JP7471927B2 - Obstacle detection device, vehicle, obstacle detection system, and obstacle detection method - Google Patents

Description

The present invention relates to an obstacle detection device, a vehicle, an obstacle detection system, and an obstacle detection method.

There are obstacle detection devices that measure the three-dimensional distance around a vehicle such as an automobile, and based on that measurement data, detect objects around the vehicle, as well as obstacles such as grooves and holes in the road surface.

For example, there is a known obstacle detection device for a vehicle that identifies obstacles on a road based on images taken by an infrared camera that captures the area in front of the vehicle and images taken by a stereo camera that captures the area in front of the vehicle (see, for example, Patent Document 1).

JP 2013-020543 A

When applying such an obstacle detection device to autonomous driving, etc., there is a demand for faster processing speed (e.g. frame rate) for detecting obstacles in order to detect obstacles responsively while driving.

In order to increase the processing speed for detecting obstacles, it is possible to consider a method of reducing the amount of data to be processed by, for example, reducing the number of measurement points to be measured. However, in this case, there is a problem that the accuracy of detecting obstacles, particularly obstacles on the road surface (e.g., grooves, holes, etc.), deteriorates.

One embodiment of the present invention has been made in consideration of the above problems, and in an obstacle detection device that detects obstacles in front of a vehicle, the processing speed for detecting obstacles is increased while suppressing deterioration in the detection accuracy of obstacles on the road surface.

In order to solve the above problems, an obstacle detection device according to one embodiment of the present invention is an obstacle detection device that detects an obstacle based on the distance to a plurality of measurement points in front of a vehicle , and includes a distance measurement unit that measures the distance to the plurality of measurement points, and a measurement point determination unit that reduces the number of the plurality of measurement points to reduce the amount of data to be processed, and when reducing the amount of data to be processed, the measurement point determination unit reduces the number of measurement points among the plurality of measurement points that correspond to the traveling direction of the vehicle while maintaining the number of measurement points that correspond to the traveling direction.

According to one embodiment of the present invention, in an obstacle detection device that detects obstacles in front of a vehicle, it is possible to increase the processing speed for detecting obstacles while suppressing deterioration in the detection accuracy of obstacles on the road surface.

FIG. 1 is a diagram illustrating an example of a system configuration of an obstacle detection system according to an embodiment. 1 is a diagram for explaining a resolution in a traveling direction of a vehicle according to an embodiment; FIG. 2 is a diagram illustrating an example of a hardware configuration of a computer according to an embodiment. 1 is a diagram illustrating an example of a functional configuration of an obstacle detection device according to a first embodiment; FIG. 4 is a diagram showing an image of a plurality of measurement points according to the first embodiment. FIG. 11 is a diagram showing an image of a plurality of measurement points according to the second embodiment. FIG. 13 is a diagram illustrating an example of a functional configuration of an obstacle detection device according to a third embodiment. 13 is a flowchart (1) showing an example of a process of an obstacle detection device according to a third embodiment. FIG. 13 is a diagram showing an image of a plurality of measurement points according to the third embodiment. 13 is a flowchart (2) showing an example of a process of the obstacle detection device according to the third embodiment.

The following describes an embodiment of the present invention with reference to the attached drawings.

<System Configuration>
1 is a diagram showing an example of a system configuration of an obstacle detection system according to an embodiment. The obstacle detection system 1 is a system that detects an obstacle in front of a vehicle 10 such as an automobile, and includes an obstacle detection device 100 mounted on the vehicle 10, a distance sensor 110, and the like.

The distance sensor 110 is a sensor such as a LIDAR (Light Detection and Ranging, or Laser Imaging Detection and Ranging), a stereo camera, or a millimeter wave radar, used to measure the distance to multiple measurement points ahead of the vehicle 10. As shown in FIG. 1, the distance sensor 110 is provided facing the traveling direction of the vehicle 10, and a measurement axis (measurement direction) 111 is set so that the distance to an object within a predetermined range 112 including the road surface 11 ahead can be measured.

In this embodiment, the distance sensor 110 may be a sensor of any type that can measure the distance to multiple measurement points within a predetermined range 112 in front of the vehicle 10.

The obstacle detection device 100 is mounted on the vehicle 10 and is an ECU (Electric Control Unit) having a computer configuration, or an information processing device, and controls the distance sensor 110 to measure the distance (three-dimensional distance) to multiple measurement points ahead of the vehicle 10. The obstacle detection device 100 also detects obstacles ahead (e.g., other vehicles, grooves, holes, fallen objects, etc. on the road surface 11) based on the measurement results of the distances to the multiple measurement points.

The method for detecting an obstacle by the obstacle detection device 100 may be any method that detects an obstacle based on the results of measuring the distance to multiple measurement points in front of the vehicle 10.

When applying such an obstacle detection system 1 to autonomous driving or the like, there is a demand for increasing the processing speed (e.g., frame rate, etc.) for detecting obstacles in order to quickly detect obstacles while driving.

One method for speeding up the processing speed for detecting obstacles is to reduce the number of measurement points to be measured (e.g., thinning out) and thereby reduce the amount of data to be processed. However, this poses the problem that the accuracy of detecting obstacles, particularly obstacles on the road surface 11 (e.g., grooves, holes, fallen objects, etc.), deteriorates.

FIG. 2 is a diagram for explaining the resolution in the traveling direction of the vehicle according to one embodiment.
The resolution of multiple measurement points 201 corresponding to the direction of travel of the vehicle 10 on the road surface 11 is represented, for example, by the distance d1 between adjacent measurement points 201, as shown in Figure 2 (A), and the greater the distance from the vehicle 10, the longer the distance d1 (height h x tan θ).

Therefore, for example, as shown in FIG. 2(B), if the number of measurement points is reduced by thinning out the multiple measurement points 201 on the road surface 11 corresponding to the traveling direction of the vehicle 10, there is a problem that the distance d2 between the measurement points 201 becomes too long. For example, in the example of FIG. 2(B), it becomes impossible to detect obstacles 202 such as depressions or holes between the measurement points 201.

In addition, there are also known downsampling methods (e.g., VoxelGridFilter) that maintain resolution instead of simple thinning, but these methods impose a higher processing load than thinning, and therefore cannot be expected to speed up the processing speed for obstacle detection.

The obstacle detection device 100 according to this embodiment has a function of reducing the number of measurement points among the multiple measurement points ahead of the vehicle 10 while maintaining the number of measurement points that correspond to the traveling direction of the vehicle 10 on the road surface 11.

As an example, the obstacle detection device 100 reduces the number of measurement points that correspond to a direction intersecting the traveling direction of the vehicle 10 while maintaining the number of measurement points that correspond to the traveling direction of the vehicle 10 among the multiple measurement points in front of the vehicle 10.

With these functions, the obstacle detection device 100 according to this embodiment can increase the processing speed for detecting obstacles while suppressing deterioration in the detection accuracy of obstacles on the road surface 11.

<Hardware Configuration>
The obstacle detection device 100 has, for example, the hardware configuration of a computer 300 as shown in Fig. 3. Note that the obstacle detection device 100 may further have, for example, a graphic processing unit (GPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), etc. in addition to the configuration of the computer 300 shown in Fig. 3.

Figure 3 is a diagram showing an example of the hardware configuration of a computer according to an embodiment. The computer 300 has, for example, a CPU (Central Processing Unit) 301, memory 302, a storage device 303, a communication I/F (Interface) 304, an external connection I/F 305, an input device 306, an output device 307, and a bus 308.

The CPU 301 is an arithmetic device (processor) that executes each function of the computer 300 by executing programs stored in, for example, the storage device 303, memory 302, etc. The memory 302 includes, for example, a RAM (Random Access Memory), which is a volatile memory used as a work area for the CPU 301, and a ROM (Read Only Memory), which is a non-volatile memory that stores programs for starting up the computer 300, etc. The storage device 303 is, for example, a large-capacity storage device that stores an OS (Operating System), application programs, various data, etc., and is realized by, for example, an HDD (Hard Disk Drive), SSD (Solid State Drive), etc.

The communication I/F 304 is an interface for communicating with an external device. The communication I/F 304 is connected to, for example, an in-vehicle network, and communicates with other ECUs, sensors, information processing devices, etc. mounted on the vehicle 10. The external connection I/F 305 is an interface for connecting an external device, such as the distance sensor 110, to the computer 300. Note that the computer 300 may communicate with the distance sensor 110 via the communication I/F 304.

The input device 306 is an input device (e.g., a keyboard, a touch panel, a sensor, an operation button, etc.) that accepts input from the outside. The output device 307 is an output device (e.g., a display, a speaker, an indicator lamp, etc.) that outputs to the outside. Note that the input device 306 and the output device 307 may be an integrated display input device (e.g., a touch panel display, etc.). The bus 308 is commonly connected to each of the above components, and transmits, for example, address signals, data signals, and various control signals.

[First embodiment]
Next, the functional configuration of the obstacle detection device 100 according to the first embodiment will be described.

<Functional configuration>
Fig. 4 is a diagram showing an example of the functional configuration of the obstacle detection device according to the first embodiment. The obstacle detection device 100 realizes a distance measurement unit 401, a measurement point determination unit 402, an obstacle detection unit 403, and the like, for example, by executing a predetermined program in the CPU 301 shown in Fig. 3.

The distance measurement unit 401 uses the distance sensor 110 to measure the distance to multiple measurement points in front of the vehicle 10. For example, if the distance sensor 110 is a LIDAR, the distance measurement unit 401 uses the distance sensor 110 to sequentially irradiate multiple measurement points (multiple directions) with laser light and measures the distance to the multiple measurement points based on the time it takes for the reflected light to return. Also, if the distance sensor 110 is a camera (stereo camera or monocular camera), the distance measurement unit 401 acquires distance information to the multiple measurement points from a depth image (distance image) created based on the camera image.

The measurement point determination unit 402 determines a number of measurement points at which the distance measurement unit 401 measures distances. When determining the multiple points, the measurement point determination unit 402 has a function of reducing the number of measurement points to be measured and reducing the amount of data to be processed in order to increase the processing speed for detecting obstacles. For example, the measurement point determination unit 402 determines the multiple measurement points such that the resolution of the measurement points in a direction intersecting (e.g. perpendicular to) the traveling direction of the vehicle 10 is lower than the resolution of the measurement points corresponding to the traveling direction of the vehicle 10.

Figure 5 is a diagram showing an image of multiple measurement points according to the first embodiment. Figure 5 (A) is the same diagram as Figure 2 (A). As described above, the resolution of the measurement points 201 corresponding to the traveling direction of the vehicle 10 on the road surface 11 is represented by the distance d1 between adjacent measurement points 201, and the greater the distance from the vehicle 10, the longer the distance d1. Therefore, if the number of measurement points 201 corresponding to the traveling direction of the vehicle 10 on the road surface 11 is reduced, there is a problem that the detection accuracy of obstacles on the road surface 11 deteriorates, as described in Figure 2 (B), for example.

Therefore, the measurement point determination unit 402, for example, reduces the number of measurement points corresponding to a direction intersecting the traveling direction of the vehicle 10 while maintaining the number of measurement points 201 corresponding to the traveling direction of the vehicle 10 on the road surface 11.

Figure 5 (B) shows an image of the distance sensor 110 and the measurement range 503 of the distance sensor 110 shown in Figure 5 (A) when viewed from above. As shown in Figure 5 (B), the resolution of the measurement points 504 corresponding to the direction intersecting (e.g. perpendicular) with the traveling direction of the vehicle 10 is represented by the distance d3 between adjacent measurement points 504. The measurement point determination unit 402, for example, reduces (e.g., thins out) the number of the multiple measurement points 504 in the direction 502 perpendicular to the traveling direction 501 while maintaining the number of multiple measurement points 201 corresponding to the traveling direction 501 of the vehicle 10. In this way, the measurement point determination unit 402 can reduce the number of multiple measurement points measured by the distance measurement unit 401 while suppressing deterioration of the detection accuracy of obstacles on the road surface 11.

Figure 5 (C) shows an example of multiple measurement points 511 when the distance measurement unit 401 acquires the distance to multiple measurement points using a depth image 510 created based on a camera image. In Figure 5 (C), the vertical direction of the depth image 510 corresponds to the traveling direction of the vehicle 10, and the horizontal direction corresponds to a direction intersecting the traveling direction of the vehicle 10. In the example of Figure 5 (C), the distance Δx between the horizontal measurement points 511 is set longer than the distance Δy between the vertical measurement points 511 corresponding to the traveling direction of the vehicle 10.

In this way, the measurement point determination unit 402 according to the first embodiment determines a number of measurement points 511 so that the resolution of the measurement points 511 corresponding to the direction intersecting the traveling direction of the vehicle 10 is lower than the resolution of the measurement points 511 corresponding to the traveling direction of the vehicle 10.

Note that the number of measurement points 511 shown in Figures 5(A) to (C) is an example for explanation purposes, and in reality, many more measurement points 511 (e.g., tens to hundreds of points in the vertical direction and tens to hundreds of points in the horizontal direction) are used.

Now, returning to FIG. 4, we will continue to explain the functional configuration of the obstacle detection device 100.

The obstacle detection unit 403 detects obstacles (e.g., other vehicles, grooves, holes, fallen objects, etc. on the road surface 11) ahead of the vehicle 10 based on the distances to the multiple measurement points 511 measured by the distance measurement unit 401. Note that in this embodiment, the method of detecting obstacles is not particularly limited, but for example, the obstacle detection unit 403 may detect obstacles by calculating the three-dimensional coordinates of the multiple measurement points 511 and estimating the shapes of objects, unevenness, etc. on the road surface 11 based on the three-dimensional coordinates.

As described above, the measurement point determination unit 402 according to the first embodiment determines a number of measurement points such that the resolution of the measurement point 504 corresponding to the direction intersecting the traveling direction is lower than the resolution of the measurement point 201 corresponding to the traveling direction.

When reducing the number of multiple measurement points, the measurement point determination unit 402 preferably reduces the number of measurement points 504 corresponding to a direction perpendicular to the traveling direction while maintaining the number of measurement points 201 corresponding to the traveling direction of the vehicle 10.

Therefore, according to the first embodiment, in the obstacle detection device 100 that detects obstacles in front of the vehicle 10, it is possible to increase the processing speed for detecting obstacles while suppressing deterioration in the detection accuracy of obstacles on the road surface 11.

Second Embodiment
5 is an example of a method for determining a plurality of measurement points 511 according to the first embodiment, the distance measurement unit 401 measures distances from the plurality of measurement points. In the second embodiment, another example of a method for determining a plurality of measurement points, the distance measurement unit 401 measures distances from the plurality of measurement points will be described.

The functional configuration of the obstacle detection device 100 according to the second embodiment may be the same as the functional configuration of the obstacle detection device 100 according to the first embodiment shown in FIG. 4. However, the measurement point determination unit 402 according to the second embodiment determines the multiple measurement points such that the resolution of the measurement points on the road surface 11 and other measurement points different from the measurement points on the road surface 11 is lower than the resolution of the measurement points on the road surface 11.

Figure 6 is a diagram showing an image of multiple measurement points according to the second embodiment. In Figure 6 (A), as described above, the resolution of the measurement points 201 corresponding to the traveling direction of the vehicle 10 on the road surface 11 is represented by the distance d1 between adjacent measurement points 201, and the distance d1 increases as the distance from the vehicle 10 increases. Therefore, if the number of measurement points 201 corresponding to the traveling direction of the vehicle 10 on the road surface 11 is reduced, there is a problem that the detection accuracy of obstacles on the road surface 11 deteriorates, as described in Figure 2 (B), for example.

Therefore, the measurement point determination unit 402 according to the second embodiment, for example, reduces the number of other measurement points 601 that are different from the measurement points 201 on the road surface 11, while maintaining the number of measurement points 201 on the road surface 11 among the multiple measurement points.

Figure 6 (B) shows an example of multiple measurement points 611, 612 when the distance measurement unit 401 acquires distances to multiple measurement points from a depth image 610 created based on a camera image. In Figure 6 (B), the vertical direction of the depth image 610 corresponds to the traveling direction of the vehicle 10, and the horizontal direction corresponds to a direction intersecting the traveling direction of the vehicle 10. In addition, in the depth image 610, multiple measurement points 612 in an area 614 below a dashed line 613 correspond to the measurement point 201 on the road surface 11 in Figure 6 (A). In addition, in the depth image 610, multiple measurement points 612 in an area 615 above the dashed line 613 correspond to another measurement point 601 different from the measurement point 201 on the road surface 11 in Figure 6 (A).

The position of the dashed dotted line 613 is assumed to be preset, for example, when the vehicle 10 is manufactured, when the distance sensor 110 is attached, or when a calibration operation is performed.

For example, as shown in FIG. 6B, the measurement point determination unit 402 according to the second embodiment arranges multiple measurement points 611 in the region 614 below the dashed-dotted line 613 at intervals of Δx1 in the horizontal direction and Δy1 in the vertical direction. On the other hand, in the region 615 above the dashed-dotted line 613, the measurement point determination unit 402 arranges multiple measurement points 612 at intervals of Δx1 in the horizontal direction and Δy2 (Δy2>Δy1) in the vertical direction by thinning out the multiple measurement points 612 in the horizontal direction so that they are on every other row.

As a result, the measurement point determination unit 402 according to the second embodiment can reduce the number of other measurement points 612 while maintaining the number of measurement points 611 on the road surface 11.

Note that the method of arranging the multiple measurement points shown in FIG. 6(B) is one example. The measurement point determination unit 402 may thin out the multiple measurement points 612 in the vertical direction in the region 615 above the dashed dotted line 613 so that they are spaced every other row. As a result, for example, as shown in FIG. 6(C), the multiple measurement points 612 may be determined so that they are spaced apart by Δx2 (Δx2>Δx1) in the horizontal direction and Δy2 (Δy2>Δy1) in the vertical direction.

As described above, the measurement point determination unit 402 according to the second embodiment determines a plurality of measurement points such that the resolution of the measurement point 612, which is different from the measurement point on the road surface 11, is lower than the resolution of the measurement point 611 on the road surface 11.

When reducing the number of multiple measurement points, the measurement point determination unit 402 preferably reduces the number of other measurement points 612 among the multiple measurement points while maintaining the number of measurement points 611 on the road surface 11.

Therefore, even in the second embodiment, the obstacle detection device 100 that detects obstacles in front of the vehicle 10 can increase the processing speed for detecting obstacles while suppressing deterioration in the detection accuracy of obstacles on the road surface 11.

[Third embodiment]
When the obstacle detection device 100 is applied to the autonomous driving of the vehicle 10, the processing speed (e.g., frame rate, etc.) for detecting an obstacle needs to be increased as the traveling speed of the vehicle 10 increases. Therefore, in the third embodiment, an example of processing in which the measurement point determination unit 402 determines a plurality of measurement points according to the traveling speed of the vehicle 10 will be described.

<Functional configuration>
Fig. 7 is a diagram showing an example of the functional configuration of the obstacle detection device 100 according to the third embodiment. As shown in Fig. 7, the obstacle detection device 100 according to the third embodiment has a traveling speed acquisition unit 701 in addition to the functional configuration of the obstacle detection device 100 according to the first embodiment shown in Fig. 4. Note that the system configuration of the obstacle detection system 1 according to the third embodiment and the hardware configuration of the obstacle detection device 100 may be similar to those of the first and second embodiments.

The driving speed acquisition unit 701 is realized, for example, by a program executed by the CPU 301 in FIG. 3, and acquires the driving speed of the vehicle 10 from another ECU (e.g., an ECU that controls the driving of the vehicle 10) equipped in the vehicle 10 via the external connection I/F 305.

In addition, the measurement point determination unit 402 according to the third embodiment determines a number of measurement points at which the distance measurement unit 401 measures distances, depending on the traveling speed of the vehicle 10 acquired by the traveling speed acquisition unit 701.

The functions of the other functional components (distance measurement unit 401, obstacle detection unit 403) of the obstacle detection device 100 according to the third embodiment may be the same as those of the first and second embodiments.

<Processing flow>
Next, a process flow of the obstacle detection method according to the third embodiment will be described.

(Obstacle detection device process 1)
Fig. 8 is a flowchart (1) showing an example of the process of the obstacle detection device according to the third embodiment. This process shows an example of the obstacle detection process executed by the obstacle detection device 100. The obstacle detection device 100 detects an obstacle in front of the vehicle 10 by repeatedly executing, for example, the process shown in Fig. 8.

In step S801, the traveling speed acquisition unit 701 of the obstacle detection device 100 acquires the traveling speed of the vehicle 10 from an ECU or the like that controls the traveling of the vehicle 10.

In step S802, the measurement point determination unit 402 of the obstacle detection device 100 determines whether the traveling speed of the vehicle 10 is equal to or greater than a predetermined speed (or exceeds the predetermined speed). Note that the predetermined speed is set in advance to a speed (e.g., about 30 km/h to 80 km/h) that increases the processing speed of the obstacle detection process.

If the traveling speed of the vehicle 10 is equal to or greater than the predetermined speed, the measurement point determination unit 402 shifts the process to step S803. On the other hand, if the traveling speed is less than the predetermined speed, the measurement point determination unit 402 shifts the process to step S804.

When the process proceeds to step S803, the measurement point determination unit 402 reduces the number of multiple measurement points. For example, in the default state, the multiple measurement points 901 at which the distance measurement unit 401 measures distances are equally spaced apart at intervals D in the horizontal direction and at distances D in the vertical direction of the depth image 900, as shown in FIG. 9(A).

When reducing the number of multiple measurement points 901 from this state, the measurement point determination unit 402 may, for example, apply the first embodiment to reduce the number of multiple measurement points 901 as shown in FIG. 9(B). In the example of FIG. 9(B), the measurement point determination unit 402 thins out every other row of measurement points 901 from the state of FIG. 9(A) to double the distance D between measurement points in the horizontal direction to 2D. In this way, the measurement point determination unit 402 may reduce the number of measurement points 901 in the direction perpendicular to the traveling direction of the vehicle 10 (horizontal direction) while maintaining the number of measurement points 901 corresponding to the traveling direction of the vehicle 10 (vertical direction).

Alternatively, the measurement point determination unit 402 may apply, for example, the second embodiment and reduce the number of multiple measurement points 901, for example, as shown in FIG. 9(C). In the example of FIG. 9(C), the measurement point determination unit 402 thins out every other row of measurement points 901b in other areas 903 that are different from the area 902 corresponding to the road surface 11 from the state of FIG. 9(A), and changes the distance between the measurement points 901b in the vertical direction to twice as long, 2D. In this way, the measurement point determination unit 402 may reduce the number of other measurement points 901b while maintaining the number of measurement points 901a in the area 902 corresponding to the road surface 11.

When proceeding to step S803 in FIG. 8, if the number of measurement points 901 has already been reduced, as shown in, for example, FIGS. 9(B) and (C), the measurement point determination unit 402 maintains the current state (reduced state).

When moving from step S802 to step S804 in FIG. 8, the measurement point determination unit 402 stops reducing the number of the multiple measurement points 901. For example, when moving to step S804, if the number of measurement points 901 has already been reduced as shown in FIGS. 9(B) and (C), the measurement point determination unit 402 returns the multiple measurement points 901 to the default state as shown in FIG. 9(A). On the other hand, when moving to step S804, if the number of multiple measurement points 901 is in the default state as shown in FIG. 9(A), the measurement point determination unit 402 maintains the current state (default state).

In step S805, the distance measurement unit 401 of the obstacle detection device 100 measures the distances to the multiple measurement points 901 determined in steps S801 to S804.

In step S806, the obstacle detection unit 403 of the obstacle detection device 100 detects an obstacle in front of the vehicle 10 based on the distances to the multiple measurement points 901 measured by the distance measurement unit 401. Information about the obstacle detected by the obstacle detection unit 403 is output to, for example, an ECU (e.g., an ECU for automatic driving control) provided in the vehicle 10, an information processing device, etc.

By performing the above processing, the obstacle detection device 100 can increase the processing speed for detecting obstacles while suppressing deterioration in the detection accuracy of obstacles on the road surface 11 when the traveling speed of the vehicle 10 reaches or exceeds a predetermined speed.

The processing of the obstacle detection device shown in FIG. 8 is an example. For example, the obstacle detection device 100 may switch the method of reducing the number of the multiple measurement points 901 according to three or more speed ranges. Furthermore, the obstacle detection device 100 may apply a combination of the first embodiment and the second embodiment when reducing the number of the multiple measurement points 901.

(Obstacle detection device processing 2)
Fig. 10 is a flowchart (2) showing an example of the process of the obstacle detection device according to the third embodiment. This process shows another example of the obstacle detection process executed by the obstacle detection device 100. The obstacle detection device 100 detects an obstacle in front of the vehicle 10 by repeatedly executing, for example, the process shown in Fig. 10. Note that a detailed description of the process similar to the process described in Fig. 8 will be omitted here.

In step S1001, the traveling speed acquisition unit 701 of the obstacle detection device 100 acquires the traveling speed of the vehicle 10 from an ECU or the like that controls the traveling of the vehicle 10.

In step S1002, the measurement point determination unit 402 of the obstacle detection device 100 determines whether the traveling speed of the vehicle 10 is equal to or greater than a first speed that has been set in advance (e.g., approximately 20 to 40 km/h).

If the traveling speed of the vehicle 10 is less than the first speed, the measurement point determination unit 402 shifts the process to step S1003. On the other hand, if the traveling speed is equal to or greater than the first speed, the measurement point determination unit 402 shifts the process to step S1004.

When proceeding to step S1003, the measurement point determination unit 402 stops reducing the number of the multiple measurement points 901. For example, when proceeding to step S1003, if the number of measurement points 901 has already been reduced, the measurement point determination unit 402 returns the multiple measurement points 901 to the default state as shown in FIG. 9(A). On the other hand, when proceeding to step S1003, if the number of multiple measurement points 901 is in the default state as shown in FIG. 9(A), the measurement point determination unit 402 maintains the current state (default state).

On the other hand, when the process moves from step S1002 to step S1004, the measurement point determination unit 402 determines whether the traveling speed of the vehicle 10 is equal to or greater than a second speed that has been set in advance (e.g., approximately 60 to 80 km/h).

If the traveling speed of the vehicle 10 is less than the second speed, the measurement point determination unit 402 shifts the process to step S1005. On the other hand, if the traveling speed of the vehicle 10 is equal to or greater than the second speed, the measurement point determination unit 402 shifts the process to step S1006.

When the process proceeds to step S1005, the measurement point determination unit 402 reduces the number of measurement points 901b on the road surface 11 that are different from the measurement point 901a, for example, as described in FIG. 9(C). Note that when the process proceeds to step S1005, if the number of measurement points 901 has already been reduced, for example, as shown in FIG. 9(C), the measurement point determination unit 402 maintains the current state.

On the other hand, when moving from step S1004 to step S1006, the measurement point determination unit 402 reduces the number of multiple measurement points 901, for example, as shown in FIG. 9 (D).

In the example of FIG. 9(D), the measurement point determination unit 402 thins out every other row of measurement points 901b on the road surface 11 that are different from the measurement point 901a from the state of FIG. 9(A), thereby changing the distance between the measurement points 901b in the vertical direction to 2D, which is doubled. Furthermore, the measurement point determination unit 402 thins out every other column of measurement points 901a and measurement points 901b, thereby changing the distance D between the measurement points in the horizontal direction to 2D, which is doubled.

In this way, the measurement point determination unit 402 may combine the first and second embodiments to reduce the number of multiple measurement points 901. Note that in the depth image 900 shown in FIG. 9(D), multiple measurement points 901 are also determined so that the resolution of the measurement point 901 corresponding to the traveling direction of the vehicle 10 on the road surface 11 is lower than the resolution of the other measurement points 901.

In step S1007, the distance measurement unit 401 of the obstacle detection device 100 measures the distances to the multiple measurement points 901 determined in steps S1001 to S1006.

In step S1006, the obstacle detection unit 403 of the obstacle detection device 100 detects an obstacle in front of the vehicle 10 based on the distances to the multiple measurement points 901 measured by the distance measurement unit 401. Information about the obstacle detected by the obstacle detection unit 403 is output to, for example, an ECU (e.g., an ECU for automatic driving control) provided in the vehicle 10, an information processing device, etc.

By performing the above processing, the obstacle detection device 100 can switch between methods for reducing the number of multiple measurement points 901 according to multiple speed ranges while suppressing deterioration in the detection accuracy of obstacles on the road surface 11.

As described above, according to each embodiment of the present invention, in an obstacle detection device 100 that detects obstacles in front of a vehicle 10, it is possible to increase the processing speed for detecting obstacles while suppressing deterioration in the detection accuracy of obstacles on the road surface 11.

The present invention is not limited to the above-described embodiments, and various modifications and variations are possible within the scope of the gist of the invention as described in the claims.

For example, the functional configuration of the obstacle detection device 100 shown in FIG. 4 is one example, and may be separated into a distance measurement device including a distance measurement unit 401 and a measurement point determination unit 402, and an obstacle detection device including an obstacle detection unit 403. In this case, the obstacle detection unit 403 may be included in an ECU that controls autonomous driving. In this way, each functional configuration of the obstacle detection device 100 shown in FIGS. 4 and 7 may be included in one or more devices included in the obstacle detection system 1.

Reference Signs List 1 Obstacle detection system 10 Vehicle 11 Road surface 100 Obstacle detection device 110 Distance sensor 401 Distance measurement unit 402 Measurement point determination unit

Claims (5)

An obstacle detection device that detects an obstacle based on distances to a plurality of measurement points in front of a vehicle,
a distance measurement unit for measuring distances to the plurality of measurement points;
a measurement point determination unit that reduces the number of the plurality of measurement points to reduce the amount of data to be processed ;
having
an obstacle detection device, wherein, when reducing the amount of data to be processed, the measurement point determination unit reduces, among the plurality of measurement points, the number of measurement points corresponding to a direction intersecting the vehicle's traveling direction while maintaining the number of measurement points corresponding to the vehicle's traveling direction . The obstacle detection device according to claim 1 , wherein the measurement point determination unit reduces the number of the plurality of measurement points in accordance with a traveling speed of the vehicle. A vehicle equipped with the obstacle detection device according to claim 1 or 2 . 1. An obstacle detection system that detects an obstacle based on distances to a plurality of measurement points in front of a vehicle, comprising:
a distance measurement unit for measuring distances to the plurality of measurement points;
a measurement point determination unit that reduces the number of the plurality of measurement points to reduce the amount of data to be processed ;
having
an obstacle detection system in which, when reducing the amount of data to be processed, the measurement point determination unit reduces, among the plurality of measurement points, the number of measurement points corresponding to a direction intersecting the vehicle's traveling direction while maintaining the number of measurement points corresponding to the vehicle's traveling direction. 1. A method for detecting an obstacle based on distances to a plurality of measurement points in front of a vehicle, comprising:
A process in which a distance measurement unit measures distances to the plurality of measurement points;
A measurement point determination unit reduces the number of the plurality of measurement points to reduce the amount of data to be processed ;
Including,
an obstacle detection method in which, when reducing the amount of data to be processed, the measurement point determination unit reduces, among the plurality of measurement points, the number of measurement points corresponding to a direction intersecting the vehicle's traveling direction while maintaining the number of measurement points corresponding to the vehicle's traveling direction .

Images