Driving assistance system

Abstract

To provide a travel support system capable of achieving automatic drive adaptable to travel on many routes.SOLUTION: A travel support system 1 is a system for driving an automatic drive vehicle 10 in automatic drive, and includes an automatic drive disabled section determination unit 39 and a following travel unit 41. The automatic drive disabled section determination unit 39 determines whether or not there is an automatic drive disabled section in which travel by automatic drive of the automatic drive vehicle 10 is not possible on a route of automatic drive of the automatic drive vehicle 10. When it is determined that there is the automatic drive disabled section, the following travel unit 41 controls travel of the automatic drive vehicle 10 so as to follow a reinforcing vehicle capable of traveling the automatic drive disabled section in the automatic drive disabled section.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a driving assistance system. [Background technology]

[0002] As a technique relating to a driving assistance system, Patent Document 1 discloses a vehicle control device that causes an inoperable vehicle, the driver of which has become unable to drive, to automatically follow a leading vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-108860 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when a vehicle is driven autonomously, there may be a situation where the vehicle must be driven along a route including a section where autonomous driving is not possible. However, the driving assistance system does not adequately handle such a situation, and it is difficult to drive the vehicle autonomously along the route. It is still difficult for the driving assistance system to realize autonomous driving that is compatible with many routes.

[0005] Therefore, an object of the present invention is to provide a driving assistance system that can realize automatic driving compatible with driving on many routes. [Means for solving the problem]

[0006] A driving assistance system according to one embodiment of the present invention is a driving assistance system that drives a first vehicle in an autonomous driving manner, and includes a determination unit that determines whether or not there is an autonomous driving incapable section on the autonomous driving route of the first vehicle, where the first vehicle cannot drive autonomously, and a following driving unit that controls the driving of the first vehicle so that the first vehicle follows a second vehicle that is capable of traversing the autonomous driving incapable section, if the determination unit determines that there is a section where autonomous driving is not possible, in the autonomous driving incapable section.

[0007] In this driving assistance system, when the first vehicle drives autonomously along a route that includes a section where autonomous driving is not possible, the first vehicle drives in a manner that follows the second vehicle in the section where autonomous driving is not possible. This makes it possible to drive the first vehicle autonomously along a route that includes a section where autonomous driving is not possible. This makes it possible to realize autonomous driving that is compatible with driving on many routes.

[0008] In the driving assistance system according to an aspect of the present invention, the determination unit may determine a specific section on a route where a performance required for autonomous driving exceeds a predetermined value as an autonomous driving incapable section. In this case, the autonomous driving incapable section can be determined by using the performance required for autonomous driving of the route.

[0009] In the driving assistance system according to an aspect of the present invention, the predetermined value may be set based on the autonomous driving performance of the first vehicle. In this case, the predetermined value can be set by utilizing the autonomous driving performance of the first vehicle.

[0010] In the driving assistance system according to one aspect of the present invention, the second vehicle may be a vehicle that travels only in a predetermined section including an area where autonomous driving is not possible. In this case, it is possible to specialize the second vehicle in traveling in the predetermined section including the area where autonomous driving is not possible.

[0011] A driving assistance system according to an aspect of the present invention may include a vehicle allocation and merging unit that, when the determining unit determines that there is an area where automatic driving is not possible, requests the dispatch of a second vehicle to a merging area between the current position of the first vehicle and the area where automatic driving is not possible, and causes the first vehicle to drive to the merging area. In this case, when the following driving unit performs following driving, the first vehicle and the second vehicle can be efficiently merged. Effect of the Invention

[0012] According to the present invention, it is possible to provide a driving assistance system that can realize automatic driving compatible with driving on many routes. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a block diagram showing the configuration of a driving assistance system according to an embodiment. [Diagram 2] FIG. 2 is a flowchart showing an example of autonomous driving performed by the driving assistance system according to the embodiment. [Diagram 3] Fig. 3(a) is a schematic overhead view illustrating an example of autonomous driving performed by a driving assistance system according to an embodiment. Fig. 3(b) is a schematic overhead view showing a continuation of Fig. 3(a). Fig. 3(c) is a schematic overhead view showing a continuation of Fig. 3(b). [Figure 4] Fig. 4(a) is a schematic overhead view showing a continuation of Fig. 3(c), Fig. 4(b) is a schematic overhead view showing a continuation of Fig. 4(a), and Fig. 4(c) is a schematic overhead view showing a continuation of Fig. 4(b). [Diagram 5] FIG. 5 is a block diagram showing a configuration of a driving assistance system according to a modified example. [Figure 6] FIG. 6 is a block diagram showing the configuration of a driving assistance system according to another modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are designated by the same reference numerals, and duplicated description will be omitted.

[0015] FIG. 1 is a block diagram showing the configuration of a driving assistance system 1. The driving assistance system 1 shown in FIG. 1 is a system that drives a first vehicle in an autonomous driving manner. Hereinafter, the first vehicle that is the subject of autonomous driving is referred to as an autonomous driving vehicle 10. The autonomous driving vehicle 10 is a vehicle capable of autonomous driving. The autonomous driving vehicle 10 is a vehicle that does not require driving operation by a driver and is capable of autonomous driving control. The autonomous driving vehicle 10 includes a remote support compatible vehicle that can perform autonomous driving in accordance with remote support by a remote operator. The remote operator is a person who provides remote support to the autonomous driving vehicle 10. The remote support is an instruction from the remote operator regarding the driving of the autonomous driving vehicle 10. The number of remote operators may be one or more.

[0016] As shown in FIG. 3, the driving assistance system 1 has an automatic driving ECU 30. The automatic driving ECU 30 is an electronic control unit having a processor such as a CPU [Central Processing Unit] and memories such as a ROM [Read Only Memory] and a RAM [Random Access Memory]. In the automatic driving ECU 30, for example, a program recorded in the ROM is loaded into the RAM, and the program loaded into the RAM is executed by the CPU, thereby realizing various functions. The automatic driving ECU 30 may be composed of a plurality of electronic control units. The automatic driving ECU 30 is mounted on an automatic driving vehicle 10. The automatic driving ECU 30 is connected to a GPS [Global Positioning System] receiver 21, an external sensor, an internal sensor 23, a map database 24, a communication unit 25, and an actuator 26.

[0017] The GPS receiver 21 receives signals from three or more GPS satellites to measure the position of the autonomously driven vehicle 10 (for example, the latitude and longitude of the autonomously driven vehicle 10). The GPS receiver 21 transmits the measured position information of the autonomously driven vehicle 10 to the autonomous driving ECU 30.

[0018] The external sensor 22 is an on-board sensor that detects the external environment of the autonomous vehicle 10. The external sensor 22 includes at least a camera. The camera is an imaging device that captures an image of the external environment of the autonomous vehicle 10. The external sensor 22 may include a radar sensor. The radar sensor is a detection device that detects objects around the autonomous vehicle 10 using radio waves (e.g., millimeter waves) or light. The radar sensor includes, for example, millimeter wave radar or LIDAR (Light Detection and Ranging). The radar sensor detects an object by transmitting radio waves or light to the periphery of the autonomous vehicle 10 and receiving the radio waves or light reflected by the object. The external sensor 22 may include a sonar sensor that detects sounds outside the autonomous vehicle 10.

[0019] The internal sensor 23 is an in-vehicle sensor that detects the traveling state of the autonomous vehicle 10. The internal sensor 23 includes a vehicle speed sensor, an acceleration sensor, and a yaw rate sensor. The vehicle speed sensor is a detector that detects the speed of the autonomous vehicle 10. The acceleration sensor is a detector that detects the acceleration of the autonomous vehicle 10. The acceleration sensor includes, for example, a longitudinal acceleration sensor that detects the acceleration in the longitudinal direction of the autonomous vehicle 10. The acceleration sensor may include a lateral acceleration sensor that detects the lateral acceleration of the autonomous vehicle 10. The yaw rate sensor is a detector that detects the yaw rate (rotational angular velocity) around the vertical axis of the center of gravity of the autonomous vehicle 10. As the yaw rate sensor, for example, a gyro sensor can be used.

[0020] The map database 24 is a database that records map information. The map database 24 is formed in a recording device such as a hard disk drive (HDD) mounted on the autonomous vehicle 10. The map information includes, for example, road position information, road shape information (for example, curvature information), and intersection and branch point position information. The map information may include traffic regulation information such as a legal maximum speed associated with the position information. The map information may include landmark information used to acquire the position information of the autonomous vehicle 10. Examples of landmarks that can be used include road signs, road markings, traffic lights, utility poles, and the like. The map information may include bus stop position information. The map database 24 may be configured in a server that can communicate with the autonomous vehicle 10.

[0021] The communication unit 25 is a communication device that controls wireless communication with the outside of the autonomous driving vehicle 10. The communication unit 25 performs road-to-vehicle communication and vehicle-to-vehicle communication. The communication unit 25 may communicate various information with a server via a communication network. The communication unit 25 is not particularly limited, and various known communication devices can be used.

[0022] The actuator 26 is a device used to control the autonomous vehicle 10. The actuator 26 includes at least a drive actuator, a brake actuator, and a steering actuator. The drive actuator controls the amount of air supplied to the engine (throttle opening) in response to a control signal from the autonomous driving ECU 30, thereby controlling the driving force of the autonomous driving vehicle 10. When the autonomous driving vehicle 10 is a hybrid vehicle, in addition to the amount of air supplied to the engine, a control signal from the autonomous driving ECU 30 is input to a motor serving as a power source to control the driving force. When the autonomous driving vehicle 10 is an electric vehicle, a control signal from the autonomous driving ECU 30 is input to a motor serving as a power source to control the driving force. The motor serving as a power source in these cases constitutes the actuator 26.

[0023] The brake actuator controls a brake system in response to a control signal from the autonomous driving ECU 30, and controls the braking force applied to the wheels of the autonomous driving vehicle 10. For example, a hydraulic brake system can be used as the brake system. The steering actuator controls the drive of an assist motor that controls the steering torque of the electric power steering system in response to a control signal from the autonomous driving ECU 30. In this way, the steering actuator controls the steering torque of the autonomous driving vehicle 10.

[0024] The following describes the functional configuration of the autonomous driving ECU 30. The autonomous driving ECU 30 has a vehicle position acquisition unit 32, an external environment recognition unit 33, a driving state recognition unit 34, a route generation unit 37, an autonomous driving control unit 38, an autonomous driving incapable section determination unit 39, a vehicle dispatch merging unit 40, and a following driving unit 41. Some of the functions of the autonomous driving ECU 30 may be executed by a server capable of communicating with the autonomous driving vehicle 10.

[0025] The vehicle position acquisition unit 32 acquires position information (position on the map) of the autonomous vehicle 10 based on the position information of the GPS receiver 21 and the map information of the map database 24. The vehicle position acquisition unit 32 may acquire the position information of the autonomous vehicle 10 by SLAM [Simultaneous Localization and Mapping] technology using target information included in the map information of the map database 24 and the detection result of the external sensor 22. The vehicle position acquisition unit 32 may recognize the lateral position of the autonomous vehicle 10 with respect to the lane (the position of the autonomous vehicle 10 in the lane width direction) from the positional relationship between the lane markings and the autonomous vehicle 10, and include it in the position information. The vehicle position acquisition unit 32 may acquire the position information of the autonomous vehicle 10 by other well-known methods.

[0026] The external environment recognition unit 33 recognizes the external environment of the autonomous vehicle 10 based on the detection result of the external sensor 22. The external environment includes the relative positions of surrounding objects with respect to the autonomous vehicle 10. The external environment may include the relative speed and movement direction of surrounding objects with respect to the autonomous vehicle 10. The external environment may include types of objects such as other vehicles, pedestrians, and bicycles. The types of objects can be identified by well-known methods such as pattern matching. The external environment may include the results of lane marking recognition (white line recognition) around the autonomous vehicle 10. The external environment may include the recognition results of the lighting state of a traffic light. For example, the external environment recognition unit 33 can recognize the lighting state of a traffic light in front of the autonomous vehicle 10 (whether the lighting state is for passing or for prohibiting passing, etc.) based on an image from the camera of the external sensor 22.

[0027] The driving state recognition unit 34 recognizes the driving state of the autonomously driven vehicle 10 based on the detection result of the internal sensor 23. The driving state includes the speed of the autonomously driven vehicle 10, the acceleration of the autonomously driven vehicle 10, and the yaw rate of the autonomously driven vehicle 10. Specifically, the driving state recognition unit 34 recognizes the speed of the autonomously driven vehicle 10 based on vehicle speed information from a vehicle speed sensor. The driving state recognition unit 34 recognizes the acceleration of the autonomously driven vehicle 10 based on vehicle speed information from an acceleration sensor. The driving state recognition unit 34 recognizes the orientation of the autonomously driven vehicle 10 based on yaw rate information from a yaw rate sensor.

[0028] The trajectory generation unit 37 generates a trajectory to be used for the autonomous driving of the autonomous vehicle 10. The trajectory generation unit 37 generates a trajectory for autonomous driving based on the route along which the autonomous vehicle 10 travels, map information, position information of the autonomous vehicle 10, the external environment of the autonomous vehicle 10, and the driving state of the autonomous vehicle 10. The trajectory corresponds to a driving plan for autonomous driving. The trajectory includes a path along which the vehicle travels in autonomous driving and a vehicle speed plan for autonomous driving. The trajectory is a planned trajectory along which the vehicle travels in autonomous driving on the route. The trajectory can be, for example, data of steering angle changes (steering angle plan) of the autonomous vehicle 10 according to the position on the route. The position on the route is, for example, a set vertical position set at a predetermined interval (for example, 1 m) in the traveling direction of the route. The steering angle plan is data in which a target steering angle is associated with each set vertical position.

[0029] The course generation unit 37 generates a route for the autonomous vehicle 10 to travel on, for example, based on the route, map information, the external environment of the autonomous vehicle 10, and the travel state of the autonomous vehicle 10. The course generation unit 37 generates a route such that the autonomous vehicle 10 passes through the center (center in the lane width direction) of the lane included in the route. The vehicle speed plan is data in which a target vehicle speed is associated with each set longitudinal position, for example. The set longitudinal position may be set based on the travel time of the autonomous vehicle 10, rather than the distance. The set longitudinal position may be set as the destination position of the vehicle one second later, or the destination position of the vehicle two seconds later, for example. In this case, the vehicle speed plan can also be expressed as data according to the travel time.

[0030] The route generation unit 37 generates a vehicle speed plan based on traffic regulation information such as the legal maximum speed included in the route and map information. A speed preset for a position or section on the map may be used instead of the legal maximum speed. The route generation unit 37 generates a route for autonomous driving from the route and the vehicle speed plan. Note that the route generation method in the route generation unit 37 is not limited to the above-mentioned content, and any well-known method related to autonomous driving may be adopted. The same applies to the content of the route.

[0031] The autonomous driving control unit 38 executes autonomous driving of the autonomous vehicle 10. The autonomous driving control unit 38 executes autonomous driving of the autonomous vehicle 10, for example, based on the external environment of the autonomous vehicle 10, the driving state of the autonomous vehicle 10, and the route generated by the route generation unit 37. The autonomous driving control unit 38 executes autonomous driving of the autonomous vehicle 10 by sending a control signal to the actuator 26.

[0032] The automatic driving incapable section determination unit 39 is a determination unit that determines whether or not there is an automatic driving incapable section on the route along which the automatic driving vehicle 10 travels in automatic driving (hereinafter, simply referred to as the "route"). The route here is included in the route generated by the route generation unit 37. The automatic driving incapable section is a section in which the automatic driving vehicle 10 cannot travel by automatic driving (autonomous driving). The automatic driving incapable section is a section outside the operational design domain, which is the driving environment condition that is the premise for the operation of the system related to automatic driving in the design. For example, the automatic driving incapable section is a section that is outside the operational design domain due to dynamic factors such as a sudden change in weather or congestion, construction work, or an accident of another traffic participant. For example, the automatic driving incapable section is a construction section, a lane restriction section due to an accident, a right turn in rainy weather, and a section where lane changes are required in rainy weather or under congestion. The automatic driving incapable section determination unit 39 extracts the automatic driving incapable section on the route. The autonomous driving incapable section determination unit 39 includes two elements: an autonomous driving travel evaluation unit and a route requirement performance evaluation unit.

[0033] The autonomous driving evaluation unit evaluates the autonomous driving performance of the autonomous vehicle 10. For example, the autonomous driving evaluation unit performs a static evaluation to determine whether or not advanced judgments such as flag recognition in a construction zone can be made, and a dynamic evaluation to evaluate the distance of an object that can actually be recognized during autonomous driving to evaluate the recognition range. The recognition range tends to be smaller in rainy weather than in sunny weather. The autonomous driving evaluation unit sets a predetermined value that represents the autonomous driving performance of the autonomous vehicle 10, which is an index for determining whether or not an area is an area where autonomous driving is not possible, based on the autonomous driving performance of the autonomous vehicle 10. For example, the autonomous driving evaluation unit sets the predetermined value so that the value becomes larger as the autonomous driving performance of the autonomous vehicle 10 becomes better.

[0034] The route required performance evaluation unit evaluates the performance required for autonomous driving in each section on the route based on the map database 24, etc. For example, the route required performance evaluation unit evaluates a construction section on the route as requiring advanced situation judgment capability, and sets a required performance evaluation value according to the evaluation. For example, the route required performance evaluation unit evaluates a section on the route where an intersection is passed through by turning right as requiring forward measurement performance of a specified length, and sets a required performance evaluation value according to the evaluation. For example, the route required performance evaluation unit evaluates a lane change section on the route as requiring rear side measurement performance of a specified length in order to safely change lanes, and sets a required performance evaluation value according to the evaluation.

[0035] The automatic driving incapable section determination unit 39 searches for a specific section on the route whose required performance evaluation value exceeds a predetermined value, and if the specific section exists, it determines that there is a section where automatic driving is incapable and extracts the specific section as a section where automatic driving is incapable, whereas if the specific section does not exist, it determines that there is no section where automatic driving is incapable. The predetermined value and the required performance evaluation value are not particularly limited, and may be expressed by a numerical value or may be expressed by a level such as high, medium, or low.

[0036] The autonomous driving incapable section determination unit 39 may determine, as an autonomous driving incapable section, a section outside the operation design area on the map database 24. The autonomous driving incapable section determination unit 39 may obtain information on the autonomous driving incapable section from outside via the communication unit 25. The autonomous driving incapable section determination unit 39 may obtain, from outside via the communication unit 25, the necessary performance evaluation value of each section evaluated by the route required performance evaluation unit.

[0037] When the autonomous driving incapable section determination unit 39 determines that there is an autonomous driving incapable section, the vehicle allocation and merging unit 40 requests the dispatch of a reinforcing vehicle to the merging area and drives the autonomous driving vehicle 10 to the merging area. The reinforcing vehicle is a second vehicle different from the autonomous driving vehicle 10. The reinforcing vehicle is a vehicle that can travel through the autonomous driving incapable section. The reinforcing vehicle is a leading vehicle that leads the following travel of the autonomous driving vehicle 10. The reinforcing vehicle is, for example, a vehicle that can travel by being driven by a driver. The merging area is an area between the current position of the autonomous driving vehicle 10 and the autonomous driving incapable section. The merging area is an area where the autonomous driving vehicle 10 and the reinforcing vehicle can safely stop and merge. For example, the merging area may be an area around a bus stop.

[0038] As an example, the vehicle allocation and merging unit 40 transmits a request for dispatching a reinforcing vehicle to the merging area to an external server via the communication unit 25 to arrange for the vehicle to be dispatched. As a result, the external server transmits a notification to the reinforcing vehicle to notify the driver of the reinforcing vehicle, and the reinforcing vehicle moves to the merging area by being driven by the driver. At the same time, the vehicle allocation and merging unit 40 executes automatic driving to drive the automatically-driven vehicle 10 to the merging area by the automatic driving control unit 38. As a result, the automatically-driven vehicle 10 and the reinforcing vehicle merge in the merging area. The merging here refers to a state in which the two vehicles are close enough to each other that the following driving unit 41 described later is able to follow each other.

[0039] The merging area is not particularly limited as long as it is an area between the current position of the autonomous vehicle 10 and the section where autonomous driving is not possible, and can be set appropriately based on a known method. The reinforcement vehicle may be an autonomous vehicle equipped with a sensor and a computing unit with higher performance than the autonomous vehicle 10 and capable of traveling through the section where autonomous driving is not possible. The reinforcement vehicle may be a vehicle compatible with remote assistance. The reinforcement vehicle may be a dedicated vehicle that travels only in a predetermined section including the section where autonomous driving is not possible.

[0040] When the automatic driving impossible section determination unit 39 determines that there is an automatic driving impossible section, the following driving unit 41 controls the driving of the automatic driving vehicle 10 so that the automatic driving vehicle 10 follows the reinforcement vehicle in the automatic driving impossible section (in other words, so that the automatic driving vehicle 10 drives in a convoy with the reinforcement vehicle as the leading vehicle). The following driving unit 41 makes the automatic driving vehicle 10 follow the reinforcement vehicle in the automatic driving impossible section, thereby making the automatic driving vehicle 10 travel through the automatic driving impossible section. The method of following driving by the following driving unit 41 is not particularly limited, and various known methods can be used. For example, the following driving unit 41 may control the driving of the automatic driving vehicle 10 so that the automatic driving vehicle 10 follows the reinforcement vehicle based on the result of the automatic driving vehicle 10 recognizing the reinforcement vehicle. For example, the following driving unit 41 may receive a control value for following driving from the reinforcement vehicle, and control the driving of the automatic driving vehicle 10 so that the automatic driving vehicle 10 follows the reinforcement vehicle based on the control value.

[0041] Next, an example of the autonomous driving of the autonomous vehicle 10 implemented by the driving assistance system 1 will be described with reference to the flowchart of FIG.

[0042] In the driving assistance system 1, when an operation input for starting the autonomous driving of the autonomous vehicle 10 and an input of the destination are made via, for example, an operation terminal such as a smartphone or an HMI (Human Machine Interface) of the autonomous vehicle 10, the autonomous driving ECU 30 executes the following processing. That is, first, the autonomous driving of the autonomous vehicle 10 toward the destination is started (step S1). Based on the acquired position information of the autonomous vehicle 10, it is determined whether the autonomous vehicle 10 has arrived at the destination (step S2). If the result of step S2 is NO, the autonomous driving incapable section determination unit 39 determines whether there is an autonomous driving incapable section on the route (step S3). If the result of step S3 is NO, the autonomous driving of the autonomous vehicle 10 to the destination is continued (step S4). Thereafter, the process returns to the determination of step S2.

[0043] If the answer is YES in step S3, the vehicle allocation and merging unit 40 requests the dispatch of the reinforcement vehicle to the merging area (step S5). The vehicle allocation and merging unit 40 causes the autonomously driven vehicle 10 to drive autonomously to the merging area (step S6). If the autonomously driven vehicle 10 arrives at the merging area (YES in step S7), the autonomously driven vehicle 10 is stopped in the merging area. If the reinforcement vehicle merges with the autonomously driven vehicle 10 in the merging area (YES in step S8), the following driving unit 41 executes following driving of the reinforcement vehicle (step S9). Based on the acquired position information of the autonomously driven vehicle 10, it is determined whether the autonomously driven vehicle 10 has passed through a section where autonomous driving is not possible (step S10).

[0044] If the answer is NO in step S10, the process returns to step S9, and the following driving unit 41 continues to drive the reinforcement vehicle. If the answer is YES in step S10, the following driving of the reinforcement vehicle is terminated, and the process proceeds to step S4, and the autonomous driving of the autonomous vehicle 10 to the destination is continued (resumed). On the other hand, if the answer is YES in step S1, or if an operation input to terminate the autonomous driving of the autonomous vehicle 10 is made via the operation terminal or HMI, the autonomous driving of the autonomous vehicle 10 is terminated.

[0045] As described above, in the driving assistance system 1, when the autonomous vehicle 10 drives autonomously along a route that includes a section where autonomous driving is not possible, the autonomous vehicle 10 drives by following the reinforcement vehicle in the section where autonomous driving is not possible. This allows the autonomous vehicle 10 to drive autonomously along a route that includes a section where autonomous driving is not possible. The roles of the autonomous vehicle 10 and the reinforcement vehicle can be shared. It becomes possible to realize autonomous driving that is compatible with driving on many routes. It becomes possible to provide seamless driving assistance on routes that cross sections where autonomous driving is not possible.

[0046] In autonomous driving transportation services, an operational design area is set, but the risk of sections occurring outside the operational design area on the route during service provision due to dynamic factors such as sudden changes in weather or congestion, construction sections, or accidents involving other transportation participants cannot be completely eliminated. In response to this, in the driving assistance system 1, the autonomous vehicle 10 extracts sections on the route that are outside the operational design area and are not autonomously driven, arranges for a reinforcement vehicle that can traverse the sections that are not autonomously driven to join the vehicle, and traverses the sections that are not autonomously driven by temporarily following the reinforcement vehicle. This makes it possible to improve the continuity of the service of the autonomous vehicle 10.

[0047] In the driving assistance system 1, the automatic driving incapable section determination unit 39 determines a specific section on the route where the performance required for automatic driving exceeds a predetermined value as an automatic driving incapable section. In this case, the automatic driving incapable section can be determined by using the performance required for automatic driving of the route.

[0048] In the driving assistance system 1, the predetermined value is set based on the performance related to autonomous driving of the autonomous driving vehicle 10. In this case, the performance related to autonomous driving of the autonomous driving vehicle 10 can be used to set the predetermined value.

[0049] When autonomous driving incapable section determination unit 39 determines that there is an autonomous driving incapable section, driving assistance system 1 requests the dispatch of a reinforcing vehicle to the merging area by vehicle dispatch and merging unit 40 and drives the autonomous vehicle to the merging area. This allows autonomous vehicle 10 to efficiently merge with the reinforcing vehicle when following driving is performed by following driving unit 41.

[0050] In the driving assistance system 1, the reinforcing vehicle may be a vehicle that travels only in a predetermined section including the section where automatic driving is not possible. For example, the reinforcing vehicle may be a dedicated vehicle that waits in a waiting area around the predetermined section including the section where automatic driving is not possible. The reinforcing vehicle may be a dedicated vehicle that travels back and forth in the predetermined section including the section where automatic driving is not possible. In the case of an autonomous driving vehicle, the reinforcing vehicle may be a vehicle that is configured to be capable of autonomous driving only in the predetermined section including the section where automatic driving is not possible. In this case, the reinforcing vehicle can be specialized for traveling in the predetermined section including the section where automatic driving is not possible.

[0051] In the driving assistance system 1, as described above, the autonomous vehicle 10 may be a remote assistance compatible vehicle. In this case, for example, if a sudden downpour narrows the measurement range of the external sensor 22 of the autonomous vehicle 10, and a case occurs in which it is not possible to judge whether to start turning right at the intersection (that is, the right turn section at the intersection is included as an area where autonomous driving is not possible), it is difficult to ensure safety even by remote operation with the external sensor 22 of the autonomous vehicle 10. In this regard, if the reinforcing vehicle is an autonomous vehicle, if the reinforcing vehicle is equipped with an external sensor 22 with good performance that is resistant to rain, the measurement range of the reinforcing vehicle can be sufficiently ensured even in rainy weather. Therefore, the autonomous vehicle 10 can safely travel through the right turn section at the intersection by following the reinforcing vehicle.

[0052] 3(a), 3(b), 3(c), 4(a), 4(b), and 4(c) are schematic overhead views for explaining an example of autonomous driving of an autonomous vehicle 10 implemented by a driving assistance system 1. In the figure, a driving lane L1 constitutes a route for autonomous driving, and an autonomous driving incapable section H, which is a construction section, exists on the driving lane L1. In the example shown in FIG. 3(a), the autonomous vehicle 10 is autonomously driving along the driving lane L1 toward a destination. At this time, the autonomous driving incapable section determination unit 39 determines that an autonomous driving incapable section H exists on the driving lane L1. As shown in FIG. 3(a) and FIG. 3(b), a reinforcing vehicle 110 is arranged by the vehicle dispatch and merging unit 40, and the autonomous vehicle 10 stops at the merging area A and waits. The dispatched reinforcement vehicle 110, for example, driven by a driver, heads from a waiting area around the section H where autonomous driving is not possible to the merging area A and merges with the autonomously driven vehicle 10.

[0053] As shown in Figures 3(c) and 4(a), the reinforcing vehicle 110 departs and travels through the section H where autonomous driving is not possible, while the following travel unit 41 causes the autonomously driven vehicle 10 to follow the reinforcing vehicle 110. As shown in Figures 4(b) and 4(c), when the autonomously driven vehicle 10 passes through the section H where autonomous driving is not possible, the following travel ends. Thereafter, the autonomously driven vehicle 10 continues (resumes) autonomous driving to the destination, while the reinforcing vehicle 110 returns to, for example, a waiting area around the section H where autonomous driving is not possible, and waits to be arranged by the next autonomously driven vehicle to lead the section H where autonomous driving is not possible.

[0054] In the example of Fig. 3(a) to Fig. 4(c), driving assistance can be maintained by the reinforcement vehicle 110 that continues to piston-transport the autonomously-driving vehicle 10 only in the autonomously-driving-prohibited section H, and by normal autonomous driving in sections other than the autonomously-driving-prohibited section H. The autonomously-driving-prohibited section H, where autonomous driving is difficult, is not randomly dotted on the map, but is highly location-dependent. Therefore, by configuring the reinforcement vehicle 110 to be located in the section H where autonomous driving is not possible, the driving assistance system 1 can be operated efficiently and effectively.

[0055] Fig. 5 is a block diagram showing a configuration of a driving assistance system according to a modified example. As shown in Fig. 5, the autonomous driving ECU 30 may further include an information providing unit 42 in addition to the functional configuration in Fig. 1. The information providing unit 42 transmits sensor information of the autonomous driving vehicle 10 (e.g., detection results of the external sensor 22) to the reinforcement vehicle 110 via the communication unit 25. This allows the reinforcement vehicle 110 to compensate for blind spots created by the autonomous driving vehicle 10.

[0056] Fig. 6 is a block diagram showing the configuration of a driving assistance system according to another modified example. As shown in Fig. 6, the autonomous driving ECU 30 may further include a conductor function unit 43 in the functional configuration of Fig. 5. The conductor function unit 43 judges whether the autonomous driving vehicle 10 can start based on the situation of the autonomous driving vehicle 10. The conductor function unit 43 transmits the judgment result to the reinforcing vehicle 110. This makes it possible to prevent the reinforcing vehicle 110 from erroneously starting at a timing when the autonomous driving vehicle 10 cannot start.

[0057] Although various exemplary embodiments have been described above, various omissions, substitutions, and modifications may be made without being limited to the above-described exemplary embodiments. [Explanation of symbols]

[0058] 1...driving assistance system, 10...autonomous driving vehicle (first vehicle), 39...autonomous driving incapable section determination unit (determination unit), 40...vehicle dispatch and merging unit, 41...following driving unit, 110...reinforcement vehicle (second vehicle), A...merging area, H...autonomous driving incapable section, L1...driving lane (route).

Claims

1. A driving assistance system for driving a first vehicle in an autonomous driving manner, A determination unit that determines whether or not there is an automatic driving unavailable section on a route of the automatic driving of the first vehicle, in which the first vehicle cannot travel by automatic driving; a following driving unit that controls driving of the first vehicle so that the first vehicle follows a second vehicle that is capable of traveling through the automatic driving impossible section when the determination unit determines that the automatic driving impossible section exists; and a vehicle allocation and merging unit that, when the determination unit determines that there is an area where automatic driving is not possible, requests the second vehicle to be dispatched to a merging area between a current position of the first vehicle and the area where automatic driving is not possible, and drives the first vehicle to the merging area; The second vehicle is an autonomous vehicle configured to be autonomously driven only in a predetermined section including the autonomously driven section, the second vehicle is a dedicated vehicle waiting in a waiting area around the predetermined section, A driving assistance system, wherein the second vehicle is a dedicated vehicle that travels back and forth between the specified section.

2. A driving assistance system as described in claim 1, comprising a conductor function unit that determines whether the first vehicle, which is stopped and waiting in the merging area, can depart based on the status of the first vehicle, and transmits the result of that determination to the second vehicle.

3. A driving assistance system as described in claim 1 or 2, wherein, after the first vehicle has passed through the section where automatic driving is not possible, the following driving by the following driving unit is terminated, automatic driving of the first vehicle is resumed, and the second vehicle is returned to the waiting area and kept waiting.

4. The driving assistance system according to any one of claims 1 to 3, wherein the determination unit determines a specific section on the route where a performance required for autonomous driving exceeds a predetermined value as the autonomous driving incapable section.

5. The driving assistance system according to claim 4 , wherein the predetermined value is set based on an autonomous driving performance of the first vehicle.

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