition step of acquiring a three-dimensional position P ₁ of the aircraft flying,
And surface position acquisition step of acquiring data of surface positions P ₂ that based on laser scan data, corresponding to the position of the aircraft to the flight against the ground corresponding to the P _1,
The information processing method according to the unmanned aircraft and a ground height calculation step of calculating the P ₁ and the P of the aircraft based on a difference ₂ AGL. A program that is read and executed by a computer,
Aircraft position acquisition unit that acquires three-dimensional position P ₁ of the aircraft flying computer,
A ground surface position acquisition unit that acquires data of a ground surface position P ₂ corresponding to the position of the flying aircraft based on laser scan data for the ground surface corresponding to the P ₁ ;
The information processing program to function as a ground height calculation unit for calculating the ground height of the aircraft based on the difference of the P ₁ and the P _2.

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