Approach detection system

Abstract

To provide an approach detection system for accurately detecting an approach of both of vehicles in a dead corner while eliminating the necessity of arrangement of a facility in an area in which the vehicles travel.SOLUTION: An approach detection system 1 includes: a laser sensor 5 for acquiring position information of a vehicle 2; a transceiver 7; an own position estimation section 11; a map storage section 6 for acquiring map information of an area in which the vehicles 2 move; a dead corner generation section 12 for sequentially generating a dead corner Da of the vehicle 2 for each movement of the vehicle 2 based on the position information of the vehicle 2 and the map information; and an approach determination section 13 for determining whether the vehicles 2 are approaching in the dead corner Da of the vehicle 2 successively generated for each movement of the vehicle 2.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a proximity detection system.

Background Art

[0002] As a conventional proximity detection system, for example, the techniques described in Patent Documents 1 and 2 are known. The proximity detection system described in Patent Document 1 includes a notification unit disposed at an intersection or the like. The notification unit has a proximity object detection device and a signal transmission device. When a moving object approaching the notification unit is detected by the proximity object detection device, a signal is transmitted from the signal transmission device to other moving objects approaching the notification unit.

[0003] The proximity detection system described in Patent Document 2 includes a vehicle proximity detection device installed at the center of the road surface of an intersection, a display device installed above the road surface of the intersection, and an in-vehicle device installed in a vehicle. The vehicle proximity detection device detects the distance and speed from the intersection to a vehicle on the road, predicts the time when the vehicle reaches the intersection based on the distance and speed, and when it is determined that a plurality of vehicles enter the intersection simultaneously, a warning display is performed on the display device, and at the same time, an image of the vehicle entering the intersection is transmitted to other vehicles and displayed on the in-vehicle device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in a logistics site, unlike on a general road, shelves and the like are densely packed. Therefore, when applying the technology described in the above prior art to a logistics site, it is necessary to install a lot of equipment for detecting the approach of vehicles such as forklifts on the passageways of the logistics site, which is laborious and costly. Also, in a logistics site, due to the positional relationship between shelves and the like and the vehicles, the blind spots of the vehicles change every moment, but it is necessary to accurately detect the approach of vehicles even in such blind spots.

[0006] An object of the present invention is to provide a proximity detection system that can accurately detect the approach of vehicles in blind spots while eliminating the need to install equipment in the area where the vehicles travel.

Means for Solving the Problem

[0007] (1) One aspect of the present invention is a proximity detection system for detecting the approach of vehicles, including a position information acquisition unit that acquires the position information of the vehicles, a map information acquisition unit that acquires the map information of the area where the vehicles move, and based on the position information of the vehicles acquired by the position information acquisition unit and the map information acquired by the map information acquisition unit, a blind spot generation unit that sequentially generates the blind spots of the vehicles for each movement of the vehicles, and a proximity determination unit that determines whether vehicles are approaching each other in the blind spots of the vehicles sequentially generated for each movement of the vehicles by the blind spot generation unit.

[0008] In such a proximity detection system, the position information of the vehicles is acquired, and the map information of the area where the vehicles move is acquired. Then, based on the position information of the vehicles and the map information, the blind spots of the vehicles are sequentially generated for each movement of the vehicles. And in the blind spots of the vehicles sequentially generated for each movement of the vehicles, it is determined whether vehicles are approaching each other. At this time, based on the positional relationship between the vehicles and the blind spot targets included in the map information, the blind spots of the vehicles that change every moment are automatically and sequentially generated. Thereby, even without installing equipment for detecting the approach of vehicles in the area where the vehicles travel, the approach of vehicles in the blind spots can be accurately detected.

[0009] (2) In the above (1), the position information acquisition unit acquires the position information of the host vehicle and the position information of other vehicles approaching the host vehicle. The blind spot generation unit sequentially generates the blind spots of the host vehicle for each movement of the host vehicle based on the position information of the host vehicle and the map information. The approach determination unit may determine whether or not other vehicles are approaching the host vehicle from within the blind spot of the host vehicle based on the position information of the other vehicles.

[0010] With such a configuration, when there are other vehicles approaching the host vehicle, it is possible to determine whether other vehicles are approaching the host vehicle from within the blind spot of the host vehicle or from outside the blind spot of the host vehicle.

[0011] (3) In the above (2), the approach detection system further includes an alarm unit that gives an alarm when it is determined by the approach determination unit that the vehicles are approaching each other. The alarm unit may give a stronger alarm when it is determined that other vehicles are approaching the host vehicle from within the blind spot of the host vehicle than when it is determined that other vehicles are approaching the host vehicle from outside the blind spot of the host vehicle.

[0012] With such a configuration, when other vehicles are approaching the host vehicle from within the blind spot of the host vehicle, a stronger alarm is given than when other vehicles are approaching the host vehicle from outside the blind spot of the host vehicle. Therefore, for example, it is possible to sufficiently alert the driver of the host vehicle.

[0013] (4) In any of the above (1) to (3), the blind spot generation unit may set a virtual circle centered on the vehicle, divide the virtual circle in the circumferential direction and the radial direction respectively to divide it into a plurality of regions, and extract, as the blind spot of the vehicle, the region hidden from the vehicle by the blind spot target included in the map information among the plurality of regions.

[0014] With such a configuration, based on the positional relationship between the vehicle and the blind spot target included in the map information, the region hidden from the vehicle by the blind spot target within the virtual circle centered on the vehicle is extracted as the blind spot of the vehicle. Therefore, it is possible to easily and surely generate the blind spot of the vehicle that changes every moment.

[0015] (5) In the above (4), the blind spot generation unit may generate a blind spot of the vehicle using an object having a specified height or more as a blind spot target.

[0016] In such a configuration, an object lower than the specified height is not a blind spot target, so that an appropriate blind spot is generated for, for example, a driver in the vehicle. Therefore, it is possible to detect the approach of vehicles in the blind spot in an environment close to an actual site.

Effect of the Invention

[0017] According to the present invention, it is possible to accurately detect the approach of vehicles in the blind spot while eliminating the need to install equipment in the area where the vehicle travels.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiment for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted.

[0020] FIG. 1 is a block diagram showing the configuration of a proximity detection system according to an embodiment of the present invention. In FIG. 1, the proximity detection system 1 of the present embodiment is a system that detects the approach of vehicles 2 (see FIG. 2) to each other when a plurality of vehicles 2 perform a loading and unloading operation while traveling at a logistics site such as inside a factory. The vehicle 2 is an industrial vehicle (see FIG. 11) such as a forklift.

[0021] At the logistics site, as shown in FIG. 2 for example, a plurality of shelves 3 are arranged side by side. The vehicle 2 travels on the passage R between the shelves 3 and performs a loading and unloading operation on the shelf 3. The shelf 3 is an object that becomes a blind spot target for the vehicle 2. The vehicle 2 travels by manual operation by a driver who is an operator.

[0022] The proximity detection system 1 is mounted on the vehicle 2. Here, the own vehicle 2 is referred to as the own vehicle 2A, and the vehicle 2 other than itself is referred to as the other vehicle 2B (see FIG. 8). The proximity detection system 1 includes a laser sensor 5, a map storage unit 6, a transceiver 7, an alarm 8, and a controller 10.

[0023] The laser sensor 5 is a sensor that irradiates a 3D laser around the host vehicle 2A and receives the reflected light of the laser to detect the distance to an object existing around the host vehicle 2A. As the laser sensor 5, for example, LIDAR (light detection and ranging) or a laser rangefinder or the like is used.

[0024] The map storage unit 6 stores map information of the area (logistics site) where the host vehicle 2A moves. The map information includes stationary objects such as the shelf 3. The map storage unit 6 constitutes a map information acquisition unit that acquires map information of the area where the host vehicle 2A moves.

[0025] The map information is a two-dimensional semantic map to which various information can be added. Here, the map information includes the position information of objects such as the shelf 3. The position information of the object is information that becomes the origin (dead angle target) of the blind spot of the host vehicle 2A. The position of the object is represented by two-dimensional plane coordinates (XY coordinates), for example, as shown in FIG. 3. In FIG. 3, the shelf 3 has a rectangular shape in plan view, and the XY coordinates of the four corner portions 3a of the shelf 3 are given as the position information of the object.

[0026] When performing vehicle-to-vehicle communication between a plurality of vehicles 2, the transceiver 7 transmits and receives information including the position information of the vehicle 2. The transceiver 7 receives the position information of the other vehicle 2B transmitted from the other vehicle 2B. The transceiver 7 acquires the position information of the other vehicle 2B approaching the host vehicle 2A.

[0027] The alarm 8 is a device that issues an alarm by emitting a buzzer sound (alarm sound). The alarm 8 may perform an alarm display together with the generation of the buzzer sound.

[0028] The controller 10 is composed of a CPU, a RAM, a ROM, an input / output interface, and the like. The controller 10 includes a self-position estimation unit 11, a dead angle generation unit 12, an approach determination unit 13, and an alarm control unit 14.

[0029] The self - position estimation unit 11 estimates the current self - position of the host vehicle 2A based on the detection data of the laser sensor 5 and the map information stored in the map storage unit 6. Specifically, the self - position estimation unit 11 estimates the self - position of the host vehicle 2A by, for example, using the SLAM (simultaneous localization and mapping) method to match the detection data of the laser sensor 5 and the map information. SLAM is a self - position estimation technology that performs self - position estimation using sensor data and map data. The self - position estimation unit 11 cooperates with the laser sensor 5 to acquire the position information of the host vehicle 2A.

[0030] The laser sensor 5, the self - position estimation unit 11, and the transceiver 7 constitute a position information acquisition unit that acquires the position information of the vehicle 2. The position information of the vehicle 2 includes the planar coordinates of the position of the vehicle 2 and the acquisition time of the position of the vehicle 2.

[0031] The blind - spot generation unit 12 sequentially generates the blind - spots of the host vehicle 2A for each movement of the host vehicle 2A based on the self - position of the host vehicle 2A estimated by the self - position estimation unit 11 and the map information stored in the map storage unit 6.

[0032] As shown in FIG. 4, the blind - spot generation unit 12 sets a virtual circle C centered on the host vehicle 2A, divides the virtual circle C in the circumferential direction and the radial direction respectively to divide it into a plurality of regions Ac, and extracts, as the blind - spot Da of the host vehicle 2A, the region Ac among the plurality of regions Ac that is hidden from the host vehicle 2A by blind - spot targets such as the shelf 3 included in the map information.

[0033] In the example shown in FIG. 4, on the right side of the passage R1 where the host vehicle 2A travels, a shelf 3A extending along the passage R1 is installed. On the left side of the passage R1 where the host vehicle 2A travels, two shelves 3B are installed side by side along the passage R1, and a passage R2 is provided between the two shelves 3B. FIG. 4(b) shows a state where the host vehicle 2A has advanced further than in FIG. 4(a).

[0034] Specifically, the blind spot Da of the host vehicle 2A is set within a virtual circle C with a radius r (see FIG. 8) centered on a designated position of the host vehicle 2A (for example, the center position of the driver's seat). The radius r is, for example, 10 m. The virtual circle is divided into n parts (here, 24 parts) in the circumferential direction and m parts (here, 5 parts) in the radial direction. Therefore, the virtual circle C is divided into (n × m) regions Ac.

[0035] For each region Ac within the virtual circle C, it is determined whether it is a blind spot Da based on the relationship between the current position of the host vehicle 2A and the positions of the shelves 3A and 3B. If the front end (inner end) Ace of the region Ac with respect to the center of the virtual circle C is not entirely hidden by the shelves 3A and 3B, it is assumed that the inner end Ace of the region Ac can be seen, and the region Ac is not a blind spot. If the inner end Ace of the region Ac with respect to the center of the virtual circle C is entirely hidden by the shelves 3A and 3B, it is assumed that the inner end Ace of the region Ac cannot be seen, and the region Ac and the region Ac existing radially outside the region Ac are blind spots Da.

[0036] Also, it is determined whether the two corner points Acp on the front side of the region Ac with respect to the center of the virtual circle C are hidden by the shelves 3A and 3B. When the two corner points Acp are hidden by the shelves 3A and 3B, the region Ac having the two corner points Acp and the region Ac existing radially outside the region Ac may be set as the blind spot Da.

[0037] By generating the blind spot Da of the host vehicle 2A in this way, as shown in FIG. 5, the blind spot Da of the host vehicle 2A changes moment by moment. Note that the driving area shown in FIG. 5 is the same as that in FIG. 4. As the host vehicle 2A approaches the passage R2, the range of the blind spot Da of the host vehicle 2A becomes narrower.

[0038] Returning to FIG. 1, the approach determination unit 13 determines whether the host vehicle 2A and the other vehicle 2B are approaching each other in the blind spot Da of the host vehicle 2A sequentially generated each time the host vehicle 2A moves by the blind spot generation unit 12. The approach determination unit 13 determines whether the other vehicle 2B is approaching the host vehicle 2A from within the blind spot Da of the host vehicle 2A based on the position information of the other vehicle 2B acquired by the transceiver 7.

[0039] FIG. 6 is a flowchart showing the procedure of the approach determination process executed by the approach determination unit 13. At the start of this process, a discrimination flag is set to 0.

[0040] In FIG. 6, the approach determination unit 13 first acquires the position information of the other vehicle 2B received by the transceiver 7 (step S101). Then, the approach determination unit 13 determines whether the other vehicle 2B is approaching the host vehicle 2A based on the position information of the other vehicle 2B (step S102).

[0041] When the approach determination unit 13 determines that the other vehicle 2B is approaching the host vehicle 2A, it determines whether the other vehicle 2B exists within the blind spot Da of the host vehicle 2A generated by the blind spot generation unit 12 based on the position information of the other vehicle 2B (step S103). When the approach determination unit 13 determines that the other vehicle 2B exists within the blind spot Da of the host vehicle 2A, it sets the discrimination flag to A (step S104) and executes the above step S101 again.

[0042] When the approach determination unit 13 determines that the other vehicle 2B does not exist within the blind spot Da of the host vehicle 2A, it sets the discrimination flag to B (step S105) and executes the above step S101 again. When the approach determination unit 13 determines in step S102 that the other vehicle 2B is not approaching the host vehicle 2A, it executes the above step S101 again.

[0043] Returning to FIG. 1, when the approach determination unit 13 determines that the vehicles 2 are approaching each other, the warning control unit 14 controls the alarm device 8 to give a warning. When the approach determination unit 13 determines that the other vehicle 2B is approaching the host vehicle 2A from within the blind spot Da of the host vehicle 2A, the warning control unit 14 controls the alarm device 8 to give a stronger warning than when it is determined that the other vehicle 2B is approaching the host vehicle 2A from outside the blind spot Da of the host vehicle 2A. The warning control unit 14 cooperates with the alarm device 8 to constitute a warning unit that gives a warning when the approach determination unit 13 determines that the vehicles 2 are approaching each other.

[0044] FIG. 7 is a flowchart showing the procedure of the warning control process executed by the warning control unit 14. In FIG. 7, the warning control unit 14 first determines whether the discrimination flag is not 0 (step S111).

[0045] When the warning control unit 14 determines that the discrimination flag is not 0, it determines whether the discrimination flag is A (step S112). When the warning control unit 14 determines that the discrimination flag is A, it controls the alarm 8 to generate a loud buzzer sound (step S113) and executes the above step S111 again.

[0046] When the warning control unit 14 determines that the discrimination flag is not A but B, it controls the alarm 8 to generate a small buzzer sound (step S114) and executes the above step S111 again.

[0047] Therefore, warnings are given with priority when the other vehicle 2B approaches the host vehicle 2A from within the blind spot Da of the host vehicle 2A and when the other vehicle 2B approaches the host vehicle 2A from outside the blind spot Da of the host vehicle 2A.

[0048] Specifically, as shown in FIG. 8, when there is an other vehicle 2B approaching the host vehicle 2A from within the blind spot Da of the host vehicle 2A, a loud buzzer sound is generated from the alarm 8 regardless of the presence or absence of an other vehicle 2B approaching the host vehicle 2A from outside the blind spot Da of the host vehicle 2A. That is, when there is an other vehicle 2B approaching the host vehicle 2A only from within the blind spot Da of the host vehicle 2A, or when there are a plurality of other vehicles 2B approaching the host vehicle 2A from within and outside the blind spot Da of the host vehicle 2A, a loud buzzer sound is generated from the alarm 8.

[0049] On the other hand, when there is an other vehicle 2B approaching the host vehicle 2A from outside the blind spot Da of the host vehicle 2A but there is no other vehicle 2B approaching the host vehicle 2A from within the blind spot Da of the host vehicle 2A, a small buzzer sound is generated from the alarm 8.

[0050] By the way, when an approach detection device that detects the approach of vehicles is installed on the traveling road at a logistics site, such as an intersection on a general road, the following problems occur. That is, in a logistics site, as shown in FIG. 9, since shelves 3 and the like are densely arranged, the number of approach detection devices 50 installed on the passage R increases. Further, as the number of installed approach detection devices 50 increases, it is necessary to additionally provide power sources for the approach detection devices 50 accordingly. For this reason, the construction work becomes troublesome and the installation cost increases.

[0051] Further, as shown in FIG. 10, although the presence or absence of another vehicle 2B approaching the host vehicle 2A can be recognized by the approach detection device 50, it is not known whether the other vehicle 2B is approaching from within the blind spot of the host vehicle 2A or from outside the blind spot of the host vehicle 2A.

[0052] In response to such problems, in the present embodiment, the position information of the vehicle 2 is acquired, and the map information of the logistics site, which is the area where the vehicle 2 moves, is acquired. Then, based on the position information of the vehicle 2 and the map information, the blind spot Da of the vehicle 2 is sequentially generated every time the vehicle 2 moves. Then, it is determined whether the vehicles 2 are approaching each other in the blind spot Da of the vehicle 2 sequentially generated every time the vehicle 2 moves. At this time, based on the positional relationship between the vehicle 2 and the blind spot targets such as the shelf 3 included in the map information, the blind spot Da of the vehicle 2 that changes every moment is automatically and sequentially generated. Thereby, even if facilities such as the approach detection device 50 for detecting the approach of the vehicles 2 to each other are not installed at the logistics site, the approach of the vehicles 2 to each other in the blind spot Da can be accurately detected.

[0053] Further, in the present embodiment, when there is another vehicle 2B approaching the host vehicle 2A, it is possible to determine whether the other vehicle 2B is approaching the host vehicle 2A from within the blind spot Da of the host vehicle 2A or from outside the blind spot Da of the host vehicle 2A.

[0054] In addition, in the present embodiment, when another vehicle 2B approaches the host vehicle 2A from within the blind spot Da of the host vehicle 2A, a stronger warning is issued compared to when another vehicle 2B approaches the host vehicle 2A from outside the blind spot Da of the host vehicle 2A. Therefore, it is possible to sufficiently alert the driver of the host vehicle 2A and the workers at the logistics site.

[0055] In addition, in the present embodiment, based on the positional relationship between the vehicle 2 and blind spot targets such as the shelf 3 included in the map information, an area Ac that is hidden from the vehicle 2 by the blind spot target within a virtual circle C centered on the vehicle 2 is extracted as the blind spot Da of the vehicle 2. Therefore, it is possible to easily and surely generate the blind spot Da of the vehicle 2 that changes moment by moment.

[0056] Note that the present invention is not limited to the above embodiment. For example, in the above embodiment, the map information stored in the map storage unit 6 is a two-dimensional semantic map, but the map information is not particularly limited in its form, and a three-dimensional map may be used. In a three-dimensional map, the position of an object such as the shelf 3 is represented by XYZ coordinates obtained by adding a height position to the plane coordinates.

[0057] In this case, as shown in FIG. 11, the blind spot generation unit 12 generates the blind spot Da of the vehicle 2 using the shelf 3 having a height equal to or higher than the specified height as the blind spot target. That is, the shelf 3C having a height equal to or higher than the specified height becomes the blind spot target, but the shelf 3D having a height lower than the specified height does not become the blind spot target. The specified height is, for example, the height of the driver's seat of the host vehicle 2A.

[0058] By generating the blind spot Da of the vehicle 2 using an object such as the shelf 3 having a height equal to or higher than the specified height as the blind spot target in this way, an object having a height lower than the specified height does not become the blind spot target. Therefore, an appropriate blind spot Da is generated for the driver riding in the host vehicle 2A, for example. Therefore, it is possible to detect the approach of the vehicles 2 in the blind spot Da in an environment close to an actual logistics site.

[0059] In addition, in the above-described embodiment, the self-position of the vehicle 2 is estimated using the SLAM method. However, as the self-position estimation technology, it is not particularly limited to the SLAM method, and a satellite positioning system (GNSS / GPS), an inertial measurement unit (IMU), or the like may be used.

[0060] In addition, in the above-described embodiment, the vehicle 2 is traveling by manual driving. However, it is not particularly limited to that form, and the vehicle 2 may be driven by autonomous driving.

[0061] In addition, in the above-described embodiment, the vehicle 2, which is an industrial vehicle, is traveling in a logistics site such as a factory. However, it is not particularly limited to that form. For example, in an area where blind spots change every moment, a vehicle 2 such as a passenger car may be driven.

Explanation of Reference Numerals

[0062] 1... Proximity Detection System, 2... Vehicle, 2A... Own Vehicle, 2B... Other Vehicle, 3... Shelf (Object), 3A to 3C... Shelf (Blind Spot Target), 5... Laser Sensor (Position Information Acquisition Unit), 6... Map Storage Unit (Map Information Acquisition Unit), 7... Transceiver (Position Information Acquisition Unit), 8... Alarm (Alarm Unit), 11... Self-Position Estimation Unit (Position Information Acquisition Unit), 12... Blind Spot Generation Unit, 13... Proximity Determination Unit, 14... Alarm Control Unit (Alarm Unit), C... Virtual Circle, Ac... Area, Da... Blind Spot.

Claims

1. A proximity detection system for detecting the proximity of vehicles, comprising: A position information acquisition unit that acquires the position information of the vehicle; A map information acquisition unit that acquires map information of the area where the vehicle moves; A blind spot generation unit that sequentially generates blind spots of the vehicle for each movement of the vehicle based on the position information of the vehicle acquired by the position information acquisition unit and the map information acquired by the map information acquisition unit; A proximity detection system comprising a proximity determination unit that determines whether the vehicles are approaching each other in the blind spots of the vehicle sequentially generated for each movement of the vehicle by the blind spot generation unit.

2. The position information acquisition unit acquires the position information of the host vehicle and the position information of other vehicles approaching the host vehicle, The blind spot generation unit sequentially generates blind spots of the host vehicle for each movement of the host vehicle based on the position information of the host vehicle and the map information, The proximity determination unit determines whether the other vehicle is approaching the host vehicle from within the blind spot of the host vehicle based on the position information of the other vehicle. The proximity detection system according to claim 1.

3. Further comprising an alarm unit that gives an alarm when it is determined by the proximity determination unit that the vehicles are approaching each other, When it is determined that the other vehicle is approaching the host vehicle from within the blind spot of the host vehicle, the alarm unit gives a stronger alarm than when it is determined that the other vehicle is approaching the host vehicle from outside the blind spot of the host vehicle. The proximity detection system according to claim 2.

4. The blind spot generation unit sets a virtual circle centered on the vehicle, divides the virtual circle in the circumferential direction and the radial direction respectively into a plurality of regions, and extracts, as the blind spot of the vehicle, the regions hidden from the vehicle by the blind spot targets included in the map information among the plurality of regions. The proximity detection system according to claim 1.

5. The blind spot generation unit generates a blind spot of the vehicle using an object having a specified height or more as the blind spot target, according to the proximity detection system of claim 4.

Images