Map reliability determination device and driving assistance device

Abstract

To provide a user with indicators to a map.SOLUTION: A map reliability determination device 50 includes: a travel trajectory acquisition unit 112 for acquiring a travel trajectory of a predetermined section where an own vehicle has traveled; a boundary recognition unit 113 for recognizing a pair of right and left lane boundaries that define lanes within the predetermined section where the own vehicle has traveled, based on map information in the vicinity of the own vehicle; a displacement amount calculation unit 114 for calculating a displacement amount between the travel trajectory acquired by the travel trajectory acquisition unit 112 and the pair of right and left lane boundaries recognized by the boundary recognition unit 113; a reliability determination unit 115 for determining the reliability of the pair of right and left lane boundaries recognized by the boundary recognition unit 113 based on the displacement amount calculated by the displacement calculation unit 114; and a map updating unit 116 for outputting reliability information including a determination result of the reliability determination unit 115.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a map reliability determination device that determines the reliability of road map information and a driving assistance device. [Background technology]

[0002] Conventionally, as this type of device, a device is known that detects the surrounding environment of a traveling vehicle using an on-board sensor and generates map information based on sensor data from the on-board sensor (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-164005 Summary of the Invention [Problem to be solved by the invention]

[0004] However, maps generated by the device described in Patent Document 1 may contain errors, and it is preferable to provide some kind of indicator to the user in order to use such maps. [Means for solving the problem]

[0005] The map reliability determination device according to one aspect of the present invention includes: a trajectory acquisition unit that acquires a travel trajectory of a predetermined section traveled by a host vehicle; a storage unit that stores an environmental map including lane boundary lines around the vehicle, the environmental map being generated based on the detection results of an external environment detection unit that detects the external environment around the vehicle; and Based on this, car A recognition unit recognizes lane boundary lines that define a line, and based on a deviation between the travel trajectory acquired by the trajectory acquisition unit and the pair of left and right lane boundary lines recognized by the recognition unit, Environmental Map and a reliability determination unit that determines the reliability of the

[0006] A driving assistance device according to another aspect of the present invention includes the above-described map reliability determination device, a road recognition unit that recognizes a road ahead in the traveling direction of a host vehicle traveling in an autonomous driving mode, and a map reliability determination device. memory By department memory The route recognized by the route recognition unit Environmental Map and a request unit that outputs request information including a request for a driver change to a driver's shift based on the reliability indicated by the reliability information acquired by the reliability acquisition unit. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a user with an indication for using a map. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an overall configuration of a vehicle control system according to an embodiment of the present invention; [Figure 2] FIG. 10 is a diagram for explaining deviation of lane boundary lines; [Figure 3] 1 is a block diagram showing a schematic configuration of a map reliability determination device according to an embodiment of the present invention; [Figure 4] 4 is a flowchart showing an example of processing executed by the controller of FIG. 3; [Figure 5A] FIG. 4 is a diagram for explaining the reliability of lane boundary lines. [Figure 5B] FIG. 4 is a diagram for explaining the reliability of lane boundary lines. [Figure 5C] FIG. 10 is a diagram showing an example of lane boundary lines that need to be corrected. [Figure 6] 1 is a block diagram showing a schematic configuration of a driving assistance device according to an embodiment of the present invention; [Figure 7] 7 is a flowchart showing an example of processing executed by the controller of FIG. 6; DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to Figs. 1 to 7. A vehicle control system according to an embodiment of the present invention includes a map reliability determination device and a driving assistance device. The map reliability determination device is configured to determine the reliability of road map information. The driving assistance device is configured to provide driving assistance based on the road map information whose reliability has been determined by the map reliability determination device.

[0010] The vehicle control system can be applied to both vehicles with an automatic driving function, i.e., an automatic driving vehicle, and vehicles without an automatic driving function, i.e., a manually driven vehicle. Note that the vehicle to which the vehicle control system according to this embodiment is applied may be referred to as the host vehicle to distinguish it from other vehicles. In the following, the host vehicle will be described as an automatic driving vehicle. An automatic driving vehicle has not only an automatic driving function but also a manual driving function, and can also be configured as a manually driven vehicle. In other words, the host vehicle (automatically driven vehicle) can travel not only in an automatic driving mode in which no driving operation by the driver is required, but also in a manual driving mode in which the driver operates the vehicle.

[0011] The host vehicle may be any of an engine vehicle having an internal combustion engine (engine) as a driving source, an electric vehicle having a traction motor as a driving source, and a hybrid vehicle having an engine and a traction motor as driving sources. Fig. 1 is a block diagram showing the overall configuration of a vehicle control system 100 according to an embodiment of the present invention.

[0012] As shown in FIG. 1, the vehicle control system 100 mainly includes a controller 10, a group of external sensors 1 each communicatively connected to the controller 10 via a CAN communication line or the like, a group of internal sensors 2, an input / output device 3, a positioning unit 4, a map database 5, a navigation device 6, a communication unit 7, and a driving actuator AC.

[0013] The external sensor group 1 is a collective term for a plurality of sensors (external sensors) that detect the external situation, which is information about the surroundings of the vehicle. For example, the external sensor group 1 includes a lidar that detects the position (distance and direction from the vehicle) of objects around the vehicle by emitting laser light and detecting reflected light, a radar that detects the position of objects around the vehicle by emitting electromagnetic waves and detecting reflected waves, and a camera that has an imaging element such as a CCD or CMOS and captures images of the surroundings (front, rear, and sides) of the vehicle.

[0014] The internal sensor group 2 is a collective term for a plurality of sensors (internal sensors) that detect the driving state of the host vehicle. For example, the internal sensor group 2 includes a vehicle speed sensor that detects the vehicle speed of the host vehicle, an acceleration sensor that detects the acceleration in the forward / backward and left / right directions of the host vehicle, a rotation speed sensor that detects the rotation speed of the driving source, etc. The internal sensor group 2 also includes sensors that detect the driving operations of the driver in manual driving mode, such as operation of the accelerator pedal, operation of the brake pedal, operation of the steering wheel, etc.

[0015] The input / output device 3 is a general term for devices that input commands from the driver and output information to the driver. For example, the input / output device 3 includes various switches through which the driver inputs various commands by operating operating members, a microphone through which the driver inputs commands by voice, a display that provides information to the driver via displayed images, and a speaker that provides information to the driver by voice.

[0016] The positioning unit (GNSS unit) 4 has a positioning sensor that receives positioning signals transmitted from positioning satellites. The positioning sensor can also be included in the internal sensor group 2. The positioning satellite is an artificial satellite such as a GPS satellite or a quasi-zenith satellite. The positioning unit 4 measures the current position (latitude, longitude, altitude) of the vehicle using the positioning information received by the positioning sensor.

[0017] The map database 5 is a device that stores general map information used in the navigation device 6, and is configured with, for example, a hard disk or semiconductor elements. The map information includes road position information, road shape information (curvature, etc.), and position information of intersections and branch points. Note that the map information stored in the map database 5 is different from the highly accurate map information stored in the memory unit 12 of the controller 10.

[0018] The navigation device 6 is a device that searches for a target route on roads to a destination input by the driver and provides guidance along the target route. The input of the destination and guidance along the target route are performed via the input / output device 3. The target route is calculated based on the current position of the vehicle measured by the positioning unit 4 and map information stored in the map database 5. The current position of the vehicle can also be measured using detection values ​​from the external sensor group 1, and the target route can be calculated based on this current position and high-precision map information stored in the memory unit 12.

[0019] The communication unit 7 communicates with various servers (not shown) via networks including wireless communication networks such as the Internet and mobile phone networks, and acquires map information, driving history information, traffic information, and the like from the servers periodically or at any timing. Networks include not only public wireless communication networks but also closed communication networks established for each predetermined management area, such as wireless LAN, Wi-Fi (registered trademark), Bluetooth (registered trademark), and the like. The acquired map information is output to the map database 5 and the storage unit 12, where the map information is updated. Communication with other vehicles is also possible via the communication unit 7.

[0020] Actuators AC are driving actuators for controlling the driving of the host vehicle. When the driving source is an engine, actuators AC include a throttle actuator that adjusts the opening of the engine's throttle valve (throttle opening). When the driving source is a driving motor, actuators AC include the driving motor. Actuators AC also include a brake actuator that operates the host vehicle's braking device and a steering actuator that drives the steering device.

[0021] The controller 10 is composed of an electronic control unit (ECU). More specifically, the controller 10 includes a computer having an arithmetic unit 11 such as a CPU (microprocessor), a storage unit 12 such as a ROM and RAM, and other peripheral circuits (not shown) such as an I / O interface. Note that although multiple ECUs with different functions, such as an engine control ECU, a traction motor control ECU, and a braking device ECU, can be provided separately, for convenience, the controller 10 is shown in FIG. 1 as a collection of these ECUs.

[0022] High-precision road map information is stored in the memory unit 12. This road map information includes road position information, road shape information (curvature, etc.), road gradient information, intersection and branch point position information, number of lanes information, lane width and position information for each lane (information on lane center positions and lane boundary lines), position information of landmarks (traffic lights, signs, buildings, etc.) as markers on the map, and road surface profile information such as road surface irregularities. The map information stored in the memory unit 12 includes map information acquired from outside the vehicle via the communication unit 7 and map information created by the vehicle itself using detection values ​​from the external sensor group 1 or detection values ​​from the external sensor group 1 and the internal sensor group 2.

[0023] The calculation unit 11 has, as functional components, a vehicle position recognition unit 13, an external environment recognition unit 14, a behavior plan generation unit 15, and a driving control unit 16.

[0024] The vehicle position recognition unit 13 recognizes the position of the vehicle on the map (own vehicle position) based on the vehicle position information obtained by the positioning unit 4 and the map information in the map database 5. The vehicle position may be recognized using the map information stored in the storage unit 12 and information about the surroundings of the vehicle detected by the external sensor group 1, thereby enabling the vehicle position to be recognized with high accuracy. Note that when the vehicle position can be measured by an external sensor installed on or beside the road, the vehicle position can also be recognized by communicating with the sensor via the communication unit 7.

[0025] The external environment recognition unit 14 recognizes the external situation around the vehicle based on signals from the external sensor group 1, such as a lidar, radar, and camera. For example, it recognizes the positions, speeds, and accelerations of surrounding vehicles (vehicles ahead and vehicles behind) traveling around the vehicle, the positions of surrounding vehicles stopped or parked around the vehicle, and the positions and states of other objects. Examples of other objects include signs, traffic lights, markings such as road dividing lines and stop lines, buildings, guardrails, utility poles, signs, pedestrians, bicycles, etc. Examples of the states of other objects include the color of traffic lights (red, green, yellow), the moving speed and direction of pedestrians and bicycles, etc.

[0026] The behavior plan generation unit 15 generates a driving trajectory (target trajectory) of the host vehicle from the current time to a predetermined time ahead based on, for example, a target route calculated by the navigation device 6, map information stored in the memory unit 12, the host vehicle position recognized by the host vehicle position recognition unit 13, and external conditions recognized by the external environment recognition unit 14. When there are multiple trajectories that are candidates for the target trajectory on the target route, the behavior plan generation unit 15 selects an optimal trajectory from among them that satisfies criteria such as compliance with laws and regulations and efficient and safe driving, and sets the selected trajectory as the target trajectory. The behavior plan generation unit 15 then generates a behavior plan according to the generated target trajectory. The behavior plan generation unit 15 generates various behavior plans corresponding to overtaking driving to overtake a preceding vehicle, lane-changing driving to change lanes, following driving to follow a preceding vehicle, lane-keeping driving to maintain the vehicle in its lane without deviating from the lane, decelerating driving, accelerating driving, etc. When generating the target trajectory, the behavior plan generation unit 15 first determines a driving mode and generates the target trajectory based on the driving mode.

[0027] In the autonomous driving mode, the driving control unit 16 controls each actuator AC so that the host vehicle travels along the target trajectory generated by the behavior plan generation unit 15. More specifically, in the autonomous driving mode, the driving control unit 16 calculates a required driving force for achieving the target acceleration per unit time calculated by the behavior plan generation unit 15, taking into account the driving resistance determined by the road gradient, etc. Then, for example, the driving control unit 16 feedback-controls the actuators AC so that the actual acceleration detected by the internal sensor group 2 becomes the target acceleration. In other words, the driving control unit 16 controls the actuators AC so that the host vehicle travels at the target vehicle speed and target acceleration. Note that when the driving mode is the manual driving mode, the driving control unit 16 controls each actuator AC in accordance with a driving command (such as a steering operation) from the driver acquired by the internal sensor group 2.

[0028] When the vehicle is traveling in manual driving mode, the vehicle control system 100 configured as described above recognizes boundary lines (hereinafter referred to as lane boundary lines) that define the lanes of the road on which the vehicle is traveling, based on sensor values ​​acquired by the external sensor group 1, generates road map information including the lane boundary lines, and stores the generated road map information in the memory unit 12. When the vehicle is traveling in autonomous driving mode, the vehicle control system 100 recognizes lane boundary lines on the right and left sides of the vehicle based on the road map information stored in the memory unit 12, and controls the actuator AC so that the vehicle travels in the center of the left and right lane boundary lines.

[0029] However, when the sensor values ​​of the external sensor group 1 contain errors or when there is a change in the road structure, the positions of the actual lane boundary lines and the lane boundary lines indicated by the road map information may deviate. FIG. 2 is a diagram for explaining the deviation of lane boundary lines. In FIG. 2, solid lines RL and RR schematically represent actual boundary lines (hereinafter, sometimes referred to as actual boundary lines) that define the lane LN on which the host vehicle 101 is traveling. The solid line RL represents the actual boundary line on the left side of the lane LN, and the solid line RR represents the actual boundary line on the right side of the lane LN. The dashed-dotted lines VL and VR schematically represent the left and right boundary lines (hereinafter, sometimes referred to as virtual boundary lines) of the lane LN indicated by the road map information. In the example shown in FIG. 2, the positions of the virtual boundary lines VL and VR in the vehicle width direction are gradually deviated to the left from the actual boundary lines RL and RR. In this case, if a target trajectory for automatic driving is generated based on the center line VC of the virtual boundary lines VL and VR, the traveling position of the host vehicle 101 may deviate from the center of the lane or the host vehicle 101 may deviate from the road. In the example of Fig. 2, the traveling position of the host vehicle 101 may gradually shift to the left side of the lane LN, and the host vehicle 101 may eventually deviate from the road at point P1. Therefore, in order to address such problems, the map reliability determination device in this embodiment is configured as follows.

[0030] 3 is a block diagram showing a schematic configuration of a map reliability determination device 50 according to an embodiment of the present invention, and shows the configuration when the host vehicle 101 is traveling mainly in manual driving mode. The map reliability determination device 50 is included in the vehicle control system 100 of FIG. 1. As shown in FIG. 3, the map reliability determination device 50 has a camera 1a, a wheel speed sensor 4a, a steering angle sensor 4b, and a controller 10.

[0031] The camera 1a is a stereo camera having an imaging element (image sensor) such as a CCD or CMOS, and constitutes part of the external sensor group 1 in FIG. 1. The camera 1a may be a monocular camera. The camera 1a detects the external environment around the host vehicle 101. The camera 1a is attached, for example, to a predetermined position in front of the host vehicle 101, and continuously captures images of the space ahead of the host vehicle 101 to obtain images of objects (camera images). The objects include boundary lines such as lane markings that define the lane in which the host vehicle 101 is traveling (for example, actual boundary lines RL and RR in FIG. 2).

[0032] The wheel speed sensor 4a detects the speed of the wheels of the vehicle 101. The steering angle sensor 4b detects the steering angle of the wheels steered via the steering wheel.

[0033] The controller 10 in FIG. 3 has a map generating unit 111 and a storage unit 12 as functional components.

[0034] While driving in manual driving mode, the map generation unit 111 generates map information (environmental map) consisting of three-dimensional point cloud data using detection values ​​detected by the camera 1a. Specifically, edges indicating the contours of objects are extracted from the camera image acquired by the camera 1a based on brightness and color information for each pixel, and feature points are extracted using the edge information. Feature points are, for example, intersections of edges, and correspond to corners of buildings, corners of road signs, edges of lane markings, etc. The map generation unit 111 sequentially plots the extracted feature points on the environmental map, thereby generating an environmental map of the area around the road on which the vehicle 101 has traveled. The map generation unit 111 recognizes lane boundaries of the road on which the vehicle 101 is traveling based on the extracted feature points, and stores position information of the recognized lane boundaries in the environmental map. In places where there are no dividing lines, such as roads in residential areas or in intersections, lane boundaries are recognized based on recognition information about the surroundings of the vehicle 101, such as the contours (edges) of buildings, curbs, plants, etc. lined up along the road, and the travel paths of vehicles (leading vehicles and oncoming vehicles) around the vehicle 101. The generated environmental map is stored in the storage unit 12.

[0035] The controller 10 in FIG. 3 further includes, as functional components, a driving trajectory acquisition unit (hereinafter simply referred to as the trajectory acquisition unit) 112, a boundary recognition unit 113, a deviation amount calculation unit 114, a reliability determination unit 115, and a map update unit 116.

[0036] The trajectory acquisition unit 112, boundary line recognition unit 113, deviation amount calculation unit 114, reliability determination unit 115, and map update unit 116 are configured to function as follows during pre-driving: Pre-driving is driving in manual driving mode that is performed to determine the reliability of the environmental map generated by the map generation unit 111 before driving in automatic driving mode on a road for which the environmental map has been generated by the map generation unit 111.

[0037] The trajectory acquisition unit 112 acquires a travel trajectory of a target section traveled by the host vehicle 101. More specifically, the trajectory acquisition unit 112 calculates and acquires a travel trajectory based on the position (time-series position) of the host vehicle 101 measured by the positioning unit 4 while the host vehicle 101 is traveling through the target section. The target section is a section from the current traveling position of the host vehicle 101 to a position a predetermined distance behind, and the memory unit 12 stores sensor data of the positioning unit 4 acquired while the host vehicle 101 is traveling through the target section at least until the calculation of the traveling trajectory of the target section by the trajectory acquisition unit 112 is completed. Note that the travel trajectory may be calculated based on sensor data from the wheel speed sensor 4a and the steering angle sensor 4b.

[0038] The boundary line recognition unit 113 recognizes a pair of left and right boundary lines that define the lane in the target section in which the host vehicle 101 has traveled, based on the environmental map stored in the memory unit 12. More specifically, the boundary line recognition unit 113 acquires position information of the pair of left and right boundary lines that define the lane in which the host vehicle 101 has traveled, from the environmental map.

[0039] The deviation amount calculation unit 114 calculates the deviation amount between the travel path of the vehicle 101 acquired by the path acquisition unit 112 and the pair of left and right lane boundary lines recognized by the boundary line recognition unit 113. Traces and the center line of a pair of left and right lane boundary lines (line VC in FIG. 2). The deviation amount calculation unit 114 sets calculation points at regular intervals on the travel trajectory of the vehicle 101, and calculates the deviation amount at each calculation point.

[0040] The reliability determination unit 115 determines the reliability of the pair of left and right lane boundary lines recognized by the boundary line recognition unit 113 based on the deviation calculated by the deviation amount calculation unit 114. In particular, the reliability determination unit 115 determines the reliability so that the smaller the deviation calculated by the deviation amount calculation unit 114, the higher the reliability. More specifically, the reliability determination unit 115 calculates the maximum value of the deviation amounts at each calculation point set within the target section, and determines the reliability so that the smaller the maximum value, the higher the reliability. Note that the reliability determination unit 115 may determine the reliability using other statistical values, such as the sum or average value of the deviation amounts, instead of the maximum value of the deviation amounts.

[0041] The map update unit 116 outputs reliability information including the determination result of the reliability determination unit 115 to the storage unit 12. In particular, the reliability information is stored in the environmental map stored in the storage unit 12 in association with the position information of the target section. If the reliability information of the target section is already included in the environmental map, the reliability information of the target section included in the environmental map is updated (overwritten). The position information of the target section is information indicating the latitude and longitude of the start point and end point of the target section. Note that the position information of the target section may be any other information as long as it is information that can identify the position of the target section.

[0042] Furthermore, when the deviation calculated by the deviation amount calculation unit 114 is equal to or greater than a predetermined amount, the map update unit 116 corrects the environmental map stored in the memory unit 12. Specifically, when the deviation calculated by the deviation amount calculation unit 114 is equal to or greater than half the lane width, the map update unit 116 determines that the center lines of the pair of left and right lane boundary lines recognized by the boundary line recognition unit 113 protrude outside the actual lane, and corrects the environmental map stored in the memory unit 12. More specifically, the map update unit 116 corrects the position information of the lane boundary lines (the pair of left and right lane boundary lines) of the target section stored in the environmental map so that the center lines of the lane boundary lines overlap the driving trajectory of the host vehicle 101 in the target section.

[0043] Fig. 4 is a flowchart showing an example of processing executed by the controller 10 of Fig. 3 in accordance with a predetermined program. The processing shown in this flowchart is started, for example, when the host vehicle 101 is traveling in advance in manual driving mode, and is repeated at predetermined intervals.

[0044] In step S11, the driving trajectory of the target section traveled by the host vehicle 101 is acquired. In step S12, a pair of left and right lane boundary lines that define the lanes within the target section traveled by the host vehicle 101 is recognized based on the environmental map stored in the memory unit 12. In step S13, the amount of deviation between the driving trajectory acquired in step S11 and the center lines of the pair of left and right lane boundary lines recognized in step S12 is calculated. In step S14, the reliability of the pair of left and right lane boundary lines recognized in step S12 is determined based on the deviation amount calculated in step S13. In step S15, it is determined whether correction of the lane boundary lines is necessary. More specifically, based on the deviation amount calculated in step S13, it is determined whether the center lines of the pair of left and right lane boundary lines recognized in step S12 extend outside the actual lane. If the result in step S15 is negative, the environmental map is updated in step S16, and the process ends. Specifically, reliability information including the determination result of step S13 is associated with position information of the target section and stored in the environmental map of the storage unit 12. If the result of step S15 is affirmative, lane boundary lines on the environmental map are regenerated in step S17. Specifically, the position information of the lane boundary lines of the target section is corrected based on the traveling trajectory acquired in step S11.

[0045] Here, the determination of the reliability of lane boundary lines will be described. FIGS. 5A and 5B are diagrams for explaining the reliability of lane boundary lines. In FIG. 5A, the position of the driving trajectory RT of the target section acquired in step S11 substantially coincides with the position of the center line VC of the pair of left and right lane boundary lines (virtual boundary lines VL, VR) of the target section recognized in step S12. In this case, it is determined that the reliability of the virtual boundary lines VL, VR is high, that is, automated driving is possible in this target section (step S14). In FIG. 5B, the position of the center line VC of the virtual boundary lines VL, VR gradually approaches the real boundary line RR on the right. In this case, it is determined that the reliability of the virtual boundary lines VL, VR is low, that is, the automated driving level needs to be lowered before entering this target section, more specifically, the occupant needs to be requested to keep their hands on the vehicle (step S14). FIG. 5C is a diagram showing an example of a lane boundary line (virtual boundary line) that requires correction. In FIG. 5C, the center line VC of the virtual boundary lines VL, VR protrudes to the right of the actual lane. In this case, it is determined that the position information of the lane boundary lines stored in the environmental map needs to be corrected (step S15). Note that instead of determining the reliability in two stages, "high" and "low," it may be determined in three or more stages depending on the length of the distance between the traveling trajectory RT and the center line VC of the virtual boundary lines VL and VR (the distance GA in FIG. 5B).

[0046] FIG. 6 is a block diagram showing a schematic configuration of a driving assistance device 60 according to an embodiment of the present invention, illustrating a configuration in which driving assistance is performed based on an environmental map whose reliability has been determined by a map reliability determination device 50. The driving assistance device 60 is included in the vehicle control system 100 of FIG. 1. As shown in FIG. 6, the driving assistance device 60 has a camera 1a, a controller 10, an actuator AC, and a notification unit 3a. Although not shown in the figure, signals from an external sensor group 1, an internal sensor group 2, etc. are input to the controller 10 (see FIG. 1).

[0047] The notification unit 3a is part of the input / output device 3 in Fig. 1 and is configured with a display that notifies the driver of information by display, a speaker that notifies the driver of information by voice, etc. The controller 10 in Fig. 6 has, as its functional configuration, a road recognition unit 61, a driving assistance unit 62, a reliability acquisition unit 63, a request unit 64, and a memory unit 12.

[0048] The lane recognition unit 61 recognizes the lane ahead in the direction of travel of the host vehicle 101 while it is traveling. Specifically, the lane recognition unit 61 recognizes a pair of left and right dividing lines that define the lane in which the host vehicle 101 is traveling as lane boundary lines, based on a camera image of the area ahead of the host vehicle acquired by the camera 1a. When the host vehicle 101 is traveling on a road without dividing lines, the lane recognition unit 61 recognizes the pair of left and right lane boundary lines based on recognition information of objects around the host vehicle (surrounding vehicles, buildings lined up along the road, etc.). The lane recognition unit 61 recognizes the area sandwiched between the recognized pair of left and right lane boundary lines as the lane of the host vehicle 101. The lane recognition unit 61 may recognize the lane of the host vehicle 101 based on information acquired by radar or lidar together with the camera image.

[0049] The driving assistance unit 62 assists the vehicle 101 in driving based on the target route calculated by the navigation device 6 and the environmental map (learned map) stored in the memory unit 12. At this time, the driving assistance unit 62 controls the actuator AC so that the vehicle 101 travels in the center of the road recognized by the road recognition unit 61 (on the center line of the pair of left and right lane boundary lines).

[0050] The reliability acquisition unit 63 acquires reliability information corresponding to the road recognized by the road recognition unit 61 from the learning map stored in the memory unit 12. Specifically, the reliability acquisition unit 63 acquires reliability information corresponding to a section from the current position of the vehicle 101 to a position that is a certain distance away in the traveling direction, from the environmental map stored in the memory unit 12. This certain distance is a distance that allows a sufficient amount of time for the driver to take over the driving operation, and is determined based on the current traveling speed of the vehicle 101.

[0051] The request unit 64 outputs request information, including a request for the occupant to take over driving, via the notification unit 3a based on the reliability indicated by the reliability information acquired by the reliability acquisition unit 63. Specifically, when the reliability is below a predetermined level, the request unit 64 determines that there is a possibility that the vehicle 101 will deviate from the center of the lane or deviate from the road if the vehicle 101 travels along the road recognized by the road recognition unit 61, and outputs request information to request the occupant to take over driving. The request information includes image information to be displayed on the notification unit 3a (display), specifically, image information that prompts the occupant to operate the steering wheel (hands-on) and image information that notifies or warns the occupant of a switch to manual driving mode. The request information may also include audio information to be output to the notification unit 3a (speaker), specifically, audio information that prompts the occupant to take over driving mode and audio information that notifies or warns the occupant of a switch to manual driving mode.

[0052] Fig. 7 is a flowchart showing an example of processing executed by the controller 10 of Fig. 6 in accordance with a predetermined program. The processing shown in this flowchart is started, for example, when the vehicle 101 is traveling in an autonomous driving mode, and is repeated at a predetermined interval.

[0053] First, in step S21, the road ahead in the direction of travel of the vehicle 101 while it is traveling is recognized. In step S22, reliability information corresponding to the road recognized in step S21 is obtained from the learned map stored in the memory unit 12. In step S23, it is determined whether the reliability indicated by the reliability information obtained in step S22 is less than a predetermined level. If the result in step S23 is negative, the processing ends. If the result in step S23 is positive, request information is output in step S24 to request the occupant to take over driving. Note that the content of the request information may be different depending on the level of reliability. For example, request information requesting only a hands-on driving position from the occupant may be output.

[0054] According to this embodiment, the following effects can be achieved. (1) The map reliability determination device 50 includes a trajectory acquisition unit 112 that acquires a driving trajectory of a predetermined section (target section) traveled by the host vehicle 101, a boundary line recognition unit 113 that recognizes a pair of left and right lane boundary lines that define the lane traveled by the host vehicle 101 in the predetermined section based on map information about the area around the host vehicle 101, a deviation amount calculation unit 114 that calculates the amount of deviation between the driving trajectory acquired by the trajectory acquisition unit 112 and the pair of left and right lane boundary lines recognized by the boundary line recognition unit 113, a reliability determination unit 115 that determines the reliability of the pair of left and right lane boundary lines recognized by the boundary line recognition unit 113 based on the amount of deviation calculated by the deviation amount calculation unit 114, and a map update unit 116 that outputs reliability information including the determination result of the reliability determination unit 115. This makes it possible to provide a user with an index for evaluating the reliability of a map, and to appropriately determine whether autonomous driving using the map is possible.

[0055] (2) The map reliability determination device 50 further includes a camera 1a that detects the external environment surrounding the vehicle 101, a map generation unit 111 that generates map information (environmental map) of the area around the vehicle 101 based on the information on the external environment detected by the camera 1a, and a storage unit 12 that stores the map information generated by the map generation unit 111. The map update unit 116 associates reliability information including the determination result of the reliability determination unit 115 with position information of a predetermined section and stores the information in the map information stored in the storage unit 12. This makes it possible to provide the user with an index for evaluating the reliability of the learned map (environmental map), and to appropriately determine whether autonomous driving using the learned map is possible.

[0056] (3) When the deviation calculated by the deviation calculation unit 114 is equal to or greater than a predetermined amount, the map update unit 116 further corrects the map information stored in the memory unit 12. This corrects the positions of the lane markings on the map to correspond to the actual lane markings, thereby improving the reliability of the map.

[0057] (4) The driving assistance device 60 includes the map reliability determination device 50 described above, a lane recognition unit 61 that recognizes the lane ahead in the direction of travel of the host vehicle 101 traveling in autonomous driving mode, a reliability acquisition unit 63 that acquires reliability information indicating the reliability of lane boundaries of the lane recognized by the lane recognition unit 61, output from the map update unit 116 of the map reliability determination device 50, and a request unit 64 that outputs request information including a request to the occupant to take over driving based on the reliability indicated by the reliability information acquired by the reliability acquisition unit 63. The request unit 64 outputs the request information when the reliability indicated by the reliability information acquired by the reliability acquisition unit 63 is below a predetermined level. This allows the occupant to appropriately request a change of driving during autonomous driving using a map. This improves traffic safety on roads on which autonomous vehicles travel.

[0058] The above-described embodiment can be modified in various ways. Several modifications will be described below. In the above-described embodiment, the camera 1a detects the external environment surrounding the vehicle 101. However, the external environment may be detected using a lidar or the like, and the configuration of the external environment detection unit is not limited to the above. In the above-described embodiment, the map generation unit 111 generates the environmental map while driving in manual driving mode. However, the environmental map may be generated while driving in automatic driving mode. In the above-described embodiment, the map generation unit 111 generates the environmental map based on camera images. However, instead of the camera 1a, data acquired by a radar or lidar may be used to extract feature points of objects around the vehicle 101 and generate the environmental map. The configuration of the map generation unit is not limited to the above.

[0059] In the above embodiment, the map update unit 116 as an output unit outputs (stores) reliability information including the determination result of the reliability determination unit 115 to the map information stored in the storage unit 12. However, the configuration of the output unit is not limited to this. The output unit may superimpose the reliability information on the map information displayed on the display. Specifically, roads in sections associated with the reliability information may be displayed in different colors depending on the reliability indicated by the reliability information. The output unit may also output information (such as location information) of sections with low reliability, for example, sections with reliability below a predetermined level, to the navigation device 6. More specifically, the output unit may output a search instruction to the navigation device 6 along with information about sections with low reliability so that, when the navigation device 6 searches for a target route to a destination input by the driver, target routes including sections with low reliability are preferentially searched. Furthermore, the output unit may display information on the display to prompt the user to drive the target route preferentially searched for in manual driving mode. This allows lane boundary lines in sections with low reliability to be regenerated, further improving the reliability of the map.

[0060] Furthermore, in the above embodiment, the map update unit 116 as a correction unit corrects the environmental map stored in the storage unit 12 when the amount of deviation calculated by the deviation amount calculation unit 114 is a predetermined amount, more specifically, equal to or greater than half the lane width. However, the predetermined amount used to determine whether to correct the environmental map may be set to a value other than half the lane width depending on the accuracy required of the environmental map, etc.

[0061] In addition, in the above embodiment, an example was described in which the pre-driving to determine the reliability of the environmental map generated by the map generation unit 111 is performed in manual driving mode, but if the vehicle 101 has an automatic driving function that enables autonomous driving while recognizing the road based on camera images, the pre-driving may be performed in automatic driving mode.

[0062] Furthermore, in the above embodiment, an example has been described in which the vehicle control system 100 (map reliability determination device 50) has the map generation unit 111, but the vehicle control system does not have to have a map generation unit. In this case, the vehicle control system may share an environmental map with a vehicle control system of another vehicle that has a map generation unit, and determine the reliability of the environmental map obtained by the other vehicle. Furthermore, the vehicle control system may assist driving based on the environmental map obtained by the other vehicle.

[0063] Furthermore, in the above embodiment, an example has been described in which the vehicle control system 100 functions as the map reliability determination device 50 and the driving assistance device 60, but the vehicle control system 100 may have only the function of the map reliability determination device 50. In this case, information obtained by the map reliability determination device 50 may be shared with vehicle control systems of other vehicles, and the other vehicles may use the information from the map reliability determination device 50 to provide driving assistance.

[0064] The above description is merely an example, and the present invention is not limited to the above-described embodiment and modifications, as long as the features of the present invention are not impaired. One or more of the above-described embodiment and modifications can be arbitrarily combined, and modifications can also be combined with each other. [Explanation of symbols]

[0065] 10 Controller, 12 Memory unit, 1a Camera, 3a Notification unit, 50 Map reliability determination device, 60 Driving assistance device, 61 Road recognition unit, 62 Driving assistance unit, 63 Reliability acquisition unit, 64 Request unit, 111 Map generation unit, 112 Travel trajectory acquisition unit (trajectory acquisition unit), 113 Boundary recognition unit, 114 Deviation amount calculation unit, 115 Reliability determination unit, 116 Map update unit

Claims

1. a trajectory acquisition unit that acquires a travel trajectory of a predetermined section traveled by the host vehicle; a storage unit configured to store an environmental map including lane boundary lines around the vehicle, the environmental map being generated based on a detection result of an external environment detection unit configured to detect an external environment around the vehicle; a recognition unit that recognizes lane boundary lines that define lanes within the predetermined section based on the environmental map stored in the storage unit; a reliability determination unit that determines the reliability of the environmental map based on a deviation between the driving trajectory acquired by the trajectory acquisition unit and the lane boundary line recognized by the recognition unit.

2. 2. The map reliability determination device according to claim 1, an external environment detection unit that detects an external environment around the vehicle; a map generation unit that generates map information about the surroundings of the vehicle based on information about the external environment detected by the external environment detection unit; a correction unit that corrects the map information stored in the memory unit when the deviation is equal to or greater than a predetermined amount or when the reliability determined by the reliability determination unit is less than a predetermined amount.

3. 3. The map reliability determination device according to claim 2, The map reliability determination device is characterized in that the storage unit associates reliability information including the determination result of the reliability determination unit with the location information of the specified section and stores it in the map information stored in the storage unit.

4. The map reliability determination device according to claim 3 ; a road recognition unit that recognizes a road ahead in the traveling direction of the host vehicle while the host vehicle is traveling in an autonomous driving mode; a reliability acquisition unit that acquires reliability information that indicates the reliability of the environmental map of the road recognized by the road recognition unit, the reliability information being stored in the storage unit of the map reliability determination device; A driving assistance device characterized by comprising: a request unit that outputs request information including a request for a driver change to an occupant based on the reliability indicated by the reliability information acquired by the reliability acquisition unit.

5. The driving assistance device according to claim 4, The driving assistance device is characterized in that the request unit outputs the request information when the reliability indicated by the reliability information acquired by the reliability acquisition unit is less than a predetermined level.

Images