Overhead line mapping device and driver support system

Abstract

To suitably create map data on aerial wires.SOLUTION: A flying body 40 comprises a distance sensor 425 as a millimeter wave radar for detecting aerial wires PL and a control part 48. The control part 48 creates map data having position information on the aerial wires PL, detected by the millimeter wave radar, recorded. Namely, it is hard to detect thin aerial wires PL with a camera because of its resolution, but with the milimeter wave rader being applied, metal in the aerial wires PL reflects millimeter waves intensely, which is utilized to enable the aerial wires PL to be suitably detected.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an overhead line map creation device and a driving support system.

Background Art

[0002] In Patent Document 1, a camera mounted on a drone (unmanned aerial vehicle) captures images of ground objects and overhead lines (power transmission lines), and position information (coordinates) of the objects and overhead lines is calculated based on these images.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] However, it is sometimes difficult to detect thin overhead lines from images captured by a camera. That is, depending on the distance from the overhead line, the resolution of the size of the overhead line may not be obtained.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to suitably create map data of overhead lines.

Means for Solving the Problem

[0006] The overhead line map creation device according to the present invention includes: a millimeter wave radar that detects an overhead line; and map creation means for creating a map that records position information of the overhead line detected by the millimeter wave radar, and 、 The aforementioned millimeter-wave radar is mounted on an unmanned aerial vehicle. The control means for the unmanned aerial vehicle is, When overhead lines are detected by the aforementioned millimeter-wave radar, After moving the airframe of the unmanned aerial vehicle to a predetermined distance and horizontal position from the overhead line, The aircraft is moved along the overhead lines while detecting them with the aforementioned millimeter-wave radar. .

[0007] A driving support system according to the present invention comprises: an unmanned aerial vehicle equipped with a millimeter-wave radar that detects overhead wires; a construction machine configured to be able to communicate with said unmanned aerial vehicle; which is a driving support system, wherein a control means of said construction machine creates a map in which position information of overhead wires detected by said millimeter-wave radar is recorded death, The control means for the unmanned aerial vehicle is, When overhead lines are detected by the aforementioned millimeter-wave radar, After moving the airframe of the unmanned aerial vehicle to a predetermined distance and horizontal position from the overhead line, The aircraft is moved along the overhead lines while detecting them with the aforementioned millimeter-wave radar. . Effects of the Invention

[0008] According to the present invention, map data of overhead wires can be suitably created. Brief Description of the Drawings

[0009] [Figure 1] It is a conceptual diagram of the driving support system according to an embodiment. [Figure 2] It is a block diagram showing the control configuration of the driving support system according to an embodiment. [Figure 3] (a) is a diagram for explaining the resolution of a distance sensor, and (b) is a diagram showing a configuration example of a transmission antenna and a reception antenna of the distance sensor. [Figure 4] It is a flowchart showing the flow of map creation processing according to an embodiment. [Figure 5] It is a diagram for explaining the map creation processing according to an embodiment. [Figure 6] It is a diagram for explaining the map creation processing according to an embodiment. Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0011] [Overall Configuration of Driving Support System] Fig. 1 is a conceptual diagram of a driving support system 100 according to the present embodiment, and Fig. 2 is a block diagram showing a schematic control configuration of the driving support system 100. As shown in Fig. 1, the driving support system 100 collects information around a crane 20 including an overhead line PL or the like to support the operation of the crane 20, and includes the crane 20, an aircraft 40, and an information terminal 60.

[0012] [Configuration of Crane] The crane 20 is a so-called mobile crawler crane. Specifically, the crane 20 includes a self-propelled crawler-type lower traveling body 22 and an upper rotating body 23 rotatably mounted on the lower traveling body 22. In the following description, the front-rear and left-right directions as viewed from an occupant (operator) of the crane 20 are defined as the front-rear and left-right directions of the crane 20.

[0013] A boom 24 is attached to the front side of the upper rotating body 23 so as to be capable of being raised and lowered. A counterweight 25 for balancing the weight of the boom 24 and a suspended load is attached to a rear portion of the upper rotating body 23. A cabin 26 in which an operator sits to operate the crane 20 is disposed on the right front portion of the upper rotating body 23.

[0014] The raising and lowering operation of the boom 24 is performed by winding or unwinding a wire rope (hoisting rope) 241 by a hoisting winch (not shown). One end of a hoisting rope 242 is connected to a hook 243 at the tip (upper end) of the boom 24. The other end of the hoisting rope 242 is wound around a hoisting winch (not shown) on the upper rotating body 23, and the hook 243 is lifted and lowered by driving the hoisting winch.

[0015] As shown in Figure 2, the crane 20 further includes a drive unit 31, an operation unit 32, a display unit 33, a communication unit 34, a storage unit 37, and a control unit 38.

[0016] The drive unit 31 is a drive source that operates various parts of the crane 20, and includes the luffing winch and hoisting winch mentioned above, as well as various motors and actuators. The control unit 32 is an operating means that the operator uses to perform various operations. The control unit 32 includes, for example, a handle, pedals, levers, various buttons, etc., and outputs operation signals to the control unit 38 according to the content of these operations.

[0017] The display unit 33 is, for example, a liquid crystal display, an organic electroluminescent display, or other display, and displays various information based on display signals input from the control unit 38. The display unit 33 may also be a touch panel that also functions as part of the operation unit 32. The communication unit 34 is a communication device capable of sending and receiving various types of information directly (or indirectly via a communication network, etc.) between the aircraft 40 and the information terminal 60, etc.

[0018] The memory unit 37 is a memory composed of, for example, RAM (Random Access Memory) or ROM (Read Only Memory), and stores various programs and data, as well as functioning as a workspace for the control unit 38. The control unit 38 is composed of, for example, a CPU (Central Processing Unit) and controls the operation of each part of the crane 20. Specifically, the control unit 38 operates the drive unit 31 based on operator input, loads programs pre-stored in the memory unit 37, and performs various processes in cooperation with the loaded programs.

[0019] [Configuration of the flying object] The aircraft 40 is a so-called drone, an unmanned aircraft (unmanned aerial vehicle) that has multiple rotors and flies by controlling the output of the motors that drive each rotor, and is capable of freely performing movements such as ascending and descending, moving forward, backward, left, and right, and turning in both forward and reverse directions. The aircraft 40 flies around the crane 20 and collects information such as the location of overhead power lines (PL) and buildings. Overhead power lines (PL) refer to wires that are stretched in the air by utility poles or towers, such as power transmission lines.

[0020] Specifically, the aircraft 40 includes a camera 41, a positioning sensor 421, an angular velocity sensor 422, an acceleration sensor 424, a distance sensor 425, a drive unit 43, a communication unit 44, a storage unit 47, and a control unit 48. The overhead line map creation device according to the present invention includes a distance sensor 425 and a control unit 48.

[0021] The camera 41 is supported and directed from the aircraft 40 in a predetermined direction, and captures images of the scene in front of its line of sight according to the orientation of the aircraft. The camera 41 can continuously acquire captured images at a constant frame rate. The image signals obtained by the capture are synthesized and converted into captured image data in a predetermined format by an image processing unit connected to the camera 41, and recorded in the storage unit 47. Furthermore, camera 41 is not limited to one that acquires images in visible light; an infrared camera that captures infrared light may also be used. When an infrared camera is used, distance image data can be obtained using methods such as phase difference imaging. Also, camera 41 is not limited to a monocular camera; a stereo camera may also be used. In this case as well, distance image data can be obtained.

[0022] The positioning sensor 421 is a GNSS (Global Navigation Satellite System) receiver that measures the current position (including altitude) of the aircraft 40. In this embodiment, the positioning sensor 421 employs RTK (Real Time Kinematic), which enables more accurate positioning by combining positioning using satellites such as GPS (Global Positioning System) with position information from a reference station installed on the ground. The angular velocity sensor 422 is, for example, a three-axis gyro azimuth sensor that detects the direction of travel and the tilt angle of the aircraft 40. The acceleration sensor 424 detects acceleration in the X, Y, and Z axes defined for the aircraft 40. The attitude of the aircraft can be determined from the gravitational acceleration detected for each of these axes.

[0023] The distance sensor 425 is mounted on the aircraft 40 in a predetermined direction (for example, forward), acquires distance information within the measurement area in that predetermined direction, and outputs the result to the control unit 38. The distance sensor 425 is a millimeter-wave radar, and as shown in Figure 3(a), its antenna is configured to have good resolution for distance D and the angle in the vertical direction V, and to be able to detect in two dimensions with suppressed horizontal beam spread angle (irradiation angle) α, and is mounted on the aircraft 40. In this case, the vertical direction V corresponds to the up and down direction of the aircraft 40, and the horizontal direction corresponds to the left and right direction of the aircraft 40. The transmitting antenna 426 and receiving antenna 427 of the distance sensor 425 are both array antennas, as shown in Figure 3(b), for example, with multiple patch antennas 426a and 427a arranged on a printed circuit board (PCB). The multiple patch antennas 426a and 427a are arranged on the PCB in a direction corresponding to the left-right direction of the aircraft (left-right direction in Figure 3(b)) in order to suppress the horizontal beam divergence angle α. The receiving antenna 427 has multiple sets of multiple patch antennas 427a arranged in the left-right direction, arranged in a direction corresponding to the up-down direction of the aircraft (up-down direction in Figure 3(b)) in order to have good resolution in the vertical direction V (corresponding to the up-down direction of the aircraft). Furthermore, the antennas of the distance sensor 425 (transmitting antenna 426 and receiving antenna 427) should have higher vertical resolution than horizontal resolution, and a smaller horizontal beam divergence angle α than vertical resolution. The characteristics of such millimeter-wave radars are reversed in terms of the relationship between the vertical and horizontal directions compared to those commonly used, for example, in automotive applications. Furthermore, the various sensors 421 to 425 described above only need to be capable of detecting the desired information, and their types and detection principles are not limited to those described above. For example, altitude sensors, barometric pressure sensors, etc., may be included as needed.

[0024] As shown in Figure 2, the drive unit 43 is configured to output thrust for the movement of the aircraft 40, and has multiple rotors and multiple motors, which are rotational drive sources, provided on each rotor. The drive unit 43 is controlled by the control unit 48 so that the aircraft moves in the direction of the target's movement. The communication unit 44 is a communication device capable of sending and receiving various types of information directly (or indirectly via a communication network, etc.) between the crane 20 and the information terminal 60, etc.

[0025] The memory unit 47 is a memory composed of, for example, RAM (Random Access Memory) or ROM (Read Only Memory), and stores various programs and data, as well as functioning as a workspace for the control unit 38. Specifically, the memory unit 47 pre-stores the flight control program for the aircraft 40, map data (basic map data) of the area around the crane 20's work area, as well as image data acquired by the camera 41 and detection data detected by various sensors.

[0026] The control unit 48 is composed of, for example, a CPU (Central Processing Unit) and comprehensively controls each part of the aircraft 40 based on control programs stored in the memory unit 47 and control commands transmitted from the information terminal 60. For example, the control unit 48 operates the drive unit 43 and various sensors based on control commands from the information terminal 60, and deploys programs pre-stored in the memory unit 47 and executes various processes in cooperation with the deployed programs.

[0027] [Configuration of information terminals] The information terminal 60 is responsible for operating (remotely controlling) the aircraft 40 and processing data acquired by the aircraft 40. Specifically, the information terminal 60 comprises an operation unit 61, a display unit 62, a communication unit 64, a storage unit 67, and a control unit 68.

[0028] The operation unit 61 is an operating means that allows the operator to perform various operations to operate the information terminal 60, and includes, for example, a pointing device such as a mouse or keyboard. The display unit 62 is, for example, a liquid crystal display, an organic electroluminescent display, or other display, and displays various information based on display signals input from the control unit 68. The display unit 62 may also be a touch panel that also serves as at least a part of the operation unit 61. The communication unit 64 is a communication device capable of sending and receiving various types of information directly (or indirectly via a communication network, etc.) between the crane 20 and the aircraft 40, etc.

[0029] The memory unit 67 is a memory composed of, for example, RAM (Random Access Memory) or ROM (Read Only Memory), and stores various programs and data, as well as functioning as a workspace for the control unit 68. Specifically, the memory unit 67 stores, for example, various data transmitted from the aircraft 40. The control unit 68 is composed of, for example, a CPU (Central Processing Unit) and controls the operation of each part of the information terminal 60. Specifically, the control unit 68 deploys a program pre-stored in the storage unit 67 based on the operation content of the operation unit 61, and performs various processes in cooperation with the deployed program.

[0030] [Map creation process] Next, we will explain the map creation process that creates map data for the area around crane 20. Figure 4 is a flowchart showing the flow of the map creation process, and Figures 5 and 6 are diagrams illustrating the map creation process.

[0031] The map creation process is a process of creating map data that records information about the surrounding environment that may affect the operation of the crane 20, in advance of the operation. Information about the surrounding environment includes topographic information such as mountains and rivers, as well as information about land use such as roads, railways, and buildings, and in this embodiment, it includes the location information of overhead lines PL. Furthermore, the area range of the map data only needs to be a predetermined range around the crane 20 that includes at least the work area of ​​the crane 20. This map creation process is performed, for example, by the control unit 68 of the information terminal 60 reading the corresponding program from the storage unit 67 and expanding it based on the user's operation of the information terminal 60.

[0032] As shown in Figure 4, once the map creation process is executed, the control unit 68 of the information terminal 60 starts the flight of the aircraft 40 (step S1). In this case, the flight path is not particularly limited as long as it allows for the detection and photography of the overhead wires PL across the entire working area of ​​the crane 20, and does not have to be a pre-set path.

[0033] Next, the control unit 48 of the aircraft 40 takes pictures of the area around the crane 20 using the camera 41 and acquires information about the surrounding environment of the crane 20 (terrain information and location information of buildings, etc.) from the images (step S2). Then, the control unit 48 records the acquired information about the surrounding environment of the crane 20 into map data (basic map data) read from the storage unit 47. The basic map data is of the area around the work area of ​​the crane 20 and, for example, has pre-existing topographic information. However, the information that the basic map data has pre-existing is not particularly limited. Also, the map data does not have to be based on the basic map data and may be newly created in step S2. Furthermore, the detection (extraction) method for buildings, etc., based on the image acquired by the camera 41 can utilize conventionally known methods.

[0034] Next, the control unit 48 detects the overhead wire PL using the distance sensor 425 (millimeter-wave radar) (step S3; Figure 5). Here, by applying millimeter-wave radar, the property that metals within the overhead wire PL (such as copper wires contained in electric wires) strongly reflect millimeter waves can be utilized to suitably detect the overhead wire PL. At this time, the control unit 48 determines the direction of the overhead line PL from the rotation direction of the aircraft 40, and determines the distance D to the overhead line PL and its elevation angle θ using the distance sensor 425. Various state variables of the aircraft 40 are obtained from sensors (positioning sensor 421, angular velocity sensor 422, acceleration sensor 424, etc.). The altitude of the aircraft 40 is obtained from the positioning sensor 421.

[0035] Next, the control unit 48 flies the aircraft 40 to point A, which is at a predetermined distance Da and elevation angle θa (step S4; Figure 6). The position of point A (relative position to the overhead line PL) is not particularly limited, but for example, it is a position at a predetermined distance Da that is relatively close to the overhead line PL, and where the elevation angle θa = zero (horizontal position of a certain part of the overhead line PL). The control unit 48 may also use the camera 41 to confirm that the object being measured is an overhead wire PL after the aircraft 40 has reached point A.

[0036] Next, the control unit 48 moves the aircraft 40 along the overhead wire PL while maintaining a predetermined distance Da and elevation / depression angle θa from the overhead wire PL, based on measurements by the distance sensor 425 (step S5). This allows the aircraft 40 to fly along the sag (looseness) of the overhead wire PL. Then, while moving the aircraft 40, the control unit 48 acquires the three-dimensional position (latitude, longitude, altitude) of the overhead line PL detected by the distance sensor 425, and records this position information in the map data read from the storage unit 67. This map data contains the information acquired by the camera 41 in step S2. This creates three-dimensional map data that records the position information of the overhead line PL. The created map data is then transmitted, for example, to the crane 20 and the information terminal 60.

[0037] Next, the control unit 48 determines whether or not to terminate the map creation process (step S6). If it determines not to terminate the process (step S6; No), it proceeds to step S2 described above. As a result, the processes in steps S2 to S5 are repeated, and the creation and updating of map data continues. Then, if the control unit determines that the map creation process should be terminated, for example, by completing the creation of map data for the entire work area of ​​the crane 20 (step S6; Yes), the control unit 48 terminates the map creation process and sends a signal to the information terminal 60 to that effect.

[0038] In this way, map data including the location information of the overhead wire PL is created. The created map data may be used in the crane 20 for operation control to avoid contact between the boom 24, etc., and the overhead wire PL (or to warn if there is a risk of contact), or it may be displayed on the display unit 33 to assist the operator's operation. Alternatively, it may be displayed on the display unit 62 of the information terminal 60 to present the location information of the overhead wire PL, etc., to users such as those involved in the work.

[0039] [Technical effects of this embodiment] As described above, according to this embodiment, overhead power lines PL are detected by the distance sensor 425, which is a millimeter-wave radar, and map data is created that records the position information of these overhead power lines PL. In other words, while cameras may have difficulty detecting thin overhead wires (PLs) due to resolution issues, the application of millimeter-wave radar allows for the effective detection of overhead wires by utilizing the property that metals within the PLs (such as copper wires contained in power lines) strongly reflect millimeter waves. Therefore, map data of overhead wires can be effectively created.

[0040] Furthermore, according to this embodiment, by creating map data of local overhead power lines (PL) at construction sites in advance, it is possible to understand the safe aerial range of construction machinery such as the crane 20 and perform operation control to avoid contact with the overhead power lines (PL).

[0041] Furthermore, according to this embodiment, the antenna of the distance sensor 425 has higher resolution in the vertical direction than in the horizontal direction. This allows for the effective detection of overhead wires PL stretched horizontally or in a similar direction. Although the beam divergence angle α in the horizontal direction is smaller than that in the vertical direction, this is compensated for by the movement (movement, etc.) of the aircraft 40 itself, so there is no problem.

[0042] Furthermore, according to this embodiment, when the distance sensor 425 detects an overhead wire PL, the aircraft 40 is moved to a predetermined relative position to the overhead wire PL, and then the aircraft is moved along the overhead wire while the distance sensor 425 continues to detect the overhead wire PL. As a result, once the overhead line PL is detected, map data can be suitably created. Furthermore, even if the overhead line PL has slack, the aircraft 40 can be suitably moved along the slackened overhead line PL.

[0043] [others] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments and their modifications. For example, in the above embodiment, map data containing positional information of overhead lines PL is used to operate the crane 20, but the use of such map data is not particularly limited. For example, a navigation system may be configured to generate a flight path for the aircraft 40 using this map data and to enable autonomous flight of the aircraft 40. This allows the aircraft to fly the shortest path to the destination while taking into account the position of the overhead lines PL. In this case, the path generation (path modification) may be done before or during the actual (live) flight.

[0044] Furthermore, in the above embodiment, information about the surrounding environment of the crane 20 acquired by the camera 41 and the position information of the overhead wire PL acquired by the distance sensor 425 are recorded in the map data. However, information other than the position information of the overhead wire PL may be acquired by sensors other than the camera 41, by sensors installed on something other than the aircraft 40 (for example, the crane 20), or may be included in the basic map data in advance. Also, the map data does not need to contain information other than the position information of the overhead wire PL.

[0045] Furthermore, in the above embodiment, the control unit 48 of the aircraft 40 performs the main processing, but the control unit 38 of the crane 20 or the control unit 68 of the information terminal 60 may receive images from the camera 41 and detection results from the distance sensor 425 from the aircraft 40 and create map data based on them. Also, the millimeter-wave radar does not have to be mounted on the aircraft 40. In other words, the overhead line map creation device according to the present invention only needs to include a millimeter-wave radar and means for creating a map that records the position information of the overhead lines detected by the millimeter-wave radar.

[0046] Furthermore, although a so-called crawler crane was exemplified as crane 20 in the above embodiment, the type of crane is not particularly limited and may include any crane, such as crawler cranes, wheel cranes, truck cranes, port cranes, overhead cranes, gantry cranes, unloaders, and fixed cranes, in addition to mobile cranes such as crawler cranes, wheel cranes, and truck cranes. Furthermore, the construction machinery according to the present invention is not limited to cranes, but broadly includes construction machinery such as excavators that may come into contact with overhead lines during operation.

[0047] Furthermore, details shown in the above embodiments can be modified as appropriate without departing from the spirit of the invention. [Explanation of Symbols]

[0048] 20. Cranes (construction machinery) 38 Control Unit 40. Aircraft (Unmanned Aerial Vehicles) 41 Camera 47 Memory section 48 Control Unit 60 Information terminals 68 Control Unit 100 Driver Assistance Systems 425 Distance Sensor (Millimeter-wave Radar) PL overhead line α Horizontal beam divergence angle (beam irradiation angle)

Claims

1. A millimeter-wave radar that detects overhead lines, A mapping means for creating a map that records the position information of overhead lines detected by the aforementioned millimeter-wave radar, Equipped with, The aforementioned millimeter-wave radar is mounted on an unmanned aerial vehicle. The control means for the unmanned aerial vehicle is, When overhead lines are detected by the aforementioned millimeter-wave radar, After moving the airframe of the unmanned aerial vehicle to a predetermined distance and horizontal position from the overhead line, The aircraft is moved along the overhead lines while detecting them with the aforementioned millimeter-wave radar. Overhead line map creation device.

2. The antenna of the aforementioned millimeter-wave radar has higher resolution in the vertical direction than in the horizontal direction, and a smaller beam irradiation angle in the horizontal direction than in the vertical direction. The overhead line map creation device according to claim 1.

3. The control means moves the airframe of the unmanned aerial vehicle along the slackened overhead wire when the overhead wire is slack. The overhead line map creation device according to claim 1.

4. The map creation means records the location information of the overhead lines on map information that already contains topographic information. The overhead line map creation device according to claim 1.

5. An unmanned aerial vehicle equipped with a millimeter-wave radar that detects overhead lines, A construction machine configured to communicate with the aforementioned unmanned aerial vehicle, A driver assistance system equipped with, The control means for the construction machine creates a map that records the position information of the overhead lines detected by the millimeter-wave radar, The control means for the unmanned aerial vehicle is, When overhead lines are detected by the aforementioned millimeter-wave radar, After moving the airframe of the unmanned aerial vehicle to a predetermined distance and horizontal position from the overhead line, The aircraft is moved along the overhead lines while detecting them with the aforementioned millimeter-wave radar. Driver assistance system.

Images