Perimeter Monitoring System

Abstract

A detection object 26a is provided to an object to be identified, and is, with respect to a periphery monitoring sensor which uses infrared light, configured to be seen such that the detection object is moving relative to the object to be identified.

Description

[Technical field]

[0001] The present invention relates to a detection object and a periphery monitoring system. [Background technology]

[0002] Conventionally, various perimeter monitoring sensors have been proposed that detect and identify objects around a vehicle and assist in driving the vehicle. For example, a perimeter monitoring sensor called LiDAR (Light Detection and Ranging) that uses infrared light is known. In addition, a LiDAR provided inside a vehicle lamp has also been proposed as one of the suitable locations for detecting objects around the vehicle (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-164916 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the detection accuracy of LiDAR depends on the number and shape of point clouds, the accuracy of object identification decreases when the number of point clouds decreases or when objects with similar shapes are detected. In addition, perimeter monitoring sensors that use infrared light have difficulty distinguishing the color of objects.

[0005] The present invention has been made in view of the above circumstances, and one of its exemplary purposes is to provide a new technique for improving the accuracy of identifying surrounding objects. [Means for solving the problem]

[0006] In order to solve the above problems, a detectable object in one embodiment of the present invention is a detectable object that is provided on an object to be identified, and is configured so that the detectable object appears to move relative to the object to be identified to a peripheral monitoring sensor that utilizes infrared light.

[0007] According to this embodiment, by utilizing information based on the observed movement of the detected object, it is possible to improve the accuracy of identifying surrounding objects.

[0008] The object to be identified may be a moving object, and the detected object may be configured so that the detected object appears to move differently from the moving object to the periphery monitoring sensor. In this way, the detected object appears to move differently from the moving object, and characteristic information as to, for example, where on the moving object the detected object is located can be obtained.

[0009] The infrared light reflecting area may be configured to change its reflection position or reflection direction. This makes it easier for the detected object to appear to move differently from the movement of the moving object, making it easier to determine where on the moving object the detected object is located. In addition, the detected object may be multiple objects on the moving object. This makes it possible to determine the orientation of the moving object based on the relative positions of the multiple detected objects.

[0010] The area from which the infrared light is emitted may be configured to change, which makes it easier to see the movement of the detected object as being different from the movement of the moving object, making it easier to determine where the detected object is located on the moving object.

[0011] The moving object may be a vehicle, and the object to be detected may be a vehicle lamp provided on the vehicle, thereby making it easier to determine the position of the vehicle lamp on the vehicle.

[0012] The object to be identified may be a fixed object, and the detection target may be configured to appear to be moving to the perimeter monitoring sensor. In this way, the detection target provided on the fixed object appears to be moving, making it easier to identify the fixed object.

[0013] The fixed object may be a traffic signal, and the detected object may be configured to appear to move differently depending on the state of the traffic signal. This allows the traffic signal state to be identified even by a perimeter monitoring sensor that cannot directly detect color information of the traffic signal.

[0014] Another aspect of the present invention is a perimeter monitoring system. This system includes a perimeter monitoring sensor that uses infrared light, and a detected object. The perimeter monitoring sensor may identify the state of an identification object on which the detected object is provided, based on a change in the infrared light emitted from the detected object. This can improve the accuracy of identifying surrounding objects. Furthermore, when there are multiple detected objects provided on a moving object, the orientation of the moving object can be determined based on the relative arrangement of the multiple detected detected objects.

[0015] Any combination of the above components and any conversion of the present invention into a method, device, system, etc. are also valid aspects of the present invention. Effect of the Invention

[0016] According to the present invention, it is possible to improve the accuracy of identifying surrounding objects. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram of a LiDAR unit. [Diagram 2] Figure 2(a) is a schematic diagram illustrating the position of the detectable object when viewed from the front of the vehicle, Figure 2(b) is a schematic diagram illustrating the position of the detectable object when viewed from the rear of the vehicle, and Figure 2(c) is a schematic diagram illustrating the position of the detectable object when viewed from the side of the vehicle. [Diagram 3] 3(a) to 3(d) are schematic diagrams for explaining the shape and movement of the detection object. [Figure 4] 4(a) to 4(d) are schematic diagrams for explaining combinations of mounting positions of a plurality of detection targets. [Diagram 5] 5(a) to 5(d) are schematic diagrams showing an example in which a traffic signal is provided with a plurality of detection targets. [Figure 6] 6(a) and 6(b) are schematic diagrams showing an example in which a plurality of detection objects are provided on a pedestrian traffic light. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, with reference to the drawings, a detailed description will be given of an embodiment of the present invention. In the description of the drawings, the same elements are given the same reference numerals, and duplicated descriptions will be omitted as appropriate. In addition, the configurations described below are examples and do not limit the scope of the present invention in any way. In the following, a LiDAR will be described as an example of a perimeter monitoring sensor that uses infrared light.

[0019] Sensors such as LiDAR use information on the shape of the point cloud and its movement over time to detect and identify objects. Specifically, LiDAR provides information on the detection of surrounding objects, the type of object, the distance to the object, and the location of the object. However, when objects are far away or small, the number of points in the cloud decreases or points are missing, which may reduce the accuracy of object identification.

[0020] Therefore, the inventors of the present application have come up with the idea of ​​providing an object to be discriminated with a detectable object from which characteristic information different from information such as a point cloud obtained from the entire object can be obtained. Specifically, the inventors have come up with the idea that by providing detectable objects such as reflectors that reflect infrared light or light emitters that emit infrared light to objects to be identified such as vehicles and traffic signals, and adding characteristic information obtained from these detectable objects, it is possible to improve the discrimination accuracy of objects to be identified.

[0021] (LiDAR unit) 1 is a schematic diagram of a LiDAR unit. The LiDAR unit 10 includes a housing 12, a transmission part 14, and a LiDAR 16. The transmission part 14 is, for example, an infrared transmission film.

[0022] The LiDAR unit 10 has a LiDAR 16 in a housing 12. The LiDAR 16 is configured to acquire information about the surroundings of the vehicle. The LiDAR 16 is a sensor that generally emits infrared light, which is invisible light, forward and acquires information about the distance to an object, the shape of the object, the material of the object, and the like, based on the emitted light and the returned light. The LiDAR 16 has a light-emitting element 18 that emits light toward the surroundings of the vehicle (forward of the vehicle) and a light-receiving element 20 that receives light incident from the outside.

[0023] (Position of object to be detected) The detected object according to this embodiment is provided on an object to be identified. The detected object according to this embodiment is a moving object that is a movable object, specifically, a vehicle. The detected object is configured so that the detected object appears to move relative to the object to be identified to a periphery monitoring sensor that uses infrared light. FIG. 2(a) is a schematic diagram illustrating the position of the detected object in a front view of the vehicle, FIG. 2(b) is a schematic diagram illustrating the position of the detected object in a rear view of the vehicle, and FIG. 2(c) is a schematic diagram illustrating the position of the detected object in a side view of the vehicle.

[0024] The R1 position shown in Fig. 2(a), which is an example of an installation example of the detection object, is inside the right headlamp 22R. Similarly, the L1 position shown in Fig. 2(a) is inside the left headlamp 22L. A lamp such as a headlamp has a transparent cover and an outer lens that can emit visible light including infrared light to the outside. Therefore, the detection object is protected from the environment compared to a case where the detection object is installed outside the vehicle (for example, on the exterior).

[0025] In addition, the interval L [m] between the right headlamp 22R and the left headlamp 22L may be set to a constant value regardless of the vehicle. This allows the LiDAR unit 10 of another vehicle to detect multiple objects whose movements are different from the movement of the vehicle from the information of the surrounding objects, and when the interval between the objects corresponds to L, the object can be identified as a vehicle.

[0026] 2(a) corresponds to the rear side of the rearview mirror inside the vehicle, and is a position where infrared light can be irradiated to the detection object through the front window and emitted from the detection object to the outside of the vehicle. Therefore, the detection object is protected from the environment compared to a case where the detection object is provided outside the vehicle (for example, on the exterior).

[0027] Next, the location of the detected object when viewed from the rear of the vehicle will be described. Position R1' shown in Fig. 2(b) is inside the right tail lamp 24R. Similarly, position L1' shown in Fig. 2(b) is inside the left tail lamp 24L. In addition, the distance L [m] between the right tail lamp 24R and the left tail lamp 24L is preferably set to a constant value regardless of the vehicle.

[0028] As a result, when the LiDAR unit 10 of another vehicle detects multiple objects whose movement is different from that of the vehicle from information about surrounding objects, and the distance between the objects corresponds to L, the object can be identified as a vehicle.

[0029] 2(b) corresponds to the inside of the upper part of the rear window of the vehicle, and is a position where infrared light can be irradiated to the detection object through the rear window and emitted from the detection object to the outside of the vehicle. Therefore, the detection object is protected from the environment compared to a case where the detection object is provided outside the vehicle (for example, on the exterior).

[0030] 2(a) to 2(c) are examples of candidate mounting positions for the object to be detected in a vehicle. The positions A1 to A13 are selected from locations that are easy to identify as a vehicle, such as the roof, bumper, license plate, door handle, roof rail, etc.

[0031] (Movement of detected object) 3(a) to 3(d) are schematic diagrams for explaining the shape and movement of the detection target. The shape of the detection target may be a polygon such as a triangle or a square, a circle, an ellipse, a rectangular parallelepiped, or a curved surface, and may have a large reflective or self-luminous area and move in a characteristic manner as a point cloud detected by the LiDAR 16. The detection target may also be a reflector, a part in which a reflector is embedded, a unit in which a reflector is arrayed, or a reflecting surface (such as a mirror). The detection target may also be a self-luminous object, a part in which a self-luminous object is embedded, a unit in which a reflector is arrayed, or a self-luminous surface (a light guide or an optical fiber surface).

[0032] The detected object 26a shown in Fig. 3(a) is a rectangular parallelepiped light-emitting or reflecting object, and moves relative to the vehicle. More specifically, the detected object 26a oscillates at a specific period around the Y axis in the vertical direction of the vehicle. Therefore, when infrared light emitted from the LiDAR 16 of another vehicle is irradiated onto the vehicle on which the detected object 26a is provided, information on the detected object 26a that appears to move differently from the vehicle's movement is obtained in addition to point cloud information on the entire object corresponding to the vehicle.

[0033] More specifically, in addition to the point cloud information of the entire vehicle obtained by the LiDAR unit 10 of the other vehicle, dynamic information obtained by the oscillation of the detected object 26a different from the vehicle's movement is obtained. As a result, point cloud information of a (characteristic) movement different from the vehicle's movement is obtained in a part of the overall vehicle outline obtained from the point cloud. Then, based on the position of the point cloud of the characteristic movement on the vehicle and the characteristic movement, it is possible to determine not only that the object is a vehicle, but also which direction the vehicle is facing. For example, when the movement of the detected object 26a corresponds to the movement of the detected object provided at the position R1 corresponding to the right headlamp 22R, it can be estimated that the vehicle is an oncoming vehicle.

[0034] As another example of the movement of the detected object, as shown in Fig. 3(b), the detected object 26a may reciprocate at a specific period along the X-axis in the vehicle width direction. As shown in Fig. 3(c), the circular detected object 26b may reciprocate at a specific period along the Y-axis in the vehicle up-down direction. As shown in Fig. 3(d), the square detected object 26c may reciprocate at a specific period along the Z-axis in the vehicle front-rear direction.

[0035] In this manner, the detectable objects 26a to 26c according to the present embodiment are configured so that the reflection position or reflection direction of the area that reflects infrared light changes, which makes it easier for the detectable object to be seen as moving in a manner different from the movement of the vehicle, making it easier to determine where the detectable object is located on the vehicle.

[0036] Also, the detected object itself may not move relative to the vehicle, and the light-emitting state of the detected object may be changed so that the detected object appears to move relative to the vehicle. More specifically, the detected object itself may not move, and the light-emitting surface of the detected object may flicker or the light-emitting area may change stepwise so that the detected object appears to move differently from the movement of the vehicle. For example, the light-emitting area of ​​the light guide may be changed periodically. This makes it easier to determine where the detected object is located on the vehicle, even if the detected object itself does not move. Also, the reflection or flashing of infrared light does not flicker or obstruct the view of the driver or pedestrian.

[0037] In addition, by changing the movement of the detection object for each mounting position on the vehicle, the object identification accuracy can be further improved. Fig. 4(a) to Fig. 4(d) are schematic diagrams for explaining combinations of mounting positions of multiple detection objects. As shown in Fig. 4(a), by mounting detection objects at positions R1 and L1 on the vehicle, characteristic information that allows the left and right headlamps of the vehicle to be recognized can be added to the point cloud information of the object detected by the LiDAR 16. In addition, as shown in Fig. 4(b), by providing a detection object at position f1 in addition to positions R1 and L1, the object identification accuracy can be further improved.

[0038] FIG. 4(c) shows a case where a detected object is mounted at position L1', position R1', and position A7 shown in FIG. 2(b). When a point cloud showing a characteristic movement is present at position L1', position R1', and position A7 among the point cloud showing the outline of the object, the LiDAR unit 10 of the other vehicle identifies the detected object as a vehicle. In addition, when the movement of the detected object mounted at position L1' corresponds to the left tail lamp 24L and the movement of the detected object mounted at position R1' corresponds to the right tail lamp 24R, it can also be identified that the identified vehicle is a leading vehicle (a vehicle traveling ahead in the own lane) as seen from the other vehicle.

[0039] Fig. 4(d) shows a case where a detection target is mounted at position A8, position A9, position A10, and position A13 shown in Fig. 2(c). If a point cloud showing a characteristic movement is present at position A8, position A9, position A10, and position A13 among the point clouds showing the outline of the object, the LiDAR unit 10 of the other vehicle identifies the detected object as a vehicle seen from the side.

[0040] In this way, by providing multiple detectable objects at different locations on the vehicle and assigning each detectable object a different movement corresponding to its mounting position, the orientation of the vehicle can be determined based on the relative positioning of the multiple detectable objects.

[0041] As described above, the detection object according to the present embodiment is configured so that the detection object appears to move relative to the vehicle (identification target) to the LiDAR unit 10 that uses infrared light. According to this aspect, by using information based on the observed movement of the detection object, the vehicle identification accuracy can be improved.

[0042] In addition, the detected object according to the present embodiment is configured to appear to move differently from the vehicle to the LiDAR unit 10 that uses infrared light. This allows, for example, characteristic information about where the detected object is located on the vehicle to be obtained.

[0043] (Traffic signal identification) The object to be identified is not limited to a moving object such as a vehicle, but may be a fixed object that is an object fixed at a predetermined position. Therefore, the object to be detected according to the present embodiment may be provided not only to a moving object such as a vehicle, but also to a fixed object such as a traffic signal. Figures 5(a) to 5(d) are schematic diagrams showing an example in which a plurality of objects to be detected are provided on a traffic signal.

[0044] A traffic light 30 for vehicles shown in FIG. 5(a), which is a kind of traffic light, has detectable objects at a position R1 above a green signal light, a position C1 above a yellow signal light, and a position L1 above a red signal light. These detectable objects are configured so that they appear to move relative to the traffic light to a surrounding monitoring sensor that uses infrared light. More specifically, these detectable objects are configured so that they appear to move to a LiDAR unit 10 equipped in a vehicle. In this way, the three detectable objects that are in a predetermined positional relationship with the three colored signal lights of the traffic light 30 for vehicles appear to move, making it easier to identify the traffic light 30 for vehicles. In addition, by making the movement of the detectable object above the lighted color of the three detectable objects different from the movement of the other two detectable objects, it is possible to determine which colored signal light of the traffic light 30 for vehicles is on.

[0045] The vehicular traffic light 32 shown in Fig. 5(b) is the same as the vehicular traffic light 30 shown in Fig. 5(a), except that the detectable object corresponding to the yellow signal light among the three detectable objects in the vehicular traffic light 30 shown in Fig. 5(a) is provided at position C1' below the yellow signal light. As a result, the three detectable objects are arranged at the vertices of a triangle, making it easier to recognize a point cloud that exhibits a characteristic movement among the point cloud that indicates the general shape of the vehicular traffic light. In other words, even the LiDAR unit 10, which has difficulty directly detecting color information of a traffic light, can identify the lighting state of the traffic light.

[0046] In the vehicular traffic signal 34 shown in Fig. 5(c), detectable objects corresponding to the three colored signal lights are provided at three positions R1, C1, and L1 on the support pole. The functions of the detectable objects are the same as those of the vehicular traffic signal 30. The vehicular traffic signal 36 shown in Fig. 5(d) is the same as the vehicular traffic signal 30, except that, of the three detectable objects in the vehicular traffic signal 34 shown in Fig. 5(c), the detectable object corresponding to the yellow signal light is provided at position C1' on the right of the support pole.

[0047] 6(a) and 6(b) are schematic diagrams showing an example in which a plurality of detection objects are provided on a pedestrian traffic light.

[0048] A pedestrian traffic light 38 shown in FIG. 6(a), which is a type of traffic light, has detectable objects at position A1 above a red signal light and position A2 below a blue signal light. These detectable objects are configured to appear to move to the LiDAR unit 10 equipped in the vehicle. In this way, the two detectable objects that are in a predetermined positional relationship with respect to the two colored signal lights of the pedestrian traffic light 38 appear to move, making it easier to identify the pedestrian traffic light 38. In addition, by making the movement of the detectable object above or below the signal light of the color that is lit or flashing different from the movement of the other detectable object, it is possible to determine which colored signal light of the pedestrian traffic light 38 is lit.

[0049] 6(b), a pedestrian traffic light 40 has two detectable objects corresponding to two colors of signal lights at two positions A1 and A2 on the support pole. The functions of the detectable objects are the same as those of the vehicle traffic light 30.

[0050] The periphery monitoring system according to the present embodiment includes a LiDAR unit 10 that uses infrared light and a detected object. The LiDAR unit 10 identifies the state of the object on which the detected object is located based on changes in the infrared light emitted from the detected object. This improves the accuracy of identifying surrounding objects. In addition, when there are multiple detected objects on a vehicle, the orientation of the vehicle can be determined based on the relative arrangement of the multiple detected detected objects.

[0051] Although the present invention has been described above with reference to the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and suitable combinations or substitutions of the configurations of the embodiments are also included in the present invention. In addition, it is possible to suitably rearrange the combinations and processing order in the embodiments based on the knowledge of a person skilled in the art, and to make modifications such as various design changes to the embodiments, and such modified embodiments are also included in the scope of the present invention.

[0052] In the above embodiment, the examples where the object to be identified is a vehicle or a traffic signal have been mainly described. The object to be identified is not limited to the object described in the above embodiment, and may be various objects including moving objects and fixed objects. The object to be identified may be, for example, a device (e.g., a forklift) that performs various operations (e.g., movement) in a factory, a worker (e.g., work clothes worn by a worker), or a fixed object (e.g., a traffic light) arranged in a factory. It is also possible to provide a detection object to these objects to be identified, and to monitor the state (e.g., movement) of each object to be identified by using information based on the observed movement of the detection object. [Industrial Applicability]

[0053] The present invention can be used in a system for monitoring an object to be detected and its surroundings. [Explanation of symbols]

[0054] 10 LiDAR unit, 12 housing, 14 transmissive portion, 16 LiDAR, 18 light emitting element, 20 light receiving element, 22R right side headlamp, 22L left side headlamp, 24R right side taillamp, 26a, 26b, 26c detected object, 24L left side taillamp, 30 vehicle traffic light, 38 pedestrian traffic light.

Claims

1. a first detection object and a second detection object provided on the object to be identified; A sensor unit including a perimeter monitoring sensor that uses infrared light, the first detection object and the second detection object each have an area that emits or reflects infrared light, and the area is configured to be displaced relative to the object to be identified; a distance between the first and second detection objects corresponds to a type of the object to be identified; A perimeter monitoring system characterized in that the sensor unit identifies the type of the identification object based on the change in the area of ​​each of the first and second detectable objects relative to the identification object, each detected by the perimeter monitoring sensor, and the distance between the first and second detectable objects.

2. the object to be identified is a moving object, The first detection object is configured so that the first detection object appears to have a movement different from the movement of the moving object to the perimeter monitoring sensor, 2. The perimeter monitoring system according to claim 1, wherein the second detected object is configured so that its movement appears to the perimeter monitoring sensor to be different from the movement of the moving object.

3. The perimeter monitoring system of claim 2, characterized in that the first detectable object and the second detectable object are each configured so that the reflection position or reflection direction of the area reflecting infrared light can be changed.

4. The perimeter monitoring system as described in Claim 2, characterized in that the first detectable object and the second detectable object are each configured to change the area from which infrared light is emitted.

5. the moving object is a vehicle, 5. The surroundings monitoring system according to claim 2, wherein the first detectable object and the second detectable object are provided in vehicle lamps of the vehicle.

6. The object to be identified is a fixed object, The first detected object is configured so that the first detected object appears to be moving to the perimeter monitoring sensor, 2. The perimeter monitoring system according to claim 1, wherein the second object is configured to appear to be moving to the perimeter monitoring sensor.

7. the fixed object is a traffic signal, 7. The perimeter monitoring system according to claim 6, wherein the first detectable object and the second detectable object are configured so that their movements appear different depending on the illumination state of the traffic signal.

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