Road type estimation device and road type estimation method

Abstract

To determine whether a road on which a vehicle is currently traveling is an expressway without using map data.SOLUTION: A processor performs processing of recognizing a target in a periphery of a vehicle on the basis of image data of the periphery of the vehicle. The processor also performs processing of estimating a type of a road on which the vehicle is traveling. In estimation processing, sign data corresponding to a country in which the vehicle is traveling, is extracted, with reference to a database on the basis of the positional data of the vehicle. In the estimation processing, when a road sign is recognized in the periphery of the vehicle in recognition processing, information indicated by the road sign is compared with information owned by a road sign included in the sign data extracted from the database. When these pieces of information match each other, the road on which the vehicle is traveling is estimated to be an automobile road.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an apparatus and method for estimating road type. [Background technology]

[0002] JP 2017-049206 A discloses an expressway determination device that determines whether or not the road on which a vehicle is currently traveling (hereinafter also referred to as the "currently traveling road") is an expressway. This conventional device determines whether or not the road on which a vehicle is currently traveling is an expressway based on the vehicle's current position data, map data, vehicle traveling data, etc., in order to avoid erroneously determining that a newly opened expressway that connects to an existing expressway is an ordinary road. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-049206 A Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned conventional device judges whether or not the vehicle continues to travel on the expressway. In other words, after obtaining a judgment result that the vehicle is on the expressway, the above-mentioned conventional device judges whether the vehicle should continue to travel based on the above-mentioned current position data, etc. However, the above-mentioned publication does not disclose what information was used to make the presence confirmation judgment, which is the premise for the judgment to continue traveling.

[0005] Here, the presence confirmation determination can be performed by combining the current position data and the map data, for example. However, if either the current position data or the map data is missing, it becomes difficult to perform this determination.

[0006] In particular, there are countries like Japan where detailed map data exists and is accumulated daily, but there are other countries where this is not the case. Therefore, in countries where the amount of map data is insufficient, it must be said that the accuracy of the existence confirmation judgment based on the map data is low. Therefore, even when applied to such countries, there is a demand for the development of technology that makes it possible to determine whether the road currently being driven is an expressway or not.

[0007] One object of the present disclosure is to provide a technique capable of determining whether or not the road on which a vehicle is currently traveling is an expressway, without using map data. [Means for solving the problem]

[0008] The first aspect is a device for estimating the type of road on which a vehicle is traveling, and has the following features. The device includes a database, a memory, and a processor. The database stores sign data consisting of a combination of road signs of expressways and information contained in the road signs. The memory stores image data of the surroundings of the vehicle and position data of the vehicle. The processor performs a recognition process for recognizing targets around the vehicle based on the image data, and a process for estimating the type of road on which the vehicle is traveling. The processor, in the estimation process, extracting sign data corresponding to the country in which the vehicle is traveling by referring to the database based on the location data; When a road sign is recognized around the vehicle in the recognition process, information indicated by the recognized road sign is compared with information of the road sign included in the extracted sign data; When the information indicated by the recognized road sign matches the information held by the road sign included in the extracted sign data, it is estimated that the road on which the vehicle is traveling is a highway for motor vehicles only.

[0009] The second aspect has the same features as the first aspect, as follows. The processor, in the estimation process, When the recognized road signs include a plurality of types of road signs, comparing each piece of information indicated by the plurality of types of road signs with each piece of information of the road signs included in the extracted sign data; If the information indicated by the recognized road sign includes at least information that matches the information held by the road sign included in the extracted sign data, it is presumed that the road on which the vehicle is traveling is a highway for motor vehicles only.

[0010] The third aspect has the following further features in the first or second aspect. The information contained in the road signs of the expressway stored in the database includes information on the vehicle speed limit on the expressway, information on the color of the guide signs installed on the expressway, and information on the structure of the dividing lines painted on the expressway.

[0011] The fourth aspect is a method for estimating the type of road on which a vehicle is traveling, and has the following features. The method comprises: acquiring image data of the surroundings of the vehicle and position data of the vehicle; Recognizing objects around the vehicle based on the image data; extracting sign data corresponding to the country in which the vehicle is traveling, using the location data and a database in which sign data consisting of combinations of road signs of motorways and information contained in the road signs is stored; a step of comparing information indicated by the recognized road sign with information of the road sign included in the extracted sign data when a road sign is recognized around the vehicle in the target recognition step; when information indicated by the recognized road sign matches information of a road sign included in the extracted sign data, estimating that the road on which the vehicle is traveling is a motorway; Equipped with.

[0012] The fifth aspect has the following further features in addition to the fourth aspect. When a plurality of types of road signs are recognized around the vehicle in the target recognition step, the comparison step compares each piece of information indicated by the plurality of types of road signs with each piece of information of the road signs included in the extracted sign data; If the information indicated by the recognized road sign includes at least information that matches the information held by the road sign included in the extracted sign data, the estimation step estimates that the road on which the vehicle is traveling is a highway for motor vehicles only.

[0013] The sixth aspect of the present invention is the fourth or fifth aspect further characterized by the following: The information contained in the road signs of the expressway stored in the database includes information on the vehicle speed limit on the expressway, information on the color of the guide signs installed on the expressway, and information on the structure of the dividing lines painted on the expressway. Effect of the Invention

[0014] According to the first or fourth aspect, a process of recognizing objects around a vehicle based on image data of the vehicle and a process of estimating the type of road on which the vehicle is traveling are performed. In this estimation process, information indicated by road signs recognized in the recognition process is compared with information on road signs included in sign data extracted by referring to a database based on position data and corresponding to the country on which the vehicle is traveling. If the former information matches the latter information, it is estimated that the road on which the vehicle is traveling is a motorway. That is, according to the first or fourth aspect, it is possible to determine whether the road on which the vehicle is currently traveling is a motorway without using map data.

[0015] According to the second or fifth aspect, even if the road signs recognized in the recognition process include multiple types of road signs, it is possible to determine whether the road on which the vehicle is currently traveling is a highway for motor vehicles.

[0016] According to the third or sixth aspect, it becomes possible to determine whether or not the road on which a vehicle is currently traveling is an expressway, based on information on the vehicle speed limit on the expressway, information on the color of guide signs installed on the expressway, or information on the structure of the dividing lines painted on the expressway. [Brief description of the drawings]

[0017] [Figure 1] 1 is a block diagram showing an example of the configuration of a road type estimation device according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram illustrating an example of the structure of sign data stored in a sign database. [Diagram 3] 10 is a flowchart illustrating a flow of a road type estimation process performed by an information processing device (processor). [Figure 4] 10 is a flowchart illustrating a flow of a road type estimation process performed by an information processing device (processor). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, a road type estimation device and an estimation method according to an embodiment of the present invention will be described with reference to the drawings. The estimation method according to the embodiment is realized by computer processing performed in the estimation device. In addition, in each drawing, the same or corresponding parts are given the same reference numerals, and the description thereof will be simplified or omitted.

[0019] 1. Example of the configuration of a road type estimation device The estimation device according to the embodiment is mounted on a vehicle such as a two-wheeled vehicle or a four-wheeled vehicle. Fig. 1 is a block diagram showing a configuration example of the estimation device according to the embodiment. In the example shown in Fig. 1, the estimation device 1 includes a GPS (Global Positioning System) sensor 11, a camera 12, a sign database (sign DB) 13, and an information processing device 14.

[0020] The GPS sensor 11 is composed of a known GPS receiver. For example, the GPS sensor 11 receives information from a GPS satellite (not shown) and calculates the current position (latitude and longitude) of a vehicle (hereinafter also referred to as a "target vehicle") on which an estimation device according to an embodiment is mounted. The GPS sensor 11 transmits current position data POS to the information processing device 14. The GPS sensor 11 may calculate the direction of the target vehicle based on a history of the current position, and add this data to the current position data POS.

[0021] The camera 12 captures an image of the external situation of the target vehicle. The camera 12 includes at least a camera that captures an image of the situation in the center in front of the target vehicle. The camera 12 may further include a camera for capturing an image of the front right side of the target vehicle, a camera for capturing an image of the front left side of the target vehicle, a camera for capturing an image of the rear side of the target vehicle, a camera for capturing an image of the right side and right rear side of the target vehicle, and a camera for capturing an image of the left side and left rear side of the target vehicle. The camera 12 transmits captured image data IMG to the information processing device 14.

[0022] The sign DB13 is formed in a storage device of the target vehicle. The sign DB13 stores sign data that combines road signs with information that the road signs have. The road signs include road signs provided on motorways (e.g., expressways) and road signs provided on roads other than motorways (e.g., general roads). In this specification, the former data is also referred to as "sign data HWY."

[0023] FIG. 2 is a diagram for explaining an example of the configuration of sign data HWY. In the example shown in FIG. 2, the sign data HWY is configured in a table format, in which information on road signs is stored for each country N(k). Note that country A, country B, ..., country X are examples of country (k), and country ND is set in advance as a country that is difficult to identify based on the current position data POS. In FIG. 2, speed limits on motorways, information on the structure of white lines (dividing lines) painted on motorways, and the colors of guide signs installed on motorways are given as examples of road signs.

[0024] The speed limit is set by the traffic laws of each country, and is typically an upper limit vehicle speed. The speed limit may be a recommended vehicle speed on a motorway. The structure of the white lines and the color of the guide signs are also set by the traffic laws of each country. Examples of the structure of the white lines include the length of one section when the white line is drawn in dashed lines, and the distance between two adjacent sections. In the example shown in FIG. 2, information on the structure of the white lines is set as a white line pattern that includes at least one of these characteristics. Examples of the colors of the guide signs are blue and green.

[0025] The information processing device 14 is a computer that performs various processes. The information processing device 14 includes, for example, at least one processor 15 and at least one memory 16. The processor 15 includes a CPU (Central Processing Unit). The memory 16 is a volatile memory such as a DDR memory, and expands various programs used by the processor 15 and temporarily stores various data. The various data stored in the memory 16 include current position data POS received from the GPS sensor 11 and image data IMG received from the camera 12.

[0026] The processor 15 executes software for target recognition processing, which is a computer program. The processor 15 also executes software for road type estimation processing. These pieces of software are stored in the memory 16 or recorded in a computer-readable recording medium. The processor 15 executes these pieces of software, whereby the information processing device 14 performs target recognition processing and road type estimation processing.

[0027] The target recognition process is a process for recognizing targets around the target vehicle. The target recognition process is performed based on image data IMG. Known methods such as machine learning are applied as a method for target recognition based on camera images such as image data IMG. The target recognition process recognizes static targets and dynamic targets around the target vehicle. Examples of static targets include lines (i.e., white lines) that define the lane in which the target vehicle is currently traveling, guardrails, and buildings. Examples of dynamic targets include pedestrians, bicycles, motorcycles, and automobiles. Information on targets recognized by the target recognition process is used in the road type estimation process.

[0028] The road type estimation process is a process for estimating the type of the road on which the target vehicle is traveling. The road type estimation process is performed based on the information of the target recognized by the target recognition process and the sign data HMY. An example of the road type estimation process will be described with reference to FIGS. 3 and 4.

[0029] 2. Road type estimation process 3 and 4 are flowcharts illustrating the flow of the road type estimation process performed by the information processing device 14 (processor 15). The routine shown in FIGs. 3 and 4 is repeatedly executed at a predetermined control period.

[0030] 3, first, the current position data POS is acquired (step S11). As already described, the current position data POS is the latitude and longitude data of the target vehicle acquired by the GPS sensor 11.

[0031] Following the processing of step S11, the country N(k) (k is A to Z or ND) in which the target vehicle is traveling is estimated (step S12). The processing of step S12 is performed based on the current position data POS acquired in step S11. The range of the country N(k) can be identified based on latitude and longitude data representing national borders. Therefore, for example, if the current position data POS is located within the range of a certain country N(k), the country N(k) in which the target vehicle is traveling can be identified.

[0032] Following the process of step S12, sign data HWY(k) is extracted (step S13) from the sign DB 13. The sign data HWY(k) is the sign data HWY corresponding to the country N(k) estimated in step S12.

[0033] 4, first, information on a target recognized by the target recognition process is acquired (step S21). As already described, the target recognition process is a process for recognizing targets around a target vehicle.

[0034] Following the process of step S21, it is determined whether or not the information on the recognized target object includes information on road signs (step S22). In the process of step S22, it is determined whether or not information on road signs has been acquired in the process of step S21, regardless of the type of road, such as an expressway or a general road. If the acquired information includes information on road signs, the process proceeds to step S23. If not, the current process ends.

[0035] In the process of step S23, the information of the road sign acquired in the process of step S21 is compared with the information of the road sign included in the sign data HWY(k) extracted in step S13 of Fig. 3. Then, it is determined whether or not these pieces of information match.

[0036] Here, consider the case where the information on the road sign acquired in the process of step S21 is information on the "vehicle speed limit." In this case, for example, the acquired vehicle speed limit value is compared with the vehicle speed limit value included in the sign data HWY(k). Then, if the former value is equal to or greater than the latter value, it is determined that the information matches.

[0037] Next, consider the case where the information of the road sign acquired in the process of step S21 is information on the "structure of the white line." In this case, for example, the pattern of the acquired structure of the white line is compared with the white line pattern included in the sign data HWY(k). Then, if the degree of match between the former and the latter is equal to or greater than a threshold, it is determined that these patterns match.

[0038] When the information of the road sign acquired in the process of step S21 is information on the "color of the guide sign," the color of the image area showing the acquired guide sign is estimated based on the average values ​​of the hue H, saturation S, and brightness V (HSV average value) of the image area. Then, it is determined whether the estimated color of the image area matches the sign color included in the sign data HWY(k).

[0039] In step S23, if any one of the information on "speed limit," "structure of white line," and "color of guide sign" is obtained in step S21, this obtained information is compared with the information included in the corresponding sign data HWY(k). If information on multiple types of road signs (for example, information on "speed limit" and "color of guide sign") is obtained, a comparison is made for the information on each road sign.

[0040] If the determination result in step S23 is positive, it is determined that the road on which the target vehicle is currently traveling is a freeway (step S24). If not, it is determined that the road on which the target vehicle is currently traveling is a road other than a freeway (step S25). Note that, if information on multiple types of road signs is obtained in the processing of step S21, it is determined that the road on which the target vehicle is currently traveling is a freeway (step S24) if a positive determination result is obtained for at least one of the road signs.

[0041] 3.Effects According to the embodiment described above, a road type estimation process is performed using the current position data POS, the sign data HMY, and the image data IMG. Therefore, it is possible to determine whether the road on which the target vehicle is currently traveling is a motorway without using map data. Therefore, it is possible to estimate the road type even in countries where the amount of map data is insufficient. When the road type is estimated using map data, it is also possible to complement this estimation result.

[0042] Furthermore, according to the embodiment, it is possible to omit the installation of an external communication device other than the GPS sensor 11 in the vehicle. Therefore, it becomes possible to estimate the road type even in a country or region where the infrastructure for communicating with a data providing device such as a central server is insufficient. Even if an external communication device is installed in the vehicle, it becomes possible to estimate the road type without relying on communication by this external communication device. [Explanation of symbols]

[0043] 1 Road type estimation device 11 GPS sensor 12 Camera 13. Tag Database 14 Information processing equipment 15 Processors 16 Memory POS current location data IMG Image data SIG Sign Data

Claims

1. An apparatus for estimating a type of road on which a vehicle is traveling, comprising: a database storing sign data consisting of combinations of road signs of expressways and information contained in the road signs; A memory in which image data of the surroundings of the vehicle and position data of the vehicle are stored; a processor that performs a recognition process for recognizing objects around the vehicle based on the image data and an estimation process for estimating a type of road on which the vehicle is traveling; Equipped with the information on the road signs of the motorway stored in the database includes information on the vehicle speed limit on the motorway, information on the color of guide signs provided on the motorway, and information on the structure of the dividing lines drawn on the motorway; The processor, in the estimation process, extracting sign data corresponding to the country in which the vehicle is traveling by referring to the database based on the location data; When a road sign is recognized around the vehicle in the recognition process, information indicated by the recognized road sign is compared with information of the road sign included in the extracted sign data; If the information indicated by the recognized road sign matches the information of the road sign included in the extracted sign data, it is estimated that the road on which the vehicle is traveling is a motorway. A road type estimation device comprising:

2. 2. The apparatus of claim 1, The processor, in the estimation process, When the recognized road signs include a plurality of types of road signs, comparing each piece of information indicated by the plurality of types of road signs with each piece of information of the road signs included in the extracted sign data; If the information indicated by the recognized road sign includes at least information that matches the information of the road sign included in the extracted sign data, it is estimated that the road on which the vehicle is traveling is a motorway. A road type estimation device comprising:

3. 1. A method for estimating a type of road on which a vehicle is traveling, comprising: acquiring image data of the surroundings of the vehicle and position data of the vehicle; a target recognition step of recognizing targets around the vehicle based on the image data; a step of extracting sign data corresponding to the country in which the vehicle is traveling, using the location data and a database in which sign data consisting of a combination of road signs of motorways and information possessed by the road signs is stored, the information possessed by the road signs of the motorways stored in the database including information on vehicle speed limits on motorways, information on the colors of guide signs provided on the motorways, and information on the structure of demarcation lines drawn on the motorways; a comparison step of comparing information indicated by the recognized road sign with information of the road sign included in the extracted sign data when a road sign is recognized around the vehicle in the target recognition step; an estimation step of estimating that the road on which the vehicle is traveling is a motorway when information indicated by the recognized road sign matches information held by a road sign included in the extracted sign data; A road type estimating method comprising the steps of:

4. 4. The method of claim 3, When a plurality of types of road signs are recognized around the vehicle in the target recognition step, the comparison step compares each piece of information indicated by the plurality of types of road signs with each piece of information of the road signs included in the extracted sign data; When the information indicated by the recognized road sign includes at least information that matches the information of the road sign included in the extracted sign data, the estimation step estimates that the road on which the vehicle is traveling is a motorway. A road type estimating method comprising:

Images