Water depth estimation device and water depth estimation method
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- MITSUBISHI MOTORS CORP
- Filing Date
- 2025-01-24
- Publication Date
- 2026-08-05
AI Technical Summary
【0010】 本発明の少なくとも一実施形態によれば、自車両前方の冠水路の水深を正確に推定することができる。
Smart Images
Figure 2026126714000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a water depth estimation device and a water depth estimation method.
Background Art
[0002] Patent Document 1 discloses an in-vehicle device including: specifying means for specifying whether waterlogging has occurred or a waterlogging point with a high risk of waterlogging; imaging means for imaging a waterlogging point with a camera mounted on the host vehicle when the host vehicle travels through the waterlogging point or in the vicinity thereof; and estimation means for estimating the degree of waterlogging at the waterlogging point based on a waterlogging image which is an image of the waterlogging point taken by the imaging means.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In the in-vehicle device disclosed in Patent Document 1, the height from the ground to the water surface at the waterlogging point cannot be accurately estimated unless a marker indicating the height from the ground is shown in the waterlogging image of the waterlogging point. Therefore, it is not easy to determine whether the host vehicle can travel through the waterlogging point (waterlogged road).
[0005] In view of the above circumstances, at least one embodiment of the present invention aims to provide a water depth estimation device and a water depth estimation method capable of accurately estimating the height (water depth) from the road surface to the water surface of a waterlogged road in front of the host vehicle so that it is easy to determine whether the host vehicle can travel through the waterlogged road in front of the host vehicle.
Means for Solving the Problems
[0006] A water depth estimation device according to at least one embodiment of the present invention is a water depth estimation device that estimates the height from the road surface to the water surface of a flooded road at the driving position of another vehicle traveling on the flooded road in front of the vehicle, comprising: an imaging unit installed on the vehicle to capture images of the area in front of the vehicle; a height calculation unit that, when the image captured by the imaging unit includes another vehicle traveling on the flooded road, calculates the height of the visible portion from the water surface of the flooded road to the roof of the other vehicle based on the image; and the position of the vehicle that captured the image including the other vehicle traveling on the flooded road. The system includes: a distance measuring unit that measures the distance from the vehicle to the position of the other vehicle included in the image; a water depth measuring unit that measures the height of the unseen portion from the road surface to the water surface of the flooded road when the vehicle has traveled the distance; a total height calculation unit that calculates the total height of the other vehicle based on the height of the visible portion calculated based on the image captured at the vehicle's position and the height of the unseen portion; and a water depth calculation unit that calculates the height from the road surface to the water surface of the flooded road at the other vehicle's driving position based on the height of the visible portion and the total height of the other vehicle.
[0007] According to the above configuration, the height from the road surface to the water surface of the flooded road at the location of the other vehicle is calculated based on the height of the visible portion and the total height of the other vehicle. Therefore, it is possible to accurately estimate the height (water depth) from the road surface to the water surface of the flooded road (flooded road in front of the vehicle) at the location of the other vehicle traveling in the flooded road ahead of the vehicle.
[0008] A water depth estimation method according to at least one embodiment of the present invention is a water depth estimation method for estimating the height from the road surface to the water surface of a flooded road at the driving position of another vehicle traveling on the flooded road in front of the vehicle, and includes the steps of: having an imaging unit installed on the vehicle take an image of the area in front of the vehicle; if the image taken by the imaging unit includes the other vehicle traveling on the flooded road, calculating the height of the visible portion from the water surface of the flooded road to the roof of the other vehicle based on the image; measuring the distance from the position of the vehicle that took the image including the other vehicle traveling on the flooded road to the position of the other vehicle included in the image; measuring the height of the invisible portion from the road surface to the water surface of the flooded road when the vehicle has traveled the distance; calculating the total height of the other vehicle based on the height of the visible portion calculated based on the image taken at the position of the vehicle and the height of the invisible portion; and calculating the height from the road surface to the water surface of the flooded road at the driving position of the other vehicle based on the height of the visible portion and the total height of the other vehicle.
[0009] According to the method described above, the height from the road surface to the water surface in the flooded road at the location of the other vehicle is calculated based on the height of the visible portion and the total height of the other vehicle. Therefore, it is possible to accurately estimate the height (water depth) from the road surface to the water surface in the flooded road (flooded road in front of your vehicle) at the location of the other vehicle traveling in the flooded road ahead of your vehicle. [Effects of the Invention]
[0010] According to at least one embodiment of the present invention, the water depth of a flooded road in front of the vehicle can be accurately estimated. [Brief explanation of the drawing]
[0011] [Figure 1] This is a block diagram schematically showing the configuration of the water depth estimation device according to Embodiment 1. [Figure 2-1] This diagram shows your vehicle and other vehicles traveling through a flooded road in front of it. [Figure 2-2]Figure 2-1 is a schematic diagram showing images captured by the imaging unit installed on the vehicle. [Figure 3-1] Figure 2-2 shows the position of the vehicle that captured the image, the distance traveled from the position of the vehicle that took the image to the position of the other vehicle included in the image, and the other vehicle traveling in the flooded road ahead of the vehicle. [Figure 3-2] Figure 3-1 is a schematic diagram showing images captured by the imaging unit installed on the vehicle. [Figure 4] This is a flowchart illustrating the operation of the water depth estimation device according to Embodiment 1. [Figure 5] This is a block diagram schematically showing the configuration of the water depth estimation device according to Embodiment 2. [Figure 6-1] This diagram shows the viewpoint used to capture images of other vehicles traveling through a flooded road. [Figure 6-2] This figure schematically shows other vehicles as captured from the viewpoint shown in Figure 6-1. [Figure 7-1] This diagram shows the viewpoint used to capture images of other vehicles traveling through a flooded road. [Figure 7-2] This diagram schematically shows other vehicles as captured from the viewpoint shown in Figure 7-1. [Figure 8-1] This diagram shows the viewpoint used to capture images of other vehicles traveling through a flooded road. [Figure 8-2] This figure schematically shows other vehicles as captured from the viewpoint shown in Figure 8-1. [Figure 9] This is a flowchart illustrating the operation of the water depth estimation device according to Embodiment 2. [Modes for carrying out the invention]
[0012] Hereinafter, several embodiments of the present invention will be described with reference to the attached drawings. However, the dimensions, materials, shapes, relative arrangements, etc., of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples.
[0013] [Embodiment 1] The water depth estimation device according to Embodiment 1 is a device that estimates the water depth at the running position of another vehicle traveling on a crown waterway in front of the host vehicle. The other vehicle traveling on the crown waterway in front of the host vehicle is, for example, the vehicle immediately in front of the host vehicle.
[0014] [Configuration of the water depth estimation device] FIG. 1 is a block diagram schematically showing the configuration of a water depth estimation device 1A according to Embodiment 1. As shown in FIG. 1, the water depth estimation device 1A according to Embodiment 1 includes an imaging unit 11, a height calculation unit 13, a distance measurement unit 15, a water depth measurement unit 17, an overall height calculation unit 19, and a water depth calculation unit 21. The height calculation unit 13, the overall height calculation unit 19, and the water depth calculation unit 21 are provided in an electronic control unit (ECU (Electronic Control Unit)) 23, and the imaging unit 11, the distance measurement unit 15, and the water depth measurement unit 17 are electrically connected to the electronic control unit 23.
[0015] The imaging unit 11 is installed on the host vehicle so as to image the front of the host vehicle. The imaging unit 11 is, for example, an in-vehicle camera that photographs the front of the host vehicle, and the imaging unit 11 sequentially images the front of the host vehicle. The in-vehicle camera may be a camera that constitutes a drive recorder installed for the purpose of recording situations such as images at the time of an automobile accident, or may be installed separately from the camera that constitutes the drive recorder.
[0016] As shown in FIGS. 2-2 and 3-2, when the image captured by the imaging unit 11 includes another vehicle VC2 traveling on the crown waterway, the height calculation unit 13 calculates the visible height Hvp from the water surface of the crown waterway to the roof of the other vehicle VC2 based on the image including the other vehicle VC2 traveling on the crown waterway. As described above, since the imaging unit 11 sequentially images the front of the host vehicle VC1, the height calculation unit 13 also sequentially calculates the visible height Hvp.
[0017] For example, if an image containing another vehicle VC2 driving on a flooded road includes the license plate (vehicle registration number plate) 25 of the other vehicle VC2, the height calculation unit 13 calculates the height Hvp of the visible portion from the water surface of the flooded road to the roof of the other vehicle VC2, using the size of the license plate 25 of the other vehicle VC2 as a reference (ruler). The reason for using the size of the license plate 25 as a reference is that the size of license plates 25 is regulated in Japan, and its size can be determined simply by identifying whether it is a large vehicle, a regular vehicle, or a light vehicle. Since the height calculation unit 13 calculates the height Hvp of the visible portion, the reference size of the license plate 25 is the height of the other vehicle VC2, that is, the length of the shorter side of the license plate 25. However, if part of the license plate 25 is submerged, the length of the shorter side of the license plate 25 cannot be used as a reference, so the length of the longer side of the license plate 25 may be used as a reference.
[0018] As shown in Figure 2-1, the distance measurement unit 15 measures the distance D from the position P1 of the self-vehicle VC1 (hereinafter referred to as "first position P1"), where an image including another vehicle VC2 traveling on a flooded road has been captured, to the position P2 of the other vehicle VC2 (hereinafter referred to as "second position P2") included in the image. The distance measurement unit 15 is composed of, but is not limited to, a millimeter-wave radar sensor, an optical camera sensor, or a stereo camera that measures the distance (inter-vehicle distance) from the self-vehicle VC1 to the other vehicle VC2. The first position P1 and the second position P2 are based on the position that is the center of the vehicle in the longitudinal direction. However, when a sensor that measures the inter-vehicle distance is used in the distance measurement unit 15, the distance D from the first position P1 to the second position P2 is the value obtained by adding the distance from the sensor to the rear of the other vehicle VC2 to the distance from the sensor to the rear of the self-vehicle VC1. In other words, the distance D from the first position P1 to the second position P2 is the sum of the distance between your vehicle VC1 and the other vehicle VC2 plus the total length of your vehicle VC1.
[0019] As shown in Figure 2-2, when the vehicle VC1 travels a distance D from the first position P1 to the second position P2, the water depth measurement unit 17 measures the height Hip2 of the unseen portion from the road surface to the water surface of the flooded road at the second position P2. Whether or not the vehicle VC1 has traveled the distance D is determined, for example, by the distance traveled calculated based on the wheel speed measured by the wheel speed sensor. The water depth measurement unit 17 calculates the height Hip2 of the unseen portion based on an image captured by a side camera installed on the door mirror, for example, but is not limited to this, and may be composed of, for example, an optical sensor that detects the water surface or a physical sensor such as a float.
[0020] The total height calculation unit 19 calculates the total height HVC2 of the other vehicle VC2 based on the height Hvp2 of the visible portion calculated based on the image taken at the first position P1 and the height Hip2 of the invisible portion from the road surface to the water surface of the flooded road at the second position P2. The height Hvp of the visible portion calculated based on the image taken at the first position P1 is Hvp2 shown in Figure 2-1, and the height Hip of the invisible portion is Hip2 shown in Figure 3-1, and the total height HVC2 of the other vehicle VC2 is calculated as Hvp2 + Hip2.
[0021] The water depth calculation unit 21 calculates the height Hip from the road surface to the water surface of the flooded road at the location where the other vehicle VC2 is traveling, based on the height Hvp of the visible portion calculated by the height calculation unit 13 and the total height HVC2 of the other vehicle VC2 calculated by the total height calculation unit 19. As described above, the imaging unit 11 continuously images the area in front of the vehicle VC1, and the height calculation unit 13 continuously calculates the height Hvp of the visible portion, so the height Hip from the road surface to the water surface of the flooded road at the location where the other vehicle VC2 is traveling is also calculated continuously.
[0022] [Operation of the water depth estimation device] Figure 4 is a flowchart illustrating the operation of the water depth estimation device 1A according to Embodiment 1. As shown in Figure 4, the water depth estimation device 1A according to Embodiment 1 estimates the height Hip from the road surface to the water surface of the flooded road at the driving position of another vehicle VC2 traveling on the flooded road in front of the vehicle VC1.
[0023] In the water depth estimation device 1A according to Embodiment 1, the imaging unit 11 images the area in front of the vehicle VC1 (step S11). If the image captured by the imaging unit 11 includes another vehicle VC2 traveling on the flooded road (step S12: Yes), the height calculation unit 13 calculates the height Hvp of the visible portion from the water surface of the flooded road to the roof of the other vehicle VC2 based on the image including the other vehicle VC2 traveling on the flooded road (step S13). Next, the distance measurement unit 15 measures the distance D from the vehicle VC1 to the other vehicle VC2 (from the first position P1 to the second position P2) (step S14).
[0024] Then, when the vehicle VC1 has traveled a distance D (step S15: Yes), the water depth measurement unit 17 measures the height Hip2 of the unseen portion from the road surface to the water surface of the flooded road (step S16). Next, the total height calculation unit 19 calculates the total height HVC2 of the other vehicle VC2 based on the height Hvp2 of the visible portion calculated at the first position P1 and the height Hip2 of the unseen portion from the road surface to the water surface of the flooded road at the second position P2 (step S17). Then, the water depth calculation unit 21 calculates the unseen height (height from the road surface to the water surface) Hip of the unseen portion from the road surface to the water surface of the flooded road at the driving position of the other vehicle VC2 based on the height Hvp of the visible portion and the total height HVC2 of the other vehicle VC2 (step S18). Since the total height HVC2 of the other vehicle VC2 traveling in the flooded road in front of the own vehicle VC1 has been calculated, the total height calculation unit 19 does not need to calculate the total height HVC2 of the other vehicle VC2 traveling in the flooded road in front of the own vehicle VC1. Instead, the water depth calculation unit 21 calculates the height Hip from the road surface to the water surface at the position where the other vehicle VC2 is traveling in the flooded road in front of the own vehicle VC1, based on the visible height Hvp calculated by the height calculation unit 13 and the total height HVC2 of the other vehicle VC2.
[0025] [Effectiveness of water depth estimation devices] According to the water depth estimation device 1A of Embodiment 1, the height Hip from the road surface to the water surface of the flooded road at the driving position of the other vehicle VC2 is calculated based on the height Hvp of the visible portion and the total height HVC2 of the other vehicle VC2. Therefore, the height (water depth) Hip from the road surface to the water surface of the flooded road (flooded road in front of the vehicle) at the driving position of the other vehicle VC2 traveling in the flooded road in front of the vehicle VC1 can be accurately estimated.
[0026] [Embodiment 2] [Configuration of the water depth estimation device] Figure 5 is a schematic block diagram showing the configuration of the water depth estimation device 1B according to Embodiment 2. As shown in Figure 5, the water depth estimation device 1B according to Embodiment 2 is the same as the water depth estimation device 1A according to Embodiment 1, except that it includes a water depth correction unit 27.
[0027] The water depth correction unit 27 corrects the height Hip (water depth) from the road surface to the water surface of the flooded road at the location of the other vehicle VC2, which is calculated by the water depth calculation unit 21, based on the distortion of the image which includes the other vehicle VC2 traveling in the flooded road in front of the vehicle VC1. The water depth correction unit 27 is provided in the electronic control unit 23, just like the height calculation unit 13, the total height calculation unit 19, and the water depth calculation unit 21.
[0028] It is known that images captured by on-board cameras are distorted depending on the camera angle AG. When the vehicle VC1 is traveling on a flat road surface, as shown in Figure 6-1, the camera angle AG is set to horizontal, minimizing distortion in the image captured by the on-board camera. Therefore, when the vehicle VC1 is traveling on a flat road surface, as shown in Figure 6-2, the image of another vehicle VC2 captured by the on-board camera will also have minimal distortion. On the other hand, when the vehicle VC1 is traveling downhill with the front end sloping downwards, as shown in Figure 7-1, the camera angle AG looks downwards from the horizontal, so the image of the other vehicle VC2 captured by the on-board camera will show a widening of the vehicle width WH as the vehicle height increases, as shown in Figure 7-2. Conversely, when the vehicle VC1 is traveling uphill with the front end sloping upwards, as shown in Figure 8-1, the camera angle AG looks upwards from the horizontal, so the image of the other vehicle VC2 captured by the on-board camera will show a narrowing of the vehicle width WH as the vehicle height increases, as shown in Figure 8-2.
[0029] In the water depth estimation device 1B according to Embodiment 2, the water depth correction unit 27 corrects the height Vip from the road surface of the flooded road to the water surface at the driving position of the other vehicle VC2, which is calculated by the water depth calculation unit 21, based on such image distortion. For example, if the vehicle width WH widens as the vehicle height increases, the water depth correction unit 27 assumes that the vehicle VC1 is driving on a downhill slope with the front sloping downwards, and corrects the height Vip from the road surface of the flooded road to the water surface, which is calculated by the water depth calculation unit 21, so that it is higher. On the other hand, if the vehicle width WH narrows as the vehicle height increases, the camera angle AG looks upwards from the horizontal, and corrects the height Vip from the road surface of the flooded road to the water surface, which is calculated by the water depth calculation unit 21, so that it is assumed that the vehicle VC1 is driving on an uphill slope with the front sloping upwards.
[0030] [Operation of the water depth estimation device] Figure 9 is a flowchart illustrating the operation of the water depth estimation device 1B according to Embodiment 2. As shown in Figure 9, the operation of the water depth estimation device 1B according to Embodiment 2 is the same as the operation of the water depth estimation device 1A according to Embodiment 1, except for the step (step S19) in which the water depth correction unit 27 corrects the height Hvp from the road surface to the water surface of the flooded road at the driving position of the other vehicle VC2, which is calculated by the water depth calculation unit 21.
[0031] In the water depth estimation device 1B according to Embodiment 2, the water depth correction unit 27 corrects the height Hvp from the road surface to the water surface of the flooded road at the travel position of the other vehicle VC2, which is calculated by the water depth calculation unit 21 based on the distortion of the image captured by the imaging unit 11 (step S19).
[0032] [Effectiveness of water depth estimation devices] In the water depth estimation device 1B according to Embodiment 2, the water depth correction unit 27 corrects the height Hvp from the road surface to the water surface of the flooded road at the travel position of the other vehicle VC2, which is calculated by the water depth calculation unit 21 based on the distortion of the image captured by the imaging unit 11. Therefore, the height Hvp from the road surface to the water surface of the flooded road at the travel position of the other vehicle VC2 can be accurately estimated.
[0033] The present invention is not limited to the embodiments described above, and includes modified forms of the embodiments described above, as well as forms that combine these forms as appropriate. [Explanation of Symbols]
[0034] 1A,1B Water depth estimation device 11 Imaging Unit 13 Height calculation unit 15 Distance measurement unit 17. Depth measurement section 19 Total height calculation section 21 Water depth calculation section 23 Electronic Control Unit (ECU) 25 License plate 27 Depth Correction Section VC1 My vehicle VC2 Other vehicles Height of the visible part of Hvp The height of the unseen part of the hip (water depth) P1 1st position P2 2nd position Height of the visible portion calculated based on the image captured at the Hvp2 first position. Height of the unseen portion from the road surface to the water surface in the flooded road at Hip2, second position. HVC2 Other vehicle overall height
Claims
1. A water depth estimation device that estimates the height from the road surface to the water surface of a flooded road at the position of another vehicle traveling in the flooded road ahead of the vehicle, An imaging unit installed on the vehicle to capture images of the area in front of the vehicle, If the image captured by the imaging unit includes other vehicles traveling on the flooded road, the height calculation unit calculates the height of the visible portion from the water surface of the flooded road to the roof of the other vehicles based on the image, A distance measuring unit measures the distance from the position of the vehicle that captured an image including other vehicles traveling on the flooded road to the position of the other vehicles included in the image. When the vehicle has traveled the aforementioned distance, a water depth measuring unit measures the height of the unseen portion from the road surface to the water surface of the flooded road, A total height calculation unit calculates the total height of the other vehicle based on the height of the visible portion and the height of the invisible portion calculated based on an image taken at the position of the vehicle itself, A water depth calculation unit calculates the height from the road surface to the water surface of the flooded road at the location where the other vehicle is traveling, based on the height of the visible portion and the total height of the other vehicle. A water depth estimation device equipped with the following features.
2. The water depth estimation device according to claim 1, wherein, when an image including other vehicles traveling in the flooded road includes the license plates of the other vehicles, the height calculation unit calculates the height of the visible portion based on the size of the license plates of the other vehicles.
3. The water depth estimation device according to claim 1 or 2, further comprising a water depth correction unit that corrects the height from the road surface to the water surface of the flooded road at the location of the other vehicle, based on the distortion of an image that includes other vehicles traveling on the flooded road.
4. A method for estimating water depth, which estimates the height from the road surface to the water surface of a flooded road at the position of another vehicle traveling in the flooded road ahead of one's own vehicle, The steps include: an imaging unit installed on the vehicle taking an image of the area in front of the vehicle; If the image captured by the imaging unit includes other vehicles traveling on the flooded road, the step of calculating the height of the visible portion from the water surface of the flooded road to the roof of the other vehicles based on the image, The steps include measuring the distance from the position of the vehicle that captured an image including other vehicles traveling on the flooded road to the position of the other vehicles included in the image, The steps include: measuring the height of the unseen portion from the road surface to the water surface of the flooded road when the vehicle has traveled the aforementioned distance; A step of calculating the total height of the other vehicle based on the height of the visible portion and the height of the invisible portion calculated based on the image taken at the position of the vehicle itself, A step of calculating the height from the road surface to the water surface of the flooded road at the driving position of the other vehicle, based on the height of the visible portion and the total height of the other vehicle. A method for estimating water depth, including the following.