JP7362203B2 - unmanned moving body - Google Patents

Description

TECHNICAL FIELD The present invention relates to a remotely controlled or autonomous unmanned mobile object, and particularly to a drone equipped with a function of photographing an object.

For example, inspection of the surface of power transmission lines installed on a steel tower can be carried out by a worker using binoculars to directly observe the surface of the power line, by a helicopter, or by a person climbing the tower and inspecting the surface of the power line as it travels along the line. This is done by using self-propelled aircraft. If it were possible to inspect such high-altitude structures by bringing a drone equipped with an aerial photography function close and photographing the inspection area with a camera, it would be possible to obtain images similar to those seen by workers visually inspecting the inspection area. This makes it possible to significantly reduce the costs required. Furthermore, autonomous control technology is being developed and put into practical use to control the aircraft so that it flies along a predetermined flight route at a predetermined speed, automatically returns to the takeoff point, and then lands.

In the aerial photography method disclosed in Patent Document 1, as shown in FIG. Fly to point (a) above, then fly parallel to point (b) above steel tower B along the elevated power line W, during which time the elevated power line W is located at the center of the camera's imaging area. While tracking the elevated power line W, images of the elevated power line W are continuously recorded. In addition, by measuring the distance to the elevated wire W during flight and adjusting the zoom magnification of the camera according to the measured distance, the high-definition elevated wire W can be enlarged to a sufficient size within the camera frame. It is possible to record video. Furthermore, in Patent Document 2, a multispectral camera mounted on an unmanned aircraft is used to monitor the growth status of plants, and if image data is determined to be abnormal due to missing data, etc., the image is re-photographed.

JP2006-027448A Japanese Patent Application Publication No. 2018-152737

In recent years, there has been development and practical use of systems for inspecting overhead ground wires and power lines using small unmanned aircraft such as drones, and surveying systems that obtain detailed shapes of terrain by continuously photographing the terrain over a certain area. It is progressing. The drone is equipped with an object detection sensor (for example, LiDAR) that detects the distance and angle to the object to be inspected, and the drone maintains a constant positional relationship between the aircraft and the object to be inspected based on the detection results of the object detection sensor. By flying autonomously in such a way that the robot is able to track the object to be inspected, contact with the object is prevented. Additionally, the drone is equipped with a camera via a gimbal that captures images of the inspection target. A gimbal is an actuator that can finely adjust the orientation of a camera in three dimensions, and a gimbal is an actuator that allows the object detection sensor to detect objects so that the camera always captures images in the vertical direction of the drone even if the drone's attitude changes. Use the results to control the camera angle. As a result, imaging is controlled so that the inspection target is imaged at the center of the imaging frame.

When performing inspection photography using a drone, the attitude and position of the aircraft may change suddenly due to factors such as strong winds. At this time, the gimbal operates to absorb changes in the attitude of the aircraft. FIG. 2(A) is a diagram schematically showing the aircraft 10 and the elevated electric wire W from the side. When a wind K blows from the side while flying directly above the elevated electrical wire W, the aircraft 10 moves toward the wind. The aircraft tilts and attempts to maintain a flight position directly above the overhead power lines W. At this time, the gimbal controls the angle of the camera so that the overhead wire W enters the imaging range S.

FIG. 2(B) is a diagram schematically showing the aircraft body 10 and the elevated electric wire W from above, and shows that when wind K blows, the airframe 10 moves in the lateral direction P away from the elevated electric wire W. There are cases where this happens. In this case as well, the flight of the aircraft 10 is controlled so as to head in the direction Q of the overhead wire W, and the gimbal also controls the angle of the camera so as to suppress these influences. However, if the rapid attitude change of the drone cannot be absorbed in the end, as shown in FIG. 3, a frame-out occurs in which the overhead electric wire W deviates from the photographing range S, and photographing may fail.

FIG. 4 is a diagram schematically showing a survey flight. The aircraft 10 surveys the terrain based on the control point 20 according to a flight route R prepared in advance. However, if there are trees, steel towers, tall buildings, birds, etc. on the flight route, the focus may temporarily change. This may result in failure in photographing the verification point 22.

The above-mentioned failures in shooting due to frame outs and focus shifts were determined by playing back and checking the footage shot by the camera after the drone returned. For this reason, the re-photographing process required the same flight to be performed again, which was time-consuming. In addition, additional batteries may be required for the drone for re-flight, which could create a situation where it is difficult to manage on-site.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to provide an unmanned moving object that can easily re-photograph an object when photographing it fails.

The unmanned moving object according to the present invention includes a position detection means for detecting the position of the moving object, a photographing means for photographing the object, and a movement for moving the mobile object according to a movement route prepared in advance for photographing the object. a detection means for detecting a failure in photographing an object by the photographing means; and a detection means for detecting a failure in photographing an object by the photographing means; It has a control means for controlling the moving means and the photographing means so as to perform re-photographing.

In one embodiment, the detection means detects a failure in photographing based on whether the object is included in the photographing range of the photographing means. In one embodiment, the detection means detects a failure in photographing based on whether the object photographed by the photographing means is in focus. In one embodiment, the detection means detects a failure in photographing in units of video frames photographed by the photographing means, and the control means re-photographs the object at the position where the photographing has failed, and then controls the previously prepared The moving means and the photographing means are controlled so as to return to the travel route taken. In one embodiment, the flight means controls the moving means and the photographing means so as to re-photograph the object at the position where the photographing failed after reaching the photographing end point of the travel route. In one embodiment, the unmanned mobile object further includes communication means for communicating data with a base station, and the detection means detects a failure in photographing based on information transmitted from the base station via the communication means, The control means controls the moving means and the photographing means based on information transmitted from the base station.

According to the present invention, when a photographing failure of an object is detected, the photographing is re-photographed from the position where the photographing failure was detected. Therefore, when photographing fails, there is no need to perform the same flight for re-photographing. In addition, the energy and flight time of the unmanned moving vehicle consumed for re-shooting can be reduced.

FIG. 2 is a diagram illustrating an example of a conventional unmanned aircraft that takes aerial photographs of elevated power lines and the like. FIG. 2(A) is a diagram schematically showing the fuselage and the overhead power cables from the side, and FIG. 2(B) is a diagram schematically showing the fuselage and the overhead power cables from above. It explains how the attitude of the aircraft changes due to etc. FIG. 2 is a diagram illustrating an example in which an object to be inspected deviates from the frame in aerial photography using a conventional unmanned aircraft. FIG. 2 is a diagram schematically showing photographing for surveying using a conventional unmanned aircraft. FIG. 1 is a block diagram showing the electrical configuration of an unmanned aircraft according to the present invention. FIG. 2 is a block diagram showing a functional configuration of a photographing control program according to an embodiment of the present invention. 7(A) and 7(B) show the relationship between the video frame and the elevated electric wire, and FIGS. 7(C) and 7(D) are diagrams illustrating an example of failure in imaging. FIG. 3 is a diagram illustrating a method for determining whether or not a frame-out occurs according to an embodiment of the present invention. FIG. 3 is a diagram showing an operation flow of first photographing control of a target according to an embodiment of the present invention. FIG. 7 is a diagram illustrating re-imaging in the first imaging control when imaging fails according to the embodiment of the present invention. FIG. 7 is a diagram showing an operation flow of second photographing control of a target according to an embodiment of the present invention. FIG. 7 is a diagram illustrating re-imaging in the second imaging control when imaging fails according to the embodiment of the present invention.

Next, embodiments of the present invention will be described. The unmanned mobile object of the present invention is, for example, a drone, an unmanned aircraft such as a helicopter airship, or a drone (rover) that moves on wheels. The unmanned mobile object of the present invention is used for inspecting natural disaster sites such as power transmission lines installed on steel towers and landslides, which are difficult for humans to visually inspect, or for surveying topography.

In the following embodiments, an example will be described in which an unmanned aircraft (drone) is used as an unmanned moving object to photograph an object to be inspected or to survey the terrain. The unmanned aircraft (drone) of this embodiment is equipped with a photographing camera for photographing objects to be inspected (e.g., elevated power lines) and terrain on the main body. The photographing camera is attached to the main body of the aircraft via an angle adjustment actuator such as a gimbal. The angle adjustment actuator is capable of adjusting the angle of the photographing camera, for example, with three degrees of freedom in the X-axis, Y-axis, and Z-axis. For example, the unmanned aircraft photographs an electric wire W elevated on a steel tower in the vertical direction as shown in FIG. 1, or photographs the topography as shown in FIG. 4. The photographed video data is used for inspecting the elevated power lines W and surveying the topography.

FIG. 5 is a block diagram showing the electrical configuration of the unmanned aircraft according to this embodiment. The unmanned aircraft 100 according to this embodiment includes a GPS receiving section 110, an independent navigation sensor 120, an object detecting section 130, a photographing camera 140, a camera angle adjusting section 150, a rotor driving section 160, a storage section 170, an output section 180, and a communication section. 190 and a control section 200. However, the above configuration is an example and is not necessarily limited to this.

The GPS receiving unit 110 receives GPS signals emitted from GPS satellites, and detects the absolute position of the unmanned aircraft 100 including latitude and longitude. The unmanned aircraft 100 is capable of autonomous navigation according to flight information prepared in advance. For example, as shown in FIG. 1, the flight information includes a flight route (flying from ground station 2 as a departure point, point (a) of tower A, point (b) of tower B, and ground station 2 as a return point). (including location information such as latitude and longitude), flight speed, flight altitude, etc. The unmanned aircraft 100 flies while following a flight route using the position information detected by the GPS receiving unit 110.

The autonomous navigation sensor 120 includes sensors necessary for the unmanned aircraft 100 to autonomously navigate, such as a direction sensor and an altitude sensor. The sensor output of the autonomous navigation sensor 120 is used for control when autonomously flying according to flight information.

The object detection unit 130 detects the relative distance and angle to the inspection target. The object detection unit 130 is configured using, for example, LiDAR (Laser Imaging Detection and Ranging). LiDAR detects the distance and angle to an object by emitting pulsed laser light in 360-degree directions and measuring the reflected light from the laser irradiation. The object detection unit 130 detects, for example, the distance and angle to the elevated electric wire W, which is the object to be inspected, or the distance and angle to the verification point 22 (see FIG. 4), which is the object to be surveyed. Note that the object detection unit 130 is not limited to LiDAR, and may detect the distance and angle to the object using a plurality of stereo cameras. Based on the detection result of the object detection unit 130, the unmanned aircraft 100 tracks the elevated electric wire W so as to maintain a constant distance and angle from the elevated electric wire W that is the object to be inspected, or to keep a constant distance and angle from the elevated electric wire W that is the object to be measured. The verification point is tracked so as to maintain the distance and angle of .

As described above, the photographing camera 140 is attached to the lower part of the aircraft body via the angle adjustment actuator. The photographing camera 140 takes a moving image of the elevated electric wire W, which is the object to be inspected, and the verification point 22, which is the object to be measured, and generates, for example, 24 video frames (still images) per second. Further, the photographing camera 140 has a zoom function, and its magnification is adjusted so that the elevated electric wire W and the verification point 22 of a certain size are captured in the video frame.

The camera angle adjustment section 150 drives an angle adjustment actuator in response to an angle adjustment signal from the control section 200, and adjusts the angle of the photographing camera 140. The control unit 200 calculates the angle at which the imaging direction of the imaging camera 140 (optical axis of the lens of the imaging camera) is vertical based on the detection results of the independent navigation sensor 120 and the object detection unit 130, and calculates the angle based on the calculation result. Generate an adjustment signal.

The rotor drive unit 160 rotates a rotor connected to a propeller or the like based on a drive signal from the control unit 200. The control unit 200 generates a drive signal for the unmanned aircraft 100 to autonomously fly along a flight route based on the information and flight information detected by the GPS reception unit 110, the autonomous navigation sensor 120, and the object detection unit 130.

Storage unit 170 stores various information necessary for operating unmanned aircraft 100. For example, the storage unit 170 stores flight information prepared in advance, stores programs and software to be executed by the control unit 200, and stores information on objects to be inspected or measured that are imaged by the camera 140. Store video data. Furthermore, in this embodiment, the storage unit 170 stores photographing failure information indicating that the photographing camera 140 has failed in photographing the object. The photographing failure information can notify the user that the object needs to be photographed again without reproducing the video data photographed by the photographing camera 140.

The output unit 180 reads information stored in the storage unit 170 and outputs it to the outside. Although the configuration of the output unit 180 is not particularly limited, for example, the output unit 180 may include a display unit that displays video data in the storage unit 170, or may be provided with an external base station connected via the communication unit 190. , information read from the storage unit 170 can be output by wire or wirelessly.

The communication unit 190 enables the unmanned aircraft 100 to perform data communication with an external base station by wire or wirelessly. An external base station (for example, a computer device) can control the unmanned aircraft 100 via the communication unit 190, and can, for example, set flight information in the storage unit 170 of the unmanned aircraft 100, or It is possible to receive video data photographed by the user, or to give instructions from the user to the control unit 200.

The control unit 200 controls each part of the unmanned aircraft 100. In one embodiment, the control unit 200 includes a microcontroller including a ROM/RAM, a microprocessor, an image processing processor, etc., and controls the unmanned aircraft by executing programs and software stored in the storage unit 170 or the ROM/RAM. Controls 100 autonomous flights and photography of inspection objects.

The autonomous flight control program allows the unmanned aircraft 100 to follow a pre-prepared flight route based on the absolute position (latitude, longitude, altitude) detected by the GPS receiver 110 and the direction and altitude detected by the autonomous navigation sensor 120. Control it to fly. This flight route is a route along the elevated electric wire W which is the part to be inspected and the verification point 22 which is the object to be measured. Further, the autonomous flight control program executes the automatic flight control program to maintain a certain distance from the elevated electrical wire W and the verification point 22 based on the relative distance and angle between the elevated electrical wire W and the verification point 22 detected by the object detection unit 130. The flight of the unmanned aircraft 100 is controlled so as to track the verification point 22.

While the unmanned aircraft 100 continues to fly along the target object, the photographing control program controls the photographing camera 140 so that the elevated electric wire W and the verification point 22 are photographed, and also controls the video data photographed by the photographing camera 140. The information is stored in the storage unit 170. FIG. 6 shows the detailed configuration of the imaging control program of this embodiment. As shown in the figure, the photographing control program 210 includes a camera angle calculation section 220, a camera operation control section 230, a photographing failure detection section 240, a re-photographing control section 250, and a video data storage section 260.

The camera angle calculating section 220 calculates the angle of the photographing direction of the photographing camera 140 based on the detection result from the object detecting section 130 so that the elevated electric wire W and the verification point 22 can be captured in the video frame of the photographing camera 140. do. When the camera angle calculation unit 220 calculates the angle of the shooting direction, it provides an angle adjustment signal representing the calculation result to the camera angle adjustment unit 150, and the camera angle adjustment unit 150 drives the angle adjustment actuator based on the angle adjustment signal. Then, the shooting direction of the imaging camera 140 is adjusted. In this embodiment, the camera angle calculation unit 220 calculates the angle so that the imaging direction (optical axis) of the imaging camera 140 is in the vertical direction. Take an aerial shot from directly above.

Further, the zoom of the photographing camera 140 is set to a predetermined magnification, and the flight is controlled by the autonomous flight control program so that the relative distance between the unmanned aircraft 100 and the elevated electric wire W and the verification point 22 is constant. . These settings determine the range of the real space (the distance in the real space in the vertical and horizontal directions) captured by the video frame of the camera 140, that is, the size of the elevated electric wire W shown in the video frame is determined. It is determined. For example, as shown in FIG. 7A, an elevated electric wire W is displayed in a video frame F in a size that can be inspected by the user.

In FIG. 7A, when the longitudinal direction of the video frame F is approximately parallel to the flight direction, the camera angle calculation unit 220 calculates the video frame F based on the relative angle of the elevated electric wire W detected by the object detection unit 130. The angle of the camera is calculated so that the elevated electric wire W can be captured approximately in the center of the area. In addition, as shown in FIG. 7(B), the unmanned aircraft 100 may be affected by the wind, causing the attitude of the aircraft to change as shown in FIG. 2(A), or as shown in FIG. 2(B). When moving away from the electric wire W, the elevated electric wire W shown in the video frame F shifts from the center to the edge. In this case, the camera angle calculation unit 220 calculates the relative Based on the amount of change in angle, the camera angle is calculated so that the elevated electric wire W moves in the central direction Q. The same applies when photographing the verification point 22, which is the object to be measured.

The camera operation control unit 230 controls the start and end of shooting, etc. of the shooting camera 140. Specifically, when the unmanned aircraft 100 starts flying along the flight route, approaches the elevated electric wire W and the verification point 22, and reaches the shooting start position, the camera operation control unit 230 starts the shooting camera 140 to start shooting. When the unmanned aircraft 100 reaches the photographing end position along the flight route, the photographing camera 140 finishes photographing. In addition to the above, the camera operation control unit 230 can also control the imaging conditions of the imaging camera, such as magnification.

The photographing failure detection unit 240 detects a failure in photographing by the photographing camera 140 during a period in which the photographing camera 140 is photographing the elevated electric wire W or the verification point 22 . When the attitude of the unmanned aircraft 100 suddenly changes due to the influence of strong winds (see Figure 2 (A)) or temporarily deviates from the flight route (see Figure 2 (B)) during photography. ), if the angle control of the photographing camera 140 by the angle adjustment actuator is not done in time, the overhead electric wire W may come out of the video frame F, as shown in FIG. 7(C). The photographing failure detection unit 240 regards such frame-out as a photographing failure and detects it. The presence or absence of frame-out is determined from the relative positions of the elevated electric wire W and the verification point 22 detected by the object detection unit 130, the currently controlled angle of the angle adjustment actuator, and the viewing angle set on the photographing camera. be able to.

FIG. 8 is a diagram illustrating a method for determining the presence or absence of frame-out. It is assumed that the flight direction of the unmanned aircraft 100 is approximately parallel to the direction in which the elevated electric wire W extends. In this state, the relative angle θw of the elevated electric wire W with respect to the vertical reference line G of the unmanned aircraft 100 is detected by the object detection unit 130. Further, the angle of view θc of the photographing camera 140 is a known value determined from the zoom magnification, and the angle of view θc defines the size of the video frame F shown in FIG. When the current angle of the angle adjustment actuator with respect to the reference line G is θa (the angle θa is equal to the optical axis direction of the photographing lens of the photographing camera 140), the angle of view θc is the direction of the angle offset by the angle θa. Take a photo. The imaging determination unit 240 determines whether the angle θw of the elevated electric wire W is included in the imaging range of the angle of view θc offset by θa, and if the difference between the two is a certain value or more, is not photographed, that is, it is determined that the elevated electric wire W has gone out of the video frame F.

Further, when the elevated electric wire W is photographed at the outer edge of the video frame F, there is a possibility that a part of the elevated electric wire W may be missing or the image may become unclear due to optical distortion. For this reason, as shown in FIG. 7(D), a certain margin M may be provided around the outer periphery of the video frame F, and it may be determined whether or not the elevated electric wire W is photographed inside the margin M. In this case, an angle of view θc' (θc'<θc) that defines the margin M is set. Note that determination as to whether or not there is a flameout at the verification point 22, which is the object to be measured, is performed in the same manner.

Furthermore, since the camera 140 generates a plurality of video frames per second (for example, 24 video frames per second), if the overhead wire W goes out of frame in a very short time, , it is possible to interpolate the elevated electric wire W during the frame-out period using the previous and subsequent video frames. Therefore, the imaging failure detection unit 240 determines that imaging has failed when frame-out occurs for a certain period of time. For example, when 24 video frames are generated per second, it is determined that the photographing of the elevated electric wire W has failed if frame-out occurs in 12 video frames.

In addition to determining the presence or absence of a frame-out, the photographing failure detection unit 240 may consider that when a focus shift (out of focus) of a photographed object occurs, this is regarded as a photographing failure. For example, as shown in FIG. 4, if there are tall buildings such as trees or steel towers on the flight route R, the verification point 22 will not be in focus, and the focus will be on the trees, steel towers, etc. temporarily. The presence or absence of a focus shift can be determined, for example, from the power spectrum of captured video data. When an object is out of focus, the outline of the object becomes unclear, the amount of change in image data between adjacent pixels forming the outline becomes small, and its frequency becomes low. On the other hand, if the image is in focus, the amount of change in image data between pixels will increase, and the frequency will increase. The imaging failure detection unit 240 analyzes captured video data, monitors out-of-focus from its power spectrum, and detects out-of-focus periods.

When the photographing failure detection unit 240 detects a photographing failure, the photographing failure detection unit 240 generates photographing failure position information indicating in which position or section of the flight route the photographing failed based on the position information of the unmanned aircraft 100 detected by the GPS receiving unit 110. and provides it to the re-imaging control unit 250.

When the reshooting control unit 250 receives the shooting failure position information from the shooting failure detection unit 240, it controls the autonomous flight control program and the camera operation control unit 230 based on the shooting failure position information, and moves the unmanned aircraft 100 to the position where the shooting failure occurred. The object will then be photographed again.

The video data storage section 260 stores, in the storage section 170, video data photographed during the period in which the photographing camera 140 is in operation and video data re-photographed by the re-photography control section 250.

Next, the first photographing operation by the unmanned aircraft 100 of this embodiment will be explained with reference to the flow shown in FIG. Here, it is assumed that the elevated electric wire W is photographed. First, a computer device is connected via the communication unit 190, and flight information including a flight route is input from the computer device to the unmanned aircraft 100 (S100), and this is stored in the storage unit 170 or the RAM of the control unit 200. The autonomous flight control program of the control unit 200 starts autonomous flight of the unmanned aircraft according to the input flight information (S110).

The unmanned aircraft 100 autonomously flies along the elevated electrical wire W while maintaining a certain distance from the elevated electrical wire W based on the relative distance and angle to the elevated electrical wire W detected by the object detection unit 130. will be photographed. That is, when the unmanned aircraft 100 reaches the photographing start position of the elevated electric wire W, the camera operation control unit 230 activates the photographing camera 140 and starts photographing the elevated electric wire W (S120).

During the shooting period, the camera angle calculation unit 220 calculates the angle of the shooting direction of the shooting camera 140 based on the distance and angle to the elevated electric wire W detected by the object detection unit 130, and adjusts the angle adjustment signal to the angle based on the calculation result. The signal is output to the adjustment actuator, and the angle adjustment actuator adjusts the angle of the photographing camera 140. Further, during the photographing period, the video data of the elevated electric wire W photographed by the photographing camera 140 is sequentially stored in the storage section 170 by the video data storage section 260. Further, during the photographing, the photographing failure detection unit 240 detects whether there is a photographing failure of the elevated electric wire W (S130), and if a photographing failure is detected, the photographing failure position information is provided to the re-photographing control unit 250. , the re-imaging control unit 250 holds the provided imaging failure position information (S140).

When the unmanned aircraft 100 reaches the photographing end point of the elevated electric wire W based on the flight route (S150), the camera operation control unit 230 stops photographing the elevated electric wire (S160), and the re-photographing control unit 250 updates the photographing failure position information. is held (S170), and if the shooting failure position information is held, the autonomous flight control program is controlled so that the unmanned aircraft 100 flies to the shooting failure position, and the camera operation control unit 230, the photographing camera 140 is activated and the elevated electric wire W is photographed again (S180). The re-photographed video data of the elevated electric wire W is stored in the storage unit 170. If there is multiple photographing failure position information, the unmanned aircraft 100 is similarly flown to the photographing failure position for all of them, and the elevated electric wire W is re-photographed there. When the re-photographing is completed, the camera operation control unit 230 stops the photographing camera 140, and the unmanned aircraft 100 returns to the starting point (S190). On the other hand, if the photographing failure position information is not held in the re-photographing control unit 250, the unmanned aircraft 100 is returned to the starting point without performing re-photographing (S190).

FIG. 10 shows an example of a flight of an unmanned aircraft when re-photographing the elevated electric wire W. As shown in FIG. 10(A), the unmanned aircraft 100 photographs continuous elevated electric wires W along a flight route R, and during the photographing, the photographing failure detection unit 240 detects a photographing failure in a photographing range S at a photographing point Z. When detected, photographing failure position information including the photographing point Z is generated, and this is held in the re-photographing control unit 250. The unmanned aircraft 100 continues photographing the elevated electric wire W along the flight route R until the photographing end point E. When the unmanned aircraft 100 reaches the shooting end point E, the reshooting control unit 250 generates a flight route R1 based on the shooting failure position information, and flies the unmanned aircraft 100 along this flight route R1 to the shooting failure point Z. Then, the elevated electric wire W is photographed again.

In this way, according to this embodiment, if the object fails to be photographed, the object is automatically re-photographed at the point where the photographing failed, so that it is possible to improve the efficiency of photographing the object. can.

Next, the second photographing operation by the unmanned aircraft 100 of this embodiment will be explained with reference to the flow shown in FIG. 11. Here, it is assumed that a discontinuous measurement object such as a verification point is photographed. Steps S100 to S130 are the same as those in FIG. 9, so their explanation will be omitted. When the photographing failure detection unit 240 detects a photographing failure (S130), the re-photographing control unit 250 returns the unmanned aircraft 100 to the point where the photographing failed based on the photographing failure position information (S200), and there, the measurement target ( For example, the verification point 22) is photographed again (S210). When the re-photographing is completed by the re-photographing control unit 250, the object to be measured is photographed again along the flight route. When the unmanned aircraft 100 reaches the end point for photographing the object to be measured based on the flight route (S220), the camera operation control unit 230 stops photographing the object to be measured (S230), and the unmanned airplane 100 returns to the starting point. (S240).

FIG. 12 shows an example of the flight of the unmanned aircraft when retaking the image shown in FIG. 11. The unmanned aircraft 100 sequentially photographs video frames Fn-1, Fn, Fn+1, etc., as shown in FIG. 12(A). If the shooting failure detection unit 240 detects a shooting failure of the video frame Fn, the shooting failure position information including the position information detected by the GPS receiving unit 110 when the video frame Fn was shot is provided to the reshooting control unit 250. be done. The reshooting control unit 250 returns the unmanned aircraft 100 to the position where the shooting failed based on the shooting failure position information, as shown in FIG. 12(B), and reshoots the video frame Fn there. Note that if a shooting failure is detected in a plurality of consecutive video frames, reshooting of the plurality of consecutive video frames is performed.

As described above, according to this embodiment, when photographing a target object fails, it is possible to return to the original position where the photographing failed, retake the photograph there, and then perform normal photographing. It is possible to improve the efficiency of photographing. In particular, the photographing method of this example is suitable when performing processing to extract a difference or parallax of an object between video frames.

Next, a second embodiment of the present invention will be described. In the above embodiment, an example was shown in which the photographing control program of the unmanned aircraft 100 detects a photographing failure and controls subsequent re-photographing, but in the second embodiment, a base station on the ground detects a photographing failure, Control reshoots.

The unmanned aircraft 100 tracks an object along the flight route, and when the object (elevated electric wire W, verification point, etc.) is photographed by the photographing camera 140, the communication unit 190 transmits the photographed video data to the base station. do. Current position information of the unmanned aircraft detected by the GPS receiving unit 190 is added to the video data to be transmitted. The base station analyzes the received video data and detects whether there is a shooting failure. When the base station detects a photographing failure, it generates flight information for re-photographing and transmits this to the unmanned aircraft 100. The communication unit 190 provides the received flight information for re-shooting to the control unit 200, the autonomous flight control program causes the unmanned aircraft 100 to fly based on the flight information for re-shooting, and the camera operation control unit 230 , re-photograph the object at the location where the photographing failed.

As described above, according to the present embodiment, the processing load on the unmanned aircraft 100 can be reduced by detecting an imaging failure and controlling re-imaging on the base station side on the ground.

In the above embodiment, for ease of explanation, an example was shown in which the shooting direction of the shooting camera 140 is adjusted in the lateral direction of the video frame F, as shown in FIG. If the flight direction is misaligned with the direction of the elevated electric wire W, the shooting direction of the imaging camera 140 may also be adjusted in the longitudinal direction of the video frame. In other words, the angle adjustment actuator can adjust the angle of the camera with two degrees of freedom in the lateral and longitudinal directions of the video frame F.

Further, in the above embodiment, an example was shown in which images of elevated electric wires and topography were taken, but this is just an example, and the present invention can also be applied to taking photos of other high-rise buildings, natural disaster areas, etc. Furthermore, this embodiment has shown an example in which the photographing camera is attached to the aircraft body via the angle adjustment actuator, but if the photographing camera itself is equipped with an electronic or optical angle adjustment function for the photographing direction, An angle adjustment actuator is not necessarily required.

Further, in the above embodiments, an example is given of photographing an object using an unmanned aircraft, but the present invention is not limited to this, and can also be applied to a drone (rover) that moves on wheels.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to specific embodiments, and various modifications and variations can be made within the scope of the gist of the invention described in the claims. Changes are possible.

100: Unmanned aircraft 110: GPS receiving unit 120: Independent navigation sensor 130: Object detection unit 140: Photographing camera 150: Camera angle adjustment unit 160: Rotor drive unit 170: Storage unit 180: Output unit 190: Communication unit 190
200: Control unit

Claims (6)

a position detection means for detecting the position of the moving body;
a photographing means including a photographing camera for photographing the object;
object detection means for detecting the relative position of the object;
An angle adjusting means for adjusting the angle of the photographing direction of the photographing camera based on the detection by the object detecting means;
a moving means for moving a moving object according to a moving route prepared in advance to photograph a target object;
Detection means for detecting a failure in photographing an object by the photographing means;
control means for controlling the moving means and the photographing means so that when the detection means detects a failure in photographing, the object is re-photographed at the position detected by the position detection means at which the photographing has failed; death,
The detection means determines whether or not the object is included in the photographing range of the photographing means, based on the relative position of the object detected by the object detection means and the angle of the photographing direction adjusted by the angle adjustment means. An unmanned moving object that detects failures in shooting . The detection means determines whether the object is included in the photographing range of the photographing means based on the relative angle of the object, the angle of the photographing direction adjusted by the angle adjusting means, and the angle of view of the photographing camera . The unmanned moving object according to claim 1, which detects failure in photographing. The unmanned vehicle according to claim 1, wherein the detection means detects a failure in photographing based on whether the object is included within a certain margin set on the outer periphery of the video frame photographed by the photographing means. mobile object. The detection means detects failure in photographing in units of video frames photographed by the photographing means, and the control means re-photographs the object at the position where the photographing has failed, and then moves the object along the pre-prepared movement route. The unmanned moving object according to claim 1, wherein the moving means and the photographing means are controlled so as to return. The unmanned movement according to claim 1, wherein the control means controls the moving means and the photographing means so as to re-photograph the object at the position where the photographing failed after reaching the photographing end point of the moving route. body. The unmanned mobile object further includes communication means for communicating data with the base station,
The communication means transmits the video data photographed by the photographing means and the position of the moving object detected by the position detection means to a base station,
When the base station detects a shooting failure based on the analysis result of the video data, the base station transmits flight information for reshooting to the control means via the communication means,
The unmanned mobile object according to claim 1, wherein the control means controls the moving means and the photographing means based on the flight information transmitted from a base station.

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