CN116740957A - Road recognition device - Google Patents

Abstract

The road recognition device is provided with: a detection unit that detects a road marking of a road on which the host vehicle is traveling; a road marking discriminating unit that discriminates a type of the road marking corresponding to the color and shape of the road marking detected by the detecting unit; and a road determination unit that determines whether or not the road being traveled is a bidirectional traffic road through which bidirectional traffic is performed, based on road marking information including the information on the type of the road marking identified by the road marking identification unit.

Description

Road recognition device

Technical Field

The present invention relates to a road identification device for identifying a type of a road in running.

Background

As such a device, a device for determining whether or not a road in running is a road passing in both directions has been conventionally known. For example, patent document 1 describes the following device: based on map information including current position information of a vehicle and information on a road type acquired from a navigation device, it is determined whether or not a road in running is a road passing in both directions.

However, as in the device described in patent document 1, if it is determined based on information from the navigation device, it is difficult to determine with high accuracy whether or not the vehicle is traveling in both directions.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2013-190962 (JP 2013-190962A).

Disclosure of Invention

The road recognition device according to an aspect of the present invention includes: a detection unit that detects a road marking of a road on which the host vehicle is traveling; a road marking discriminating unit that discriminates a type of the road marking corresponding to the color and shape of the road marking detected by the detecting unit; and a road determination unit that determines whether or not the road being traveled is a bidirectional traffic road through which bidirectional traffic is performed, based on road marking information including the information on the type of the road marking identified by the road marking identification unit.

Drawings

The objects, features and advantages of the present invention are further elucidated by the following description of embodiments in connection with the accompanying drawings.

Fig. 1 is a block diagram schematically showing the overall configuration of a vehicle control system of an autonomous vehicle having a road recognition device according to an embodiment of the present invention.

Fig. 2 is a diagram showing an example of a driving scenario assumed by the road recognition device according to the embodiment of the present invention.

Fig. 3A is a diagram showing an example of a road marking between the own lane and an adjacent lane, which is different from fig. 2.

Fig. 3B is a view showing another example of the road marking between the own lane and the adjacent lane, which is different from fig. 2.

Fig. 4 is a block diagram showing a main part configuration of the road identifying device according to the embodiment of the present invention.

Fig. 5 is a view showing an example of a road observed from a camera provided in the road recognition device according to the embodiment of the present invention.

Fig. 6 is a flowchart showing an example of processing performed by the controller of fig. 4.

Fig. 7 is a diagram showing an example of a change in the determination result of the road identifying device according to the embodiment of the present invention.

Fig. 8A is a diagram illustrating an example of a road passing on the right side.

Fig. 8B is a diagram showing another example of a road passing on the right side.

Detailed Description

Embodiments of the present invention will be described below with reference to fig. 1 to 8B. The road identifying device according to the embodiment of the present invention is a device for identifying a type of a road, and is applicable to both an autonomous vehicle that is a vehicle having an autonomous function and a manual vehicle that is a vehicle not having an autonomous function. An example of applying the road recognition device to an autonomous vehicle will be described below. The vehicle to which the road recognition device according to the present embodiment is applied may be referred to as a host vehicle, as distinguished from other vehicles.

The host vehicle may be any one of an engine vehicle having an internal combustion engine (engine) as a running drive source, an electric vehicle having a running motor as a running drive source, and a hybrid vehicle having the engine and the running motor as running drive sources.

The vehicle (automated driving vehicle) can travel not only in an automated driving mode in which a driving operation by a driver is not required, but also in a manual driving mode in which a driving operation by a driver is performed. For example, the steering wheel may be operated (manual control is turned on) and the vehicle may be driven in the manual driving mode from a state in which the vehicle is driven in the automatic driving mode without operating the steering wheel (manual control is turned off). Or from a state in which the vehicle is traveling with a predetermined automatic driving level and the manual control is turned off, the automatic driving level may be lowered by 1 level or 2 levels or more in response to a command from the vehicle control system, and the manual control may be turned on.

First, a schematic configuration of automatic driving will be described. Fig. 1 is a block diagram schematically showing the overall configuration of a vehicle control system 100 including a road recognition device according to an embodiment of the present invention. As shown in fig. 1, the vehicle control system 100 mainly includes a controller 10, and an external sensor group 1, an internal sensor group 2, an input/output device 3, a positioning unit 4, a map database 5, a navigation device 6, a communication unit 7, and an actuator AC for traveling, which are communicably connected to the controller 10 via a CAN communication line or the like.

The external sensor group 1 is a generic term for a plurality of sensors (external sensors) that detect peripheral information of the vehicle, that is, external conditions. For example, the external sensor group 1 includes: a laser radar that irradiates laser light to detect the position of an object in the vicinity of the host vehicle (distance from the host vehicle, direction), a radar that irradiates electromagnetic waves to detect the position of an object in the vicinity of the host vehicle, a camera that has an imaging element such as a CCD (charge coupled device) or a CMOS (complementary metal oxide semiconductor) to capture the vicinity of the host vehicle, and the like. Lidar and radar are capable of detecting objects within the field of view of a camera.

The internal sensor group 2 is a generic term for a plurality of sensors (internal sensors) that detect the running 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 of the host vehicle in the front-rear direction and the left-right direction, a rotational speed sensor that detects the rotational speed of the travel drive source, and the like. Sensors that detect driving operations of the driver in the manual driving mode, such as operations on an accelerator pedal, operations on a brake pedal, operations on a steering wheel, and the like, are also included in the internal sensor group 2.

The input/output device 3 is a generic term for devices that input commands from the driver and output information to the driver. The input-output device 3 includes, for example: various switches for a driver to input various instructions by an operation to the operation member, a microphone for a driver to input instructions by voice, a display to provide information to the driver by means of a display image, a speaker to provide information to the driver by voice, and the like.

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 a satellite such as a GPS satellite, a quasi-zenith satellite and the like. The positioning unit 4 measures the current position (latitude, longitude, and altitude) of the vehicle by using the positioning information received by the positioning sensor.

The map database 5 is a device for storing general map information used in the navigation device 6, and is composed of, for example, a hard disk and a semiconductor element. The map information includes: position information of a road, information of a road shape (curvature, etc.), and position information of intersections and intersections. The map information stored in the map database 5 is different from the high-precision map information stored in the storage unit 12 of the controller 10.

The navigation device 6 is a device that searches for a target route on a road that reaches a destination input by a driver, and guides the route along the target route. The input of the destination and the guidance along the target path are performed by the input-output device 3. The target path is calculated based on the current position of the own vehicle measured by the positioning unit 4 and the map information stored in the map database 5. The current position of the vehicle may be measured using the detection value of the external sensor group 1, and the target route may be calculated based on the current position and the map information with high accuracy stored in the storage unit 12.

The communication unit 7 communicates with various servers, not shown, using a network including a wireless communication network typified by the internet, a mobile phone network, and the like, and acquires map information, travel record information, traffic information, and the like from the servers periodically or at any timing. The network includes not only a public wireless communication network but also a closed communication network provided for each prescribed management area, such as a 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, and the map information is updated.

The actuator AC is a travel actuator for controlling travel of the host vehicle. When the travel drive source is an engine, the actuator AC includes a throttle actuator for adjusting the opening degree of a throttle valve of the engine. In the case where the travel drive source is a travel motor, the actuator AC includes the travel motor. A brake actuator for operating a brake device of the vehicle and a steering actuator for driving a steering device are also included in the actuator AC.

The controller 10 is constituted by 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 (read only memory) and a RAM (random access memory), and other peripheral circuits not shown such as an I/O (input/output) interface. Although a plurality of ECUs having different functions such as an engine control ECU, a running motor control ECU, and a brake device ECU may be provided separately, the controller 10 is shown as a collection of these ECUs in fig. 1 for convenience.

The storage unit 12 stores road map information with high accuracy. The road map information includes: the road profile information includes information on the position of a road, information on the shape of the road (curvature, etc.), information on the gradient of the road, information on the positions of intersections, information on the number of lanes, information on the width of a lane, information on the position of each lane (information on the center position of a lane, the boundary line of a lane position), information on the position of a landmark (traffic signal, sign, building, etc.), information on the road profile such as the unevenness of a road surface, etc. The map information stored in the storage unit 12 includes: map information acquired from the outside of the host vehicle through the communication unit 7 and map information created by the host vehicle itself using the detection values of the external sensor group 1 or the detection values of the external sensor group 1 and the internal sensor group 2.

The computing unit 11 has a vehicle position recognition unit 13, an outside recognition unit 14, an action plan generation unit 15, and a travel control unit 16 as functional configurations.

The host vehicle position identifying unit 13 identifies the position of the host vehicle (host vehicle position) on the map based on the position information of the host vehicle acquired by the positioning unit 4 and the map information of the map database 5. The vehicle position can be identified with high accuracy by identifying the vehicle position using the map information stored in the storage unit 12 and the surrounding information of the vehicle detected by the external sensor group 1. When the vehicle position can be measured by using external sensors provided on and beside the road, the vehicle position can be recognized by communicating with the sensors via the communication means 7.

The outside recognition unit 14 recognizes the outside condition around the vehicle from the signal from the external sensor group 1 such as a lidar, a radar, a camera, or the like. For example, the position, speed, acceleration, position, state, etc. of a nearby vehicle (front vehicle, rear vehicle) traveling around the own vehicle, the position of a nearby vehicle that is parked or parked around the own vehicle, and the like are recognized. Other objects include: marks, annunciators, road scores or stop lines of roads, buildings, guardrails, utility poles, billboards, pedestrians, bicycles, and the like. The states of other objects include: the color of the annunciator (red, green, yellow), the speed of movement, orientation, etc. of pedestrians, bicycles.

The action plan generation unit 15 generates a travel track (target track) of the host vehicle from the current time point to the lapse of a predetermined time, for example, based on the target route calculated by the navigation device 6, the map information stored in the storage unit 12, the host vehicle position recognized by the host vehicle position recognition unit 13, and the external situation recognized by the external situation recognition unit 14. When there are a plurality of trajectories on the target path that are candidates for the target trajectory, the action plan generation unit 15 selects an optimal trajectory from among the trajectories that complies with laws and satisfies a criterion such as efficient and safe travel, and takes the selected trajectory as the target trajectory. Then, the action plan generation unit 15 generates an action plan corresponding to the generated target trajectory. The action plan generation unit 15 generates various action plans corresponding to overtaking traveling of the preceding vehicle, lane changing traveling of the changing traveling lane, following traveling of the following preceding vehicle, lane keeping traveling in which the lane is kept without deviating from the traveling lane, decelerating traveling, accelerating traveling, and the like. When generating the target trajectory, the action plan generation unit 15 first determines a travel pattern and generates the target trajectory based on the travel pattern.

In the automatic driving mode, the travel control unit 16 controls each actuator AC to cause the host vehicle to travel along the target trajectory generated by the action plan generation unit 15. More specifically, the travel control unit 16 calculates the required driving force for obtaining the target acceleration per unit time calculated by the action plan generation unit 15 in consideration of the travel resistance determined by the road gradient or the like in the automatic driving mode. Then, for example, feedback control is performed on the actuator AC so that the actual acceleration detected by the internal sensor group 2 becomes the target acceleration. That is, the actuator AC is controlled so that the host vehicle runs at the target vehicle speed and the target acceleration.

In the manual driving mode, the travel control unit 16 controls each actuator AC based on a travel command (steering operation or the like) from the driver acquired by the internal sensor group 2. Even in the manual driving mode, the vehicle may be able to automatically travel under predetermined driving conditions without depending on the driving operation of the driver in a state where the front monitoring obligation by the driver is generated, instead of the full manual driving. For example, in a highway or the like, the own vehicle can travel in a closed manual mode in which the driver releases his/her hand from the steering wheel, that is, in which the own vehicle travels in the same lane by controlling the actuator AC (for example, the steering actuator) by the travel control unit 16 in accordance with the inter-vehicle distance from the preceding vehicle or the like. In addition, even in a state where the automatic driving level is lowered to a predetermined level, the same lane automatic driving can be performed in the automatic driving mode.

The characteristic configuration of the road identifying device according to the embodiment of the present invention will be described on the premise of the above configuration. The road identifying device according to the present embodiment is a device for identifying whether or not a road in traveling is a road type of a bidirectional road. There is a case where a section of bidirectional traffic without a center separation zone exists on an expressway or a general road. In this case, when the host vehicle continues to travel in a state in which the manual control is turned off while continuing to perform a predetermined driving state (for example, the same lane automatic driving), if the host vehicle is approaching the host vehicle and it is necessary to avoid the host vehicle, it is difficult to perform a rapid avoidance operation. Therefore, it is important to identify whether or not a road in running is a two-way traffic for a vehicle that can run with the manual control turned off.

Fig. 2 is a diagram showing an example of a driving scene assumed by the road identifying device according to the present embodiment, and shows a bidirectional traffic road with one lane on one side. In fig. 2, the host vehicle 101 travels in the direction of arrow A1 on the host lane (first lane) LN1, and the other vehicles 102 travel in the direction of arrow A2 opposite to the direction of arrow A1 on the adjacent lane (second lane) LN2 adjacent to the host lane LN 1. The lane LN1 is defined by a pair of left and right road markings L1, L2, and the adjacent lane LN2 is defined by a pair of left and right road markings L3, L4. The road-end-side road markings L1, L4 are white (W) solid lines. The road scribe lines L2, L3 on the center side of the road are solid lines showing yellow (Y) that prohibits out-of-range traffic for overtaking. The road score line L5 in the road center inside the road score lines L2, L3 is a white (W) broken line. The yellow road marking may be orange.

The road marking between the own lane LN1 and the adjacent lane LN2, that is, the boundary between the own lane LN1 and the adjacent lane LN2 is not limited to the example shown in fig. 2, and there are various forms. Fig. 3A, 3B are diagrams showing this example. In fig. 3A, the boundary line between the own lane LN1 and the adjacent lane LN2 is shown by a single road marking L2 (center line). The road marking L2 is indicated by a broken line of white (W). In fig. 3B, a boundary line between the own lane LN1 and the adjacent lane LN2 is shown by a pair of left and right road markings L2, L3. The lane-side road marking L2 is indicated by a white (W) broken line, and the adjacent lane-side road marking L3 is indicated by a yellow (Y) solid line.

In the present embodiment, a road that satisfies a predetermined road marking condition is treated as a bidirectional traffic road. As shown in fig. 2, the road marking condition includes that the road marking L2 on the center line side (adjacent lane side) among the road markings L1, L2 defining the own lane LN1 is yellow. Therefore, the road shown in fig. 3A and 3B does not satisfy the road marking condition, and is therefore not handled as a two-way traffic road. Although not shown, the bidirectional traffic road includes various road marking modes other than the example shown in fig. 2, such as a case where the boundary line between the own lane and the adjacent lane is indicated by a single yellow solid line, a case where the boundary line is indicated by a single yellow solid line and a single white solid line or a broken line in parallel, and the like.

Fig. 4 is a block diagram showing a main part configuration of a road recognition device 50 according to an embodiment of the present invention. As shown in fig. 4, the road recognition device 50 mainly includes a camera 1a, a controller 10, an actuator AC, and a notification unit 3a.

The camera 1a is a single-eye camera having an imaging element (image sensor) such as a CCD (charge coupled device) or a CMOS (complementary metal oxide semiconductor) and capable of recognizing a color of an object, and forms a part of the external sensor group 1 of fig. 1. The camera 1a may be a stereoscopic camera. The camera 1a is mounted at a predetermined position in the front of the host vehicle 101, for example, and continuously captures images of the space in front of the host vehicle 101 and acquires images of objects (camera images). The object includes other vehicles 102 and road markings (e.g., road markings L1 to L5 of fig. 2) on the road. The object may be detected by a laser radar or the like instead of the camera 1a or together with the camera 1 a.

The notification unit 3a is a member for prompting the driver to perform a predetermined driving operation, and forms part of the input/output device 3 of fig. 1. Specifically, the notification unit 3a notifies the driver who turns off the manual control of turning on the manual control when the vehicle 101 is in the same lane automatic driving. The notification unit 3a is constituted by a monitor provided in front of the driver's seat, a speaker in the vehicle interior, and the like.

The controller 10 of fig. 4 has, as a functional configuration assumed by the arithmetic unit 11 (fig. 1), a road marking unit 141 and a road determination unit 142 in addition to the travel control unit 16. The road marking discriminating unit 141 and the road determining unit 142 are configured to discriminate the type of the road marking and the type of the road, respectively, and these are included in the external recognizing unit 14 of fig. 1, for example.

The road marking identifier 141 identifies a plurality of road markings on the road based on the camera image acquired by the camera 1a, and identifies the type of each road marking. That is, whether the color of the road marking is white or yellow, whether the shape of the road marking is a solid line or a broken line, and the like are discriminated. The information of the category of the road marking thus distinguished is taken as road marking information.

The road determination unit 142 determines whether or not the road under travel is a bidirectional traffic road based on the road marking information including the information of the type of the road marking, which is determined by the road marking determination unit 141, and the information of the other vehicle detected by the camera 1 a. Specifically, it is determined whether or not the road under traveling satisfies a predetermined road marking condition, and when the road marking condition is satisfied, it is determined that the road is a bidirectional road. In the following, a bidirectional traffic road with one lane on one side is assumed, and whether or not the bidirectional traffic road is determined.

As shown in fig. 2, the road marking condition includes a road marking L2 (referred to as an R road marking) in which the road marking L2 on the center line side (right side) of the own lane LN1 is specified to be yellow. The road marking condition includes a road marking L1 (referred to as an L road marking) in which a road marking L1 on the opposite side (left side) of the center line of the own lane LN1 is a white solid line. When the R-road score L2 is not recognized, the determination of the bidirectional traffic road cannot be performed.

In the case where the category of the road marking is identified from the camera image, when the L road marking L1 is blurred, it is possible that the L road marking L1 cannot be identified as a white solid line. In view of this, the road marking condition also includes that there is not a sufficient area outside (left side) the L road marking L1. Fig. 5 is a diagram showing an example of a road observed from the camera 1a when the L-road scribe line L1 is blurred and the white solid line is not recognized. As shown in fig. 5, a side wall 103 is erected along the direction in which the road extends on the outside of the L-shaped road marking L1 to divide the road. The boundary line L10 of the road edge, which is the base end portion of the side wall 103, extends substantially in parallel with the R-road scribing line L2.

At this time, the road determination unit 142 sequentially calculates the distance D from the R-road scribing line L2 to the boundary line L10, that is, the distance D from the feature point Pa on the R-road scribing line L2 to the feature point Pb on the boundary line L10, which is recognized by the camera image, along the traveling direction. Then, by determining whether or not the distance D is smaller than the predetermined value D1, it is determined that there is not a sufficient area on the left side of the L-lane line L1, that is, one-sided one-lane. The predetermined value D1 is set to the width of two lanes (e.g., 2×3.5m). Thus, even when the L road marking L1 is not recognized as a white solid line, the road determination unit 142 can satisfactorily determine whether or not the road is a bidirectional road.

Even if the distance D is equal to or greater than the predetermined value D1 (D Σd1), it is not necessarily the left lane of the L-lane line L1. Therefore, a road marking (called LL road marking) that is no longer present outside (left side of) the L road marking L1 is also included in the road marking condition. When the LL road marking is present in the state where D is equal to or greater than D1, the road determination unit 142 determines that the road is not a bidirectional road (non-bidirectional road).

In order to improve the accuracy of determination of the bidirectional traffic, in the present embodiment, the road marking condition includes a case where a predetermined condition is also recognized on the right side of the R road marking L2 from the camera image. Specifically, as shown in fig. 2, a white road scribe line (referred to as RR road scribe line) L5 identified on the outside (right side) of the R road scribe line L2 from the camera image is included in the road scribe line condition.

When the RR road marking L5 is recognized, the road determination unit 142 also determines whether or not there is a vehicle (other vehicle 102) that is traveling on the adjacent lane LN2 and approaching the host vehicle 101 from the front direction, based on the camera image. Then, when the oncoming vehicle is recognized and when the oncoming vehicle is not recognized, the determination result level (the reliability of the determination result) of the two-way traffic road is set to different values. That is, the possibility of being a two-way traffic road is high when there is an oncoming vehicle, and therefore the determination result level is set to be high (two-way traffic (high)), and the determination result level is set to be low (two-way traffic (low)) when there is no oncoming vehicle than when there is an oncoming vehicle.

On the bidirectional traffic road, there is a case where the RR road marking L5 is not detected from the camera image because the RR road marking L5 is not present. In this case, the road determination unit 142 determines whether or not the vehicle is traveling in both directions, based on whether or not the vehicle is traveling in the opposite direction. Specifically, when the opposite vehicle is identified, the possibility of being a two-way traffic road is high, and therefore the road determination unit 142 determines that it is a two-way traffic road (two-way traffic (high)).

On the other hand, when no oncoming vehicle is recognized, the road determination unit 142 determines that the vehicle is a non-bidirectional road (not a bidirectional road). However, even in the case where no opposing vehicle is recognized, there is a possibility of a bidirectional passage road. Therefore, in the case where the oncoming vehicle is not recognized, the road determination section 142 sets the determination result level of the non-bidirectional traffic road to be low (non-bidirectional traffic (low)). When D.gtoreq.D1 and the LL road marking is present, the road determination unit 142 sets the determination result level of the non-bidirectional traffic road to be high (non-bidirectional traffic (high)) as described above.

When the road determination unit 142 determines that the vehicle is a bidirectional road (bidirectional traffic (high) or bidirectional traffic (low)) during the same lane automatic driving, the driving control unit 16 controls the notification unit 3a to output a sound or display prompting the driver to grasp the steering wheel. The travel control section 16 also controls the actuator AC to stop the automatic driving on the same lane of the bidirectional traffic road. In this case, the notification method (notification content) and the actuator control method (for example, timing of the same lane automatic driving suspension) may be made different from each other depending on the bidirectional traffic (high) and the bidirectional traffic (low). When the road determination unit 142 cannot determine that the R-road line L2 is yellow due to a blur or the like of the R-road line L2, the travel control unit 16 outputs a control signal to the actuator AC to prompt the driver to start manual control and to stop the same lane automatic driving.

On the other hand, in the case where the road determination unit 142 determines that the vehicle is traveling on the same lane, the travel control unit 16 controls the actuator AC to continue the same lane automatic driving, when the vehicle is traveling on the non-bidirectional road (high) or non-bidirectional road (low)). When the road determination unit 142 determines that the vehicle is a bidirectional road and instructs to turn on the manual control, the travel control unit 16 outputs a control signal to the notification unit 3a to notify the driver that the manual control can be turned off.

Fig. 6 is a flowchart showing an example of processing performed by the controller of fig. 4. Fig. 6 mainly shows a process of determining a bidirectional traffic road, which is repeatedly performed at a predetermined cycle, for example, starting with the same lane while driving automatically.

As shown in fig. 6, first, in S1 (S: processing step), an image signal from the camera 1a is read. Next, in S2, the category of the road scribe line (R road scribe line, L road scribe line, RR road scribe line, LL road scribe line, etc.) included in the camera image is identified. That is, whether the color of the road marking is white or yellow is determined, whether the shape of the road marking is a solid line or a broken line, and the type of the road marking is identified. Next, in S3, it is determined whether or not the R-road marking L2 on the right side of the own lane LN1 is yellow. S4 is entered when S3 is negative (S3: NO), and S5 is entered when S3 is positive (S3: yes). In S4, the process ends after the determination that the bidirectional traffic is not possible.

In S5, it is determined whether or not the L-lane line L1 on the left side of the own lane LN1 is a white solid line. If S5 is affirmative (S5: yes), the routine proceeds to S6, where it is determined whether or not the RR road marking L5 on the right side of the R road marking L2 is white. When S6 is affirmative (S6: yes), S7 is entered, and it is determined whether or not a vehicle is present. S8 is entered when S7 is affirmative (S7: yes), and S9 is entered when negative (S7: no). In S8, the two-way traffic road (two-way traffic (high)) is determined at a high determination result level, and the process ends. In S9, the two-way traffic road (two-way traffic (low)) is determined at a low determination result level, and the process ends.

In S6, when it is determined that the RR lane line L5 is not white, S6 is negative (S6: NO) and S10 is entered. In S10, it is determined whether or not a vehicle is present as in S7. S8 is entered when S10 is affirmative (S10: yes), and S11 is entered when negative (S10: no). In S11, the non-bidirectional traffic road (non-bidirectional traffic (low)) is determined at a low determination result level, and the process ends.

In S5, when it is determined that the L-lane line L1 is not a white solid line, S5 is negative (S5: NO) and S12 is entered. In S12, it is determined whether or not there is a sufficient area in the adjacent lane on the left side of the own lane LN 1. That is, as shown in fig. 5, the distance D from the R road marking L2 to the boundary line L10 of the road is calculated from the camera image, and it is determined whether or not the distance D is equal to or greater than the predetermined value D1. When S12 is affirmative (S12: yes), S13 is entered, and when negative (S12: no), S6 is entered. In S13, it is determined whether or not a lane marking (LL lane marking) is still present on the left side of the L lane marking L1. When S13 is affirmative (S13: yes), S14 is entered, and when negative (S13: no) is entered, S6 is entered. At S14, the non-bidirectional traffic road (non-bidirectional traffic (high)) is determined at a high determination result level, and the process ends.

More specifically, the operation of the road identifying device 50 of the present embodiment will be described. As shown in fig. 2, the R road marking L2 (first road marking) on the right side (opposite lane side) of the own lane LN1 is yellow (for example, a solid yellow line), the L road marking L1 on the left side (second road marking) is a solid white line, the RR road marking L5 on the right side of the R road marking L2 is white (for example, a broken white line), and when the opposite vehicle (other vehicle 102) is recognized by the adjacent lane LN2, all the multiple road marking conditions are satisfied, and therefore it is determined that the road is a bidirectional traffic road (bidirectional traffic (high)) (S8). As described above, it is possible to determine whether or not the road is a bidirectional road more accurately, not only by specifying the types of the road scores L1 and L2 of the own lane LN1, but also by considering the type of the RR road score L5 and the presence or absence of the oncoming vehicle. When the host vehicle 101 determines that the vehicle is on a bidirectional road during the same-lane automatic driving, the driver is instructed to turn on the manual control via the notification unit 3a, that is, the driver is alerted to turn on the manual control via the monitor and the speaker, and the same-lane automatic driving is stopped. This allows the manual control to be started at an appropriate timing and the same lane automatic driving to be stopped, thereby improving the running safety of the automatically driven vehicle.

Even in a bidirectional traffic road, the road marking condition that the oncoming vehicle (other vehicle) 102 exists may not be satisfied. In this case, when the road marking condition that the R road marking L2 is yellow and the L road marking L1 is a solid line of white is satisfied, it is determined that the road is a bidirectional traffic road (bidirectional traffic (low)) (S9). Thus, when the road marking condition partially necessary is satisfied, the road is determined to be a bidirectional traffic road even if all the road marking conditions are not satisfied, and the bidirectional traffic road corresponding to various road structures can be determined. In this case, the determination result level is set to be lower than the case where all the road marking conditions are satisfied, so that an appropriate determination can be made regarding the bidirectional traffic road.

The L road scribe line L1 of the white solid line may not be recognized from the camera image due to blurring or the like of the L road scribe line L1. In this case, when the distance D from the R-road score line L2 to the boundary line L10 (fig. 5) at the left end of the road is smaller than the predetermined value D1 (s12→s6), it is determined that the road is a bidirectional traffic road because no adjacent lane exists on the left side of the own lane LN1 (S8, S9). Even when the distance D is equal to or greater than the predetermined value D1 and the LL road score is not recognized on the left side of the L road score L1 (s13→s6), the adjacent lane is not present on the left side of the own lane LN1, and the bidirectional traffic road is determined (S8, S9). Thus, even when the L-road score L1 is not recognized, it is possible to satisfactorily determine whether or not the road is a bidirectional road.

In the above, when it is determined that the road marking condition is satisfied, it is determined that the road is a bidirectional traffic road, but the camera 1a may erroneously detect a road marking (for example, an R road marking L2) due to backlight or the like, and in this case, the determination of bidirectional traffic may be erroneous. Therefore, in the case where it is determined that the road is not a bidirectional road, the road determination unit 142 may determine that the road is a bidirectional road when the road marking condition is satisfied for a predetermined time or longer. In the case where the road marking condition is not satisfied for a predetermined time or longer in the state where the road is determined to be a bidirectional road, the road determination unit 142 may determine that the road is not a bidirectional road. That is, the predetermined state may be added to the determination condition of the bidirectional traffic road for a predetermined time.

Fig. 7 is a diagram showing an example of a change in the result of the determination of the bidirectional traffic road by the road identifying device 50 configured in consideration of this point over time. Fig. 7 shows an example of the change in the determination result after the road determination unit 142 determines that the road is a bidirectional road (example 1) and a comparative example thereof (comparative example 1), and an example of the change in the determination result after the road determination unit determines that the road is a bidirectional road (example 2) and a comparative example thereof (comparative example 2). In the figure, the case where it is determined that the road is a bidirectional road is shown by hatching.

As shown in fig. 7, in example 1, even if the road marking condition is satisfied at time t1, the road determination unit 142 does not immediately determine that the road is a bidirectional road, and at time t2, the road determination unit determines that the road is a bidirectional road when a predetermined time Δt1 (for example, 2 seconds) has elapsed after the road marking condition is satisfied. Then, at time t3, when the road marking condition is not satisfied, it is immediately determined that the road is a non-bidirectional road in comparative example 1. In contrast, in embodiment 1, even if the road marking condition is not satisfied, the road is not immediately determined to be a non-bidirectional road, and when the state in which the road marking condition is not satisfied continues to a time point t4 after a predetermined time Δt2 (for example, 20 seconds), the road determination unit 142 determines the road to be a non-bidirectional road. Therefore, as shown in embodiment 1 of fig. 7, as long as the duration of the non-establishment of the road marking condition is less than the prescribed time Δt2, the determination of the bidirectional traffic road is kept unchanged.

Thus, for example, when the host vehicle 101 travels under a condition such as backlight, it is possible to prevent erroneous detection of a yellow road marking as a white road marking and erroneous determination of a non-bidirectional road. That is, since there is a low possibility that the false detection by the backlight continues for the predetermined time Δt2 or longer, the road determination unit 142 can accurately determine the change from the bidirectional traffic road to the non-bidirectional traffic road by making the road marking condition not to be satisfied for the predetermined time Δt2 or longer as the determination condition.

In comparative example 2, in the state of traveling on the road determined to be non-bidirectional traffic, at time t5, when it is determined that the road marking condition is satisfied, it is immediately determined to be bidirectional traffic. In contrast, in example 2, even if the road marking condition is determined to be satisfied by the road determination unit 142, it is not immediately determined that the road is a bidirectional traffic road, and when the state in which the road marking condition is satisfied continues until a time point t6 after the predetermined time Δt1, it is determined that the road is a bidirectional traffic road. Therefore, as shown in embodiment 2 of fig. 7, as long as the duration for which the road marking condition is established is less than the prescribed time Δt1, the determination of the non-bidirectional traffic road remains unchanged.

In this way, when the road marking condition is temporarily established due to the false detection by the camera 1a, the road determination unit 142 can be prevented from erroneously determining that the road is a bidirectional traffic road, and a change from a non-bidirectional traffic road to a bidirectional traffic road can be accurately determined. Here, since the predetermined time Δt2 is set to be longer than the predetermined time Δt1, it is not easy to determine that the road is a bidirectional road as compared with the case where the road is determined to be a bidirectional road. Therefore, it is possible to satisfactorily prevent the same lane from being driven automatically on the bidirectional road, which is assumed to be a non-bidirectional road, and the like, and the safety is high.

The present embodiment can provide the following effects.

(1) The road recognition device 50 includes: a camera 1a that detects a road marking of a road on which the host vehicle 101 is traveling; a road marking discriminating unit 141 for discriminating the type of the road marking corresponding to the color and shape of the road marking detected by the camera 1 a; and a road determination unit 142 that determines whether or not the road under travel is a bidirectional traffic road (fig. 4) that performs bidirectional traffic, based on road marking information including the information of the type of road marking identified by the road marking identification unit 141. In the bidirectional traffic road, the color and shape of the road marking around the own lane LN1 are prescribed. Therefore, by determining whether or not the road is a bidirectional traffic road based on the color and shape of the road marking detected by the camera 1a, an accurate determination can be made.

(2) The camera 1a is configured to be able to detect another vehicle 102 that is a counter vehicle traveling in a counter lane (adjacent lane) LN 2. The road determination unit 142 also determines whether or not the road in which the vehicle is traveling is a bidirectional traffic road based on whether or not the opposite vehicle 102 is detected by the camera 1a (fig. 6). In this way, by taking into consideration whether the oncoming vehicle 102 is actually detected, it is possible to more accurately determine whether it is a bidirectional traffic road.

(3) The road determination unit 142 determines whether or not the road being traveled is a bidirectional traffic road based on information defining the type of the pair of left and right road markings L1, L2 of the own lane LN1 in which the own vehicle 101 is traveling (fig. 6). That is, a solid line in which the R road marking L2 is yellow and the L road marking L1 is white is included in the road marking condition, and whether or not the road is a bidirectional traffic road is determined based on whether or not the road marking condition is satisfied. Thus, it is possible to satisfactorily determine whether or not a bidirectional traffic road is present, taking into account the color and shape of the road marking.

(4) The road determination unit 142 also determines whether or not the road under travel is a bidirectional traffic road based on the length (distance D) in the vehicle width direction of the area outside the own lane LN1 (fig. 6). That is, the distance D is smaller than the predetermined value D1 and included in the road marking condition, and whether or not the road is a bidirectional traffic road is determined based on whether or not the road marking condition is satisfied. In this way, even when the L road marking L1 is not determined to be a white solid line, for example, when the L road marking L1 is blurred, it is possible to satisfactorily determine whether or not the road is a bidirectional road.

(5) The road determination unit 142 also determines whether or not the driving lane is a bidirectional traffic road based on information on the outside of the lane lines L1, L2 defining the own lane LN1, for example, the LL lane line and the RR lane line L5 (fig. 6). Thus, it is possible to more accurately determine whether or not the road in running is a bidirectional traffic road.

(6) The road determination unit 142 determines whether or not the road marking condition is satisfied based on the road marking information, and determines that the road being traveled is a bidirectional traffic road when it is determined that the road marking condition is satisfied. On the other hand, after the road is determined to be a bidirectional traffic road, when it is determined that the road marking condition is not satisfied for a predetermined time (first predetermined time) Δt2 or longer, it is determined that the road in running is not a bidirectional traffic road (fig. 7). Thus, even when the camera 1a erroneously detects the type of the road marking due to backlight or the like, it is possible to accurately determine the bidirectional traffic road.

(7) After determining that the road under traveling is not a bidirectional traffic road, the road determination unit 142 determines that the road under traveling is a bidirectional traffic road when it determines that the road marking condition is satisfied for a predetermined time (second predetermined time) Δt1 or longer that is shorter than the predetermined time Δt2 (fig. 7). Thus, it can be accurately and quickly determined that the road is a bidirectional traffic road.

The above-described embodiments can be modified into various modes. Several modifications will be described below. In the above embodiment, the camera 1a detects the road marking and the opposite vehicle of the road in running, but the road marking and the opposite vehicle may be detected by different detecting units. In the above embodiment, the R road marking L2 is yellow (predetermined first category) and the L road marking L1 is a white solid line (predetermined second category) included in the road marking condition, and it is determined whether or not the road is a bidirectional road. However, in the bidirectional traffic road, the type of the pair of left and right road markings L1, L2 defining the own lane LN1 may be different depending on the country. Therefore, it is also possible to determine whether or not the road is a two-way traffic road in consideration of the criterion of the two-way traffic road of each country. Therefore, the manner in which the road determination unit determines the bidirectional traffic road based on the information on the type of the pair of right and left road markings is not limited to the above.

In the above embodiment, the example of the road passing on the left side is shown, but the present invention can be applied to the road passing on the right side as well. Fig. 8A and 8B are diagrams showing an example of a non-bidirectional road passing on the right side, and are examples of roads in the united states. In fig. 8A, yellow road markings L11, L12 are present on the left side of the own lane LN 1. In this way, the L road marking and the LL road marking may be yellow, and the road determination unit may determine whether or not the road is a non-bidirectional road. In fig. 8B, the left side of the lane LN1 is a yellow road marking L11, and the right side is a white road marking L13, which is a broken line. In the above embodiment, it is determined whether the road is a two-way traffic road with a single lane, but it may be determined whether the road is a two-way traffic road with a plurality of lanes in the same manner as described above.

In the above embodiment, the road determination unit 142 determines whether or not the road under traveling is a bidirectional traffic road based on the length (distance D) in the vehicle width direction of the area outside the own lane LN1 and based on the information of the type of the road marking outside the pair of left and right road markings L1, L2, but the road determination unit may be configured in any manner as long as it determines whether or not the road under traveling is a bidirectional traffic road that makes bidirectional traffic based on the road marking information including the information of the type of the road marking identified by the road marking identification unit. In the above embodiment, the road determination unit 142 determines that the road in running is not a bidirectional traffic road when it is determined that the predetermined road condition is not satisfied for the predetermined time Δt2 or longer after the bidirectional traffic road is determined, but the condition that the predetermined time is not continued may be omitted.

In the above-described embodiment, the example in which the road recognition device 50 is applied to the automatically driven vehicle has been described, but the present invention can be similarly applied to a manually driven vehicle having a driving support function.

One or more of the above embodiments and modifications may be arbitrarily combined, or the modifications may be combined with each other.

By adopting the method and the device, whether the road in running is a bidirectional traffic road can be accurately judged.

While the invention has been described in connection with preferred embodiments, it will be understood by those skilled in the art that various modifications and changes can be made without departing from the scope of the disclosure of the following claims.

Claims (10)

1. A road recognition device is characterized by comprising:

a detection unit (1 a) that detects a road marking of a road on which the host vehicle (101) is traveling;

a road marking discriminating unit (141) for discriminating the type of the road marking corresponding to the color and shape of the road marking detected by the detecting unit (1 a); and

and a road determination unit (142) that determines whether or not the road being traveled is a bidirectional traffic road that is in bidirectional traffic, based on road marking information including the information on the type of road marking that is determined by the road marking determination unit (141).

2. The road recognition apparatus according to claim 1, wherein,

the detection unit (1 a) is configured to be able to detect an oncoming vehicle (102),

the road determination unit (142) also determines whether or not the road being traveled is a bidirectional road based on whether or not the opposite vehicle (102) has been detected by the detection unit (1 a).

3. The road recognition apparatus according to claim 1 or 2, wherein,

the road determination unit (142) determines whether or not the road being traveled is a bidirectional road, based on information defining the type of a pair of left and right road markings (L1, L2) of the own lane (LN 1) in which the own vehicle (101) is traveling.

4. The road recognition apparatus according to claim 3, wherein,

the road determination unit (142) also determines whether or not the road being traveled is a bidirectional road, based on the length (D) in the vehicle width direction of the area outside the own lane (LN 1).

5. The road recognition apparatus according to claim 4, wherein,

a pair of right and left road markings defining the own lane (LN 1) are a first road marking (LN 2) on the opposite lane side and a second road marking (LN 1) on the opposite lane side,

the road determination unit (142),

When the category of the first road marking (L2) is a predetermined first category and the category of the second road marking (L1) is a predetermined second category, the road in running is determined to be a bidirectional traffic road regardless of the length (D) in the vehicle width direction of the area outside the own lane,

when the category of the first road marking (L2) is the predetermined first category and the category of the second road marking (L1) is not the predetermined second category, the road in running is determined to be a bidirectional traffic road as long as the length (D) in the vehicle width direction of the area outside the own lane is smaller than a predetermined value (D1).

6. The road recognition apparatus according to claim 3, wherein,

the road determination unit (142) also determines whether or not the road being traveled is a bidirectional road based on information on the type of the road marking outside the pair of left and right road markings (L1, L2).

7. The road recognition apparatus according to claim 1 or 2, wherein,

the road determination unit (142) determines whether or not a predetermined road condition is satisfied based on the road marking information, determines that the road under travel is a bidirectional traffic road when the predetermined road condition is determined to be satisfied, and determines that the road under travel is not a bidirectional traffic road when the predetermined road condition is not satisfied for a predetermined time (Deltat 2) or longer after the road is determined to be a bidirectional traffic road.

8. The road recognition apparatus according to claim 7, wherein,

the prescribed time (deltat 2) is a first prescribed time,

the road determination unit (142) determines that the road in running is a bidirectional road when it is determined that the predetermined road condition is satisfied for a second predetermined time (Deltat1) shorter than the first predetermined time (Deltat2) or longer after it is determined that the road in running is not a bidirectional road.

9. The road recognition apparatus according to claim 1 or 2, further comprising a travel control unit (16), wherein the travel control unit (16) controls the steering actuator so that the same lane is automatically driven by the same lane without depending on the operation of the driver,

when the road determination unit (142) determines that the road being driven is a bidirectional road while the vehicle is driving in the same lane, the driving control unit (16) controls the steering actuator so that the same lane driving is stopped.

10. The road recognition apparatus according to claim 9, further comprising a notification unit (3 a), wherein the notification unit (3 a) notifies the driver of information,

When the road determination unit (142) determines that the road being traveled is a bidirectional road when the vehicle is traveling in the same lane by autonomous driving, the travel control unit (16) controls the notification unit (3 a) to notify the information of the grip of the steering wheel.