Driving assistance device and computer program

Abstract

To provide a driving assistance device and a computer program with which it is possible to prevent an unrecommended lane change from being made when passing through a toll gate and appropriately conduct driving assistance.SOLUTION: A scheduled travel route that a vehicle travels is acquired; gate information is acquired, the information pertaining to the gate arrangement of a toll gate that exists in the scheduled travel route a prescribed distance or more ahead of the own vehicle position and is to be passed through; map information that includes lane shape and the gate information are used to acquire a candidate for a lane movement manner that is selectable when the vehicle passes through the toll gate along the scheduled travel route; and cost for the acquired candidate for the lane movement manner is calculated, taking into account a lane change position where a lane change is made and the calculated costs are compared, and then the lane movement manner for the vehicle that is recommended when the vehicle passes through the toll gate is selected from the candidates for the lane movement manner.SELECTED DRAWING: Figure 16

Description

[Technical Field]

[0001] The present invention relates to a driving assistance device and a computer program for assisting driving of a vehicle. [Background technology]

[0002] In order to provide appropriate driving assistance when a vehicle needs to change lanes from the lane in which it is currently traveling to another lane in the future, it is important to specify in advance when and how the vehicle should change lanes, i.e., a recommended lane change pattern. However, when passing through a toll gate installed at an interchange on a highway or the like, various lane change patterns are possible depending on the lane in which the vehicle is traveling and the gates through which it passes, and it is difficult to specify a recommended lane change pattern from among them.

[0003] Therefore, WO 2018 / 142576 proposes a technology for generating an action plan for a vehicle engaged in autonomous driving, in which when the vehicle is within a specified distance of a toll gate, a camera installed on the vehicle captures an image of the area in front of the vehicle to detect the status of the toll gate, and calculates a score indicating the suitability of the vehicle to pass through each gate, taking into account the direction of the destination, the congestion status of the gate, the type of gate, etc., and then comparing the calculated scores to select a gate that is recommended for passing through. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] WO 2018 / 142576 (paragraphs 0054-0090, Figure 10) Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology of Patent Document 1 does not take into consideration the lane change position required to pass through the gate when selecting a gate recommended for passage from among multiple gates at the toll gate. For example, as shown in Figure 18, when comparing section L1 from the point where the lane markings disappear before the toll gate to the gate entrance with section L2 from the gate exit to the point where the lane markings resume after passing through the toll gate, if L2 is shorter than L1, making lane changes at L1 rather than L2 reduces the likelihood of making an unreasonable lane change. Therefore, it is more desirable to pass through gates A and B, which require lane changes at L1, than gates C and D, which require lane changes at L2.

[0006] However, in the above-mentioned Patent Document 1, the gate to be passed through is selected without taking into consideration the lane change position as described above, so there was a problem that, for example, of the four gates A to D shown in Figure 18, if gates A and B are congested, gates C and D are preferentially selected as the gates to be passed through.

[0007] The present invention has been made to solve the above-mentioned problems in the prior art, and aims to provide a driving assistance device and computer program that selects a recommended lane movement pattern for a vehicle when passing through a toll gate, taking into account the lane change position at which the lane change will occur, thereby preventing unrecommended lane changes from being made while the vehicle is traveling and enabling driving assistance to be carried out appropriately. [Means for solving the problem]

[0008] In order to achieve the above object, a first driving assistance device according to the present invention comprises: a planned driving route acquisition means for acquiring a planned driving route along which a vehicle will travel; a gate information acquisition means for acquiring gate information which is information about the location of gates of toll gates that the vehicle will pass through and which are located ahead of the vehicle's position by a predetermined distance or more on the planned driving route; a candidate acquisition means for acquiring candidate lane movement modes which can be selected when the vehicle passes through the toll gate along the planned driving route, using map information including lane shapes and the gate information; a cost calculation means for calculating a cost for the candidate lane movement modes acquired by the candidate acquisition means, taking into account a lane change position where a lane change will be performed; and a recommended movement mode selection means for comparing the cost calculated by the cost calculation means and selecting a lane movement mode of the vehicle that is recommended when passing through the toll gate from among the candidate lane movement modes. The candidate acquisition means uses map information including lane shapes and the gate information to acquire a lane network, which is a network showing lane movements that can be selected when the vehicle passes through the toll gate along the planned driving route, sets a start position where the vehicle will begin moving and a target position to which the vehicle will move in the lane network, and acquires a route connecting the start position and the target position in the lane network as a candidate for the lane movement pattern.The lane network divides the planned driving route into boundaries, each consisting of a branch point position, a position where lanes increase or decrease, a point where the dividing line disappears just before the toll gate, a point where the dividing line resumes after passing through the toll gate, a gate entrance, and a gate exit, and sets a node for each lane located on the boundary of each divided section, and is a network having links connecting the set nodes. The second driving assistance device according to the present invention includes a planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel, a gate information acquisition means for acquiring gate information which is information on the location of gates of toll gates to be passed along the planned driving route and which are located ahead of the vehicle's position by a predetermined distance or more, a candidate acquisition means for acquiring candidates for lane movement modes which can be selected when the vehicle passes through the toll gate along the planned driving route, using map information including lane shapes and the gate information, and a cost calculation means for calculating a cost for the candidates for lane movement modes acquired by the candidate acquisition means, taking into account lane change positions at which the lane change will be performed. and a recommended movement mode selection means for comparing the costs calculated by the cost calculation means and selecting from among the candidate lane movement modes a lane movement mode that is recommended for the vehicle when passing through the toll gate, wherein the cost calculation means sets a recommended position at a point a predetermined distance before the toll gate or branch point for a candidate lane movement mode that involves a lane change to pass through the toll gate or branch point, among the candidate lane movement modes acquired by the candidate acquisition means, and calculates a higher cost for the candidate lane movement mode whose lane change position is located farther away from the recommended position. Furthermore, a third driving assistance device according to the present invention comprises planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel, gate information acquisition means for acquiring gate information which is information about the location of gates of toll gates that the vehicle will pass through and which are located ahead of the vehicle's position by a predetermined distance or more on the planned driving route, candidate acquisition means for acquiring candidate lane movement modes which can be selected when the vehicle passes through the toll gate along the planned driving route using map information including lane shapes and the gate information, cost calculation means for calculating a cost for the candidate lane movement modes acquired by the candidate acquisition means, taking into account a lane change position where a lane change will be made, and recommended movement mode selection means for comparing the costs calculated by the cost calculation means and selecting a lane movement mode of the vehicle that is recommended when passing through the toll gate, wherein the cost calculation means a first calculation condition that, among the candidates for lane movement mode acquired by the candidate acquisition means, for a candidate for lane movement mode involving a lane change between the point where the dividing line disappears before the toll gate and the entrance of the gate, the closer the distance from the lane change position where the lane change occurs to the entrance of the gate, and a second calculation condition that, among the candidates for lane movement mode acquired by the candidate acquisition means, for a candidate for lane movement mode involving a lane change between the exit of the gate and the point where the dividing line resumes after passing through the toll gate, the closer the distance from the lane change position where the lane change occurs to the exit of the gate, the higher the cost is added; and a second calculation condition that adds a higher cost, and if the distance from the exit of the gate to the point where the lane markings resume after passing through the toll gate is longer than the distance from the point where the lane markings disappear before the toll gate to the entrance of the gate, the added cost amount under the first calculation condition is greater than the added cost amount under the second calculation condition, and if the distance from the point where the lane markings disappear before the toll gate to the entrance of the gate is longer than the distance from the exit of the gate to the point where the lane markings resume after passing through the toll gate, the added cost amount under the second calculation condition is greater than the added cost amount under the first calculation condition. . Note that "lane change" is not limited to moving between lanes in sections where lanes are divided by dividing lines, but also includes moving left or right in sections where there are no dividing lines (for example, before or after a gate in a toll booth).

[0009] Furthermore, a computer program according to the present invention is a program for generating assistance information used for driving assistance implemented in a vehicle. Specifically, the computer program causes a computer to function as: a planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel; a gate information acquisition means for acquiring gate information which is information about the location of toll gates at toll gates that are to be passed through and are located a predetermined distance or more ahead of the vehicle's position on the planned driving route; a candidate acquisition means for acquiring candidate lane movement modes that can be selected when the vehicle passes through the toll gate along the planned driving route using map information including lane shapes and the gate information; a cost calculation means for calculating a cost for the candidate lane movement modes acquired by the candidate acquisition means, taking into account the lane change position at which the lane change will be performed; and a recommended movement mode selection means for comparing the costs calculated by the cost calculation means and selecting a lane movement mode recommended for the vehicle when passing through the toll gate from among the candidate lane movement modes. The candidate acquisition means uses map information including lane shapes and the gate information to acquire a lane network, which is a network showing lane movements that can be selected when the vehicle passes through the toll gate along the planned driving route, sets a start position from which the vehicle starts to move and a target position to which the vehicle will move in the lane network, and acquires routes connecting the start position and the target position in the lane network as candidates for the lane movement mode, and the lane network divides the planned driving route into sections with boundaries including positions of branch points, positions where lanes increase or decrease, points where lane markings disappear before the toll gate, points where lane markings resume after passing through the toll gate, gate entrances, and gate exits, and sets nodes for each lane located on the boundary of each divided section, and is a network having links connecting the set nodes. . [Effects of the Invention]

[0010] According to the driving assistance device and computer program of the present invention having the above configuration, the lane change mode of the vehicle recommended for passing through the toll gate is selected in consideration of the lane change position before approaching the toll gate, making it possible to appropriately select in advance the lane change mode for the recommended lane change when passing through the toll gate. As a result, it is possible to prevent unrecommended lane changes from being made while the vehicle is traveling, and to appropriately implement driving assistance. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic configuration diagram illustrating a driving assistance system according to an embodiment of the present invention. [Figure 2]1 is a block diagram showing the configuration of a driving assistance system according to an embodiment of the present invention. [Figure 3] 1 is a block diagram showing a navigation device according to an embodiment of the present invention; [Figure 4] 4 is a flowchart of an autonomous driving assistance program according to the present embodiment. [Figure 5] FIG. 2 is a diagram showing an area for which high-precision map information is acquired. [Figure 6] FIG. 10 is a diagram showing an example of an avoidance trajectory, which is one of dynamic traveling trajectories. [Figure 7] 10 is a flowchart of a sub-processing program of a static traveling trajectory generation process. [Figure 8] FIG. 2 is a diagram showing an example of a planned driving route of a vehicle. [Figure 9] FIG. 9 is a diagram showing an example of a lane network constructed for the planned travel route shown in FIG. 8. [Figure 10] 10 is a diagram showing an example of a lane flag indicating the correspondence between lanes included in a road before passing through a branch point and lanes included in a road after passing through the branch point; FIG. [Figure 11] FIG. 1 is a diagram showing candidate routes. [Figure 12] FIG. 1 is a diagram showing candidate routes. [Figure 13] FIG. 10 is a diagram showing lane change positions set for a candidate route. [Figure 14] FIG. 10 is a diagram showing candidate routes in which lane change positions are identified. [Figure 15] FIG. 10 is a diagram showing an example of a method for calculating a lane change position cost. [Figure 16] FIG. 10 is a diagram showing an example of a method for calculating a lane change position cost. [Figure 17] FIG. 10 is a diagram comparing the total costs finally calculated for each candidate route. [Figure 18] FIG. 1 is a diagram illustrating a problem with the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0012] An embodiment in which a driving assistance device according to the present invention is embodied in a navigation device 1 will be described in detail below with reference to the drawings. First, a schematic configuration of a driving assistance system 2 including a navigation device 1 according to this embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic configuration diagram showing the driving assistance system 2 according to this embodiment. Fig. 2 is a block diagram showing the configuration of the driving assistance system 2 according to this embodiment.

[0013] As shown in Fig. 1, a driving assistance system 2 according to this embodiment basically includes a server device 4 provided in an information distribution center 3, and a navigation device 1 that is mounted on a vehicle 5 and provides various types of assistance related to the autonomous driving of the vehicle 5. The server device 4 and the navigation device 1 are configured to be able to send and receive electronic data to and from each other via a communication network 6. Note that instead of the navigation device 1, other on-board devices mounted on the vehicle 5 or a vehicle control device that controls the vehicle 5 may be used.

[0014] Here, vehicle 5 is a vehicle capable of manual driving, in which the vehicle drives based on the user's driving operations, as well as assisted driving using automatic driving assistance, in which the vehicle automatically drives along a pre-set route or road without the user's driving operations.

[0015] Furthermore, autonomous driving assistance may be provided for all road sections, or may be configured to be provided only while the vehicle is traveling on a specific road section (for example, a highway with a gate (manned or unmanned, toll or free) at the boundary). In the following explanation, the autonomous driving section in which autonomous driving assistance is provided includes all road sections, including general roads and highways, as well as parking lots, and the explanation will be given assuming that autonomous driving assistance is basically provided from the time the vehicle starts traveling until it ends traveling (until the vehicle is parked). However, autonomous driving assistance is not always provided when the vehicle is traveling on an autonomous driving section, but is preferably provided only when the user selects to provide autonomous driving assistance (for example, by turning on the autonomous driving start button) and it is determined that autonomous driving assistance is possible. On the other hand, vehicle 5 may be a vehicle capable of only assisted traveling using autonomous driving assistance.

[0016] In vehicle control in automated driving assistance, for example, the current position of the vehicle, the lane the vehicle is traveling on, and the positions of surrounding obstacles are detected at any time, and vehicle control of the steering, drive source, brakes, etc. is automatically performed so that the vehicle travels at a speed according to a speed plan generated along a travel trajectory generated by the navigation device 1, as will be described later. Note that in assisted driving with automated driving assistance in this embodiment, lane changes, right and left turns, and parking operations are also performed by performing vehicle control with the automated driving assistance described above, but special driving operations such as lane changes, right and left turns, and parking operations may be performed by manual driving without using automated driving assistance.

[0017] On the other hand, the navigation device 1 is an on-board device that is mounted on the vehicle 5 and displays a map of the area around the vehicle's position based on map data stored in the navigation device 1 or map data acquired from an external source, allows the user to input a destination, displays the vehicle's current position on a map image, and provides travel guidance along a set guide route. In this embodiment, various types of assistance information related to autonomous driving assistance are generated, particularly when the vehicle is performing assisted driving using autonomous driving assistance. Examples of assistance information include a recommended driving trajectory for the vehicle (including recommended lane movement patterns), selection of a parking position for parking the vehicle at the destination, and a speed plan indicating the vehicle speed when driving. Details of the navigation device 1 will be described later.

[0018] The server device 4 also performs a route search in response to a request from the navigation device 1. Specifically, when a destination is set in the navigation device 1 or when a route re-search (rerouting) is performed, information necessary for the route search, such as the starting point and destination, is transmitted from the navigation device 1 to the server device 4 along with the route search request (however, in the case of a re-search, information about the destination does not necessarily need to be transmitted). Upon receiving the route search request, the server device 4 performs a route search using map information stored in the server device 4 and identifies a recommended route from the starting point to the destination. The identified recommended route is then transmitted to the navigation device 1 that issued the request. The navigation device 1 then provides the user with information about the received recommended route, sets the recommended route as a guide route, and generates various types of assistance information related to autonomous driving assistance according to the guide route. As a result, even if the map information stored in the navigation device 1 at the time of route search is an old version or the navigation device 1 does not have any map information at all, it is possible to provide an appropriate recommended route to the destination based on the latest version of the map information stored in the server device 4.

[0019] Furthermore, the server device 4 stores high-precision map information, which is map information with higher accuracy, in addition to the normal map information used for the route search. The high-precision map information includes, for example, information on the lane shape of the road (such as the road shape and curvature for each lane, and lane width) and road markings (such as center lines, lane boundaries, outer lane lines, guide lines, and guidance strips). It also includes information on intersections, parking lots, and toll booths. The server device 4 distributes the high-precision map information in response to a request from the navigation device 1, and the navigation device 1 uses the high-precision map information distributed from the server device 4 to generate various types of support information for autonomous driving assistance, as described below. Note that the high-precision map information is basically map information that covers only roads (links) and their surrounding areas, but it may also be map information that includes areas other than the surrounding areas of the roads.

[0020] However, the above-described route search process does not necessarily have to be performed by the server device 4, and may be performed by the navigation device 1 as long as the navigation device 1 has map information. Furthermore, the high-precision map information may not be distributed from the server device 4, but may be stored in the navigation device 1 in advance.

[0021] The communication network 6 includes numerous base stations located throughout the country and communication companies that manage and control each base station, and is configured by connecting the base stations and communication companies to each other via wire (optical fiber, ISDN, etc.) or wirelessly. Here, the base stations have transceivers (transmitters / receivers) and antennas that communicate with the navigation device 1. The base stations perform wireless communications between communication companies, and are also end points of the communication network 6, and have the role of relaying communications between the navigation device 1 within the range (cell) of the base station's radio waves and the server device 4.

[0022] Next, the configuration of the server device 4 in the driving assistance system 2 will be described in more detail with reference to Fig. 2. As shown in Fig. 2, the server device 4 includes a server control unit 11, a server-side map DB 12 as information recording means connected to the server control unit 11, a high-precision map DB 13, and a server-side communication device 14.

[0023] The server control unit 11 is a control unit (MCU, MPU, etc.) that controls the entire server device 4, and includes a CPU 21 as an arithmetic and control device, a RAM 22 used as a working memory when the CPU 21 performs various arithmetic processing, a ROM 23 in which control programs and the like are recorded, and a flash memory 24 for storing programs read from the ROM 23. The server control unit 11 has various means as processing algorithms together with the ECU of the navigation device 1, which will be described later.

[0024] On the other hand, the server-side map DB 12 is a storage means for storing server-side map information, which is the latest version of map information registered based on external input data and input operations. Here, the server-side map information is composed of various information necessary for route search, route guidance, and map display, including the road network. For example, it includes network data including nodes and links indicating the road network, link data related to roads (links), node data related to node points, intersection data related to each intersection, point data related to points such as facilities, map display data for displaying the map, search data for searching for routes, and search data for searching for points.

[0025] The high-precision map DB 13 is a storage means for storing high-precision map information 15, which is map information with higher accuracy than the server-side map information. The high-precision map information 15 is map information that stores more detailed information, particularly about roads and parking lots on which vehicles travel. In this embodiment, the high-precision map information 15 includes, for example, information about lane shapes (such as the road shape and curvature for each lane, and lane width) and road dividing lines (such as center lines, lane boundaries, outer lane lines, guide lines, and guide strips) drawn on roads. Furthermore, the high-precision map information 15 stores data representing road gradients, cants, banks, merging sections, areas where the number of lanes decreases, areas where road width narrows, and railroad crossings; data representing corners, such as the radius of curvature, intersections, T-junctions, and corner entrances and exits; data representing road attributes, such as downhill roads and uphill roads; and data representing road types, such as general roads (national highways, prefectural roads, and narrow streets) as well as toll roads (such as national expressways, urban expressways, motorways, general toll roads, and toll bridges). In addition to the number of lanes on a road, information identifying the traffic divisions in the direction of travel for each lane and the connections between roads (specifically, the correspondence between the lanes on the road before passing through a branch point and the lanes on the road after passing through the branch point) is also recorded. Furthermore, the speed limit set for the road is also stored. The high-precision map DB 13 also includes information about toll gates. More specifically, this information is information about the gates installed at the toll gates (hereinafter referred to as gate information), including the number of gates, the gate locations (including information identifying the entrance and exit positions of the gates, and information identifying the correspondence between the gates and the lanes before and after the toll gate), and the gate types (general-use, ETC-only, and general ETC-compatible). Toll gates are generally installed at interchanges on expressways, but the information also includes toll gates installed at the entrances and exits of toll roads other than expressways and toll gates installed at the entrances and exits of facilities. While high-precision map information basically covers only roads (links) and their surrounding areas, it may also be map information that includes areas other than the surrounding areas of the roads. In the example shown in FIG. 2, the server-side map information stored in the server-side map DB 12 and the high-accuracy map information 15 are different map information, but the high-accuracy map information 15 may be a part of the server-side map information.

[0026] On the other hand, the server-side communication device 14 is a communication device for communicating with the navigation device 1 of each vehicle 5 via the communication network 6. In addition to the navigation device 1, it is also possible to receive traffic information including congestion information, regulation information, traffic accident information, etc. transmitted from the Internet network or a traffic information center, such as a VICS (registered trademark: Vehicle Information and Communication System) center.

[0027] Next, the schematic configuration of the navigation device 1 mounted on the vehicle 5 will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the navigation device 1 according to this embodiment.

[0028] 3, the navigation device 1 according to this embodiment includes a current position detection unit 31 that detects the current position of the vehicle in which the navigation device 1 is installed, a data recording unit 32 that records various data, a navigation ECU 33 that performs various calculations based on input information, an operation unit 34 that accepts user operations, a liquid crystal display 35 that displays to the user a map of the area around the vehicle and information about the guide route (planned route of the vehicle) set in the navigation device 1, a speaker 36 that outputs audio guidance regarding the route guidance, a DVD drive 37 that reads a DVD as a storage medium, and a communication module 38 that communicates with an information center such as a probe center or a VICS center. The navigation device 1 is also connected to an external camera 39 and various sensors installed in the vehicle in which the navigation device 1 is installed via an in-vehicle network such as a CAN. The navigation device 1 is also connected to a vehicle control ECU 40 that performs various controls on the vehicle in which the navigation device 1 is installed, allowing bidirectional communication.

[0029] Each of the components of the navigation device 1 will be explained below in order. The current position detection unit 31 is composed of a GPS 41, a vehicle speed sensor 42, a steering sensor 43, a gyro sensor 44, etc., and is capable of detecting the current vehicle position, direction, vehicle traveling speed, current time, etc. Here, the vehicle speed sensor 42 in particular is a sensor for detecting the vehicle's travel distance and speed, and generates pulses in response to the rotation of the vehicle's drive wheels and outputs the pulse signals to the navigation ECU 33. The navigation ECU 33 then calculates the rotation speed of the drive wheels and travel distance by counting the generated pulses. Note that the navigation device 1 does not need to be equipped with all four types of sensors described above, and the navigation device 1 may be configured to be equipped with only one or more of these types of sensors.

[0030] The data recording unit 32 also includes a hard disk (not shown) as an external storage device and recording medium, and a recording head (not shown) which is a driver for reading the map information DB 45, cache 46, predetermined programs, etc. recorded on the hard disk and writing predetermined data to the hard disk. Note that the data recording unit 32 may include a flash memory, a memory card, or an optical disk such as a CD or DVD instead of a hard disk. In addition, in this embodiment, as described above, the server device 4 searches for a route to the destination, so the map information DB 45 may be omitted. Even if the map information DB 45 is omitted, it is possible to obtain map information from the server device 4 as needed.

[0031] Here, the map information DB45 is a storage means that stores, for example, link data related to roads (links), node data related to node points, search data used for processing related to route search and change, facility data related to facilities, map display data for displaying maps, intersection data related to each intersection, search data for searching for points, etc.

[0032] On the other hand, the cache 46 is a storage means for storing high precision map information 15 previously distributed from the server device 4. The storage period can be set as appropriate, for example, it may be a predetermined period (for example, one month) from the time of storage, or it may be until the ACC power supply (accessory power supply) of the vehicle is turned off. Furthermore, once the amount of data stored in the cache 46 reaches an upper limit, the oldest data may be deleted in order. Then, the navigation ECU 33 generates various types of assistance information related to autonomous driving assistance using the high precision map information 15 stored in the cache 46. Details will be described later.

[0033] Meanwhile, the navigation ECU (Electronic Control Unit) 33 is an electronic control unit that controls the entire navigation device 1. It includes a CPU 51 as a calculation device and control device, a RAM 52 that serves as a working memory for the CPU 51 to perform various calculation processes and stores route data and other information used when a route is searched, a ROM 53 that stores control programs as well as the automated driving assistance program (see FIG. 4 ) described below, and a flash memory 54 that stores programs read from the ROM 53. The navigation ECU 33 also includes various processing algorithms. For example, the planned driving route acquisition means acquires the planned driving route along which the vehicle will travel. The gate information acquisition means acquires gate information, which is information about the locations of toll gates at toll gates that the vehicle will pass through along the planned driving route and that are located a predetermined distance or more ahead of the vehicle's current position. The candidate acquisition means uses map information, including lane shapes, and the gate information to acquire candidate lane movement patterns that the vehicle can select when passing through toll gates along the planned driving route. The cost calculation means calculates a cost for the lane change mode candidates acquired by the candidate acquisition means, taking into consideration the lane change position where the lane change will be performed. The recommended movement mode selection means compares the costs calculated by the cost calculation means and selects a lane change mode of the vehicle recommended for passing through the toll gate from among the lane change mode candidates.

[0034] The operation unit 34 is operated when inputting a departure point as a starting point of a trip and a destination point as a destination of a trip, and has a plurality of operation switches (not shown) such as various keys and buttons. The navigation ECU 33 controls the execution of various corresponding operations based on switch signals output by pressing each switch. The operation unit 34 may have a touch panel provided on the front surface of the liquid crystal display 35. It may also have a microphone and a voice recognition device.

[0035] The LCD display 35 also displays map images including roads, traffic information, operation guidance, operation menus, key guidance, guidance information along the guided route (planned driving route), news, weather forecasts, time, emails, television programs, etc. Note that a HUD or HMD may be used instead of the LCD display 35.

[0036] The speaker 36 also outputs voice guidance for guiding the vehicle along a guide route (planned travel route) based on instructions from the navigation ECU 33, and traffic information guidance.

[0037] The DVD drive 37 is a drive that can read data recorded on a recording medium such as a DVD or CD. Based on the read data, music and video are played, and the map information DB 45 is updated. Instead of the DVD drive 37, a card slot for reading and writing data to a memory card may be provided.

[0038] The communication module 38 is a communication device for receiving traffic information, probe information, weather information, etc. transmitted from a traffic information center, such as a VICS center or a probe center, and is, for example, a mobile phone or DCM. It also includes a vehicle-to-vehicle communication device for communicating between vehicles and a road-to-vehicle communication device for communicating with roadside devices. It is also used to transmit and receive route information and high-precision map information 15 searched by the server device 4 to and from the server device 4.

[0039] The exterior camera 39 is composed of a camera using a solid-state image sensor such as a CCD, and is mounted above the vehicle's front bumper with its optical axis oriented downward at a predetermined angle from the horizontal. The exterior camera 39 captures an image of the area ahead of the vehicle when the vehicle is traveling in an autonomous driving zone. The navigation ECU 33 processes the captured image to detect obstacles such as lane markings on the road on which the vehicle is traveling and other nearby vehicles. For example, if a new obstacle is detected on the current traveling path, the navigation ECU 33 generates a new traveling path that avoids or follows the obstacle. The exterior camera 39 may be positioned at the rear or side of the vehicle, in addition to the front. Instead of a camera, sensors such as millimeter-wave radar or laser sensors, or vehicle-to-vehicle communication or road-to-vehicle communication may be used to detect obstacles.

[0040] The vehicle control ECU 40 is an electronic control unit that controls the vehicle equipped with the navigation device 1. The vehicle control ECU 40 is connected to each drive unit of the vehicle, such as the steering, brakes, and accelerator, and in this embodiment, after automatic driving assistance has started in the vehicle, the vehicle control ECU 40 controls each drive unit to implement automatic driving assistance for the vehicle. If an override is performed by the user during automatic driving assistance, the ECU 40 detects that an override has been performed.

[0041] Here, after starting to travel, the navigation ECU 33 transmits various types of assistance information related to the autonomous driving assistance generated by the navigation device 1 to the vehicle control ECU 40 via the CAN. Then, the vehicle control ECU 40 uses the received various types of assistance information to implement the autonomous driving assistance after starting to travel. Examples of the assistance information include a recommended traveling trajectory for the vehicle, a speed plan indicating the vehicle speed when traveling, etc.

[0042] Next, an automatic driving assistance program executed by the CPU 51 in the navigation device 1 according to this embodiment having the above configuration will be described with reference to Fig. 4. Fig. 4 is a flowchart of the automatic driving assistance program according to this embodiment. Here, the automatic driving assistance program is executed when the vehicle starts traveling with automatic driving assistance after the ACC power supply (accessory power supply) of the vehicle is turned on, and is a program that performs assisted traveling with automatic driving assistance in accordance with assistance information generated by the navigation device 1. The programs shown in the flowcharts in Figs. 4 and 7 below are stored in the RAM 52 and ROM 53 provided in the navigation device 1, and are executed by the CPU 51.

[0043] First, in step (hereinafter abbreviated as S) 1 of the automatic driving assistance program, the CPU 51 acquires a route that the vehicle is scheduled to travel in the future (hereinafter referred to as planned travel route). The planned travel route of the vehicle is, for example, a recommended route to a destination searched for by the server device 4 when the destination is set by the user. If a destination is not set, a route that follows a road from the current position of the vehicle may be used as the planned travel route.

[0044] Furthermore, when searching for a recommended route, the CPU 51 first transmits a route search request to the server device 4. The route search request includes a terminal ID that identifies the navigation device 1 that sent the route search request, and information that identifies the departure point (e.g., the current position of the vehicle) and the destination. When re-searching, information that identifies the destination is not necessarily required. Thereafter, the CPU 51 receives searched route information transmitted from the server device 4 in response to the route search request. The searched route information is information (e.g., a series of links included in the recommended route) that identifies a recommended route (center route) from the departure point to the destination that the server device 4 has searched for using the latest version of map information based on the transmitted route search request. The search is performed using, for example, the well-known Dijkstra algorithm.

[0045] In addition, in the search for the recommended route, it is desirable to select a parking position (parking space) recommended for parking the vehicle in a parking lot at the destination, and search for a recommended route to the selected parking position. In other words, it is desirable that the searched recommended route include not only a route to the parking lot, but also a route showing the movement of the vehicle within the parking lot. Furthermore, when selecting a parking position, it is desirable to select a parking position that reduces the burden on the user by taking into consideration not only the movement of the vehicle to the parking position, but also the walking movement after parking the vehicle.

[0046] Next, in S2, the CPU 51 acquires high-precision map information 15 for a section within a predetermined distance from the current position of the vehicle along the planned driving route acquired in S1. For example, the high-precision map information 15 is acquired for the planned driving route included in the secondary mesh in which the vehicle is currently located. However, the area for which the high-precision map information 15 is acquired can be changed as appropriate. For example, the high-precision map information 15 may be acquired for an area within 3 km from the current position of the vehicle along the planned driving route. Alternatively, the high-precision map information 15 may be acquired for the entire planned driving route.

[0047] Here, the high-precision map information 15 is divided into rectangular areas (e.g., 500 m x 1 km) as shown in Fig. 5 and stored in the high-precision map DB 13 of the server device 4. Therefore, for example, when a planned driving route 61 is acquired as shown in Fig. 5, high-precision map information 15 is acquired for areas 62 to 64 including the planned driving route 61 within a secondary mesh that includes the current position of the vehicle. The high-precision map information 15 includes, for example, information on the lane shape and width of the road and road markings (center line, lane boundary line, outer lane line, guide line, guidance strip, etc.). It also includes information on intersections, parking lots, and toll gates. More specifically, the information on toll gates is gate information related to the gates installed at the toll gates, including the number of gates, gate locations (including information specifying the entrance and exit positions of the gates and information specifying the correspondence between the lanes before and after the toll gate and the gates), and gate type (general-use, ETC-only, or general ETC-compatible).

[0048] Furthermore, the high precision map information 15 is basically acquired from the server device 4, but if there is high precision map information 15 of an area that is already stored in the cache 46, it is acquired from the cache 46. Furthermore, the high precision map information 15 acquired from the server device 4 is temporarily stored in the cache 46.

[0049] Thereafter, in S3, the CPU 51 executes a static driving trajectory generation process (FIG. 7) described later. Here, the static driving trajectory generation process is a process for generating a static driving trajectory, which is a driving trajectory recommended for the vehicle to travel on roads included in the planned driving route, based on the planned driving route of the vehicle and the high-precision map information 15 acquired in S2. In particular, the CPU 51 identifies the driving trajectory recommended for the vehicle for each lane included in the planned driving route as the static driving trajectory. Note that, as described below, the static driving trajectory is generated for a section from the current position of the vehicle to a predetermined distance ahead in the traveling direction (for example, within the secondary mesh where the vehicle is currently located, or the entire section to the destination). Note that, although the predetermined distance can be changed as appropriate, the static driving trajectory is generated for an area that includes at least an area outside the range (detection range) in which road conditions around the vehicle can be detected by the exterior camera 39 or other sensors.

[0050] Next, in S4, the CPU 51 generates a speed plan for the vehicle when traveling along the static traveling track generated in S3, based on the high-precision map information 15 acquired in S2. For example, the CPU 51 calculates a recommended traveling speed for the vehicle when traveling along the static traveling track, taking into consideration speed limit information and speed change points (e.g., intersections, curves, railroad crossings, crosswalks, etc.) on the planned traveling route.

[0051] The speed plan generated in S4 is stored in the flash memory 54 or the like as support information to be used for the automatic driving support. In addition, an acceleration plan indicating the acceleration / deceleration of the vehicle required to realize the speed plan generated in S4 may also be generated as support information to be used for the automatic driving support.

[0052] Next, in S5, the CPU 51 performs image processing on the image captured by the exterior camera 39 to determine whether there are any factors affecting the vehicle's traveling, particularly those around the vehicle, that may affect the vehicle's traveling. The "factors affecting the vehicle's traveling" determined in S5 are dynamic factors that change in real time, excluding static factors based on road structure. For example, these factors include other vehicles traveling or parked ahead of the vehicle, parked vehicles, pedestrians ahead of the vehicle, and construction zones ahead of the vehicle. On the other hand, intersections, curves, railroad crossings, merging sections, and lane-narrowing sections are excluded. Even if other vehicles, pedestrians, or construction zones exist, they are excluded from the "factors affecting the vehicle's traveling" if they are unlikely to overlap with the vehicle's future traveling trajectory (e.g., if they are located far from the vehicle's future traveling trajectory). Instead of cameras, sensors such as millimeter-wave radar or laser sensors, vehicle-to-vehicle communication, or road-to-vehicle communication may be used to detect factors that may affect the vehicle's traveling.

[0053] In addition, for example, the real-time positions of each vehicle traveling on roads across the country may be managed by an external server, and the CPU 51 may obtain the positions of other vehicles located around the vehicle from the external server and perform the determination process of S5.

[0054] If it is determined that there is a factor in the vicinity of the host vehicle that may affect the running of the host vehicle (S5: YES), the process proceeds to S6. On the other hand, if it is determined that there is no factor in the vicinity of the host vehicle that may affect the running of the host vehicle (S5: NO), the process proceeds to S9.

[0055] In S6, the CPU 51 generates a new trajectory as a dynamic driving trajectory for returning to the static driving trajectory from the current position of the vehicle by avoiding or following the "factors that affect the driving of the host vehicle" detected in S5. The dynamic driving trajectory is generated for a section including the "factors that affect the driving of the host vehicle." The length of the section varies depending on the type of the factor. For example, if the "factors that affect the driving of the host vehicle" is another vehicle (forward vehicle) traveling ahead of the vehicle, an avoidance trajectory is generated as a dynamic driving trajectory 70, which is a trajectory that changes lanes to the right to overtake the forward vehicle 69, then changes lanes to the left to return to the original lane, as shown in FIG. 6. A following trajectory that follows the forward vehicle 69 a predetermined distance behind (or travels alongside) the forward vehicle 69 without overtaking the forward vehicle 69 may also be generated as the dynamic driving trajectory.

[0056] 6, the calculation method of the dynamic driving trajectory 70 will be explained as an example. First, the CPU 51 calculates a first trajectory L1 required for the vehicle to start turning the steering wheel and move to the right lane, and then return the steering wheel position to a straight-ahead direction. The first trajectory L1 is calculated by calculating the lateral acceleration (lateral G) that occurs when changing lanes based on the vehicle's current speed, and then using a clothoid curve to calculate a trajectory that is as smooth as possible and requires as short a distance as possible to change lanes, under the condition that the lateral G does not interfere with the automatic driving assistance and does not exceed an upper limit (e.g., 0.2 G) that does not cause discomfort to the vehicle occupants. Another condition is that an appropriate inter-vehicle distance D or more must be maintained between the vehicle and the preceding vehicle 69. Next, a second trajectory L2 is calculated, which is the trajectory for traveling in the right lane at the upper limit of the speed limit to overtake the preceding vehicle 69 and maintain an appropriate inter-vehicle distance D or more between the preceding vehicle 69. The second trajectory L2 is basically a straight trajectory, and the length of the trajectory is calculated based on the speed of the preceding vehicle 69 and the speed limit of the road. Next, a third trajectory L3 is calculated, which is the trajectory required to start turning the steering wheel and return to the left lane, and to return the steering position to a straight-ahead direction. The third trajectory L3 is calculated by calculating the lateral acceleration (lateral G) that occurs when changing lanes based on the vehicle's current speed, and using a clothoid curve, calculates a trajectory that is as smooth as possible and minimizes the distance required for changing lanes, on the condition that the lateral G does not interfere with the automated driving assistance and does not exceed an upper limit (e.g., 0.2 G) that does not cause discomfort to the vehicle occupants. Another condition is that an appropriate inter-vehicle distance D or more must be maintained between the vehicle and the preceding vehicle 69. Furthermore, since the dynamic driving trajectory is generated based on the road conditions around the vehicle acquired by the exterior camera 39 and other sensors, the area for which the dynamic driving trajectory is generated is at least within the range (detection range) in which the road conditions around the vehicle can be detected by the exterior camera 39 and other sensors.

[0057] Next, in S7, the CPU 51 reflects the dynamic driving trajectory newly generated in S6 on the static driving trajectory generated in S3. Specifically, the CPU 51 calculates the costs of the static driving trajectory and the dynamic driving trajectory from the current vehicle position to the end of the section including the "factors affecting the vehicle's driving," and selects the driving trajectory with the smallest cost. As a result, part of the static driving trajectory is replaced with the dynamic driving trajectory as needed. Note that, depending on the situation, the dynamic driving trajectory may not be replaced, i.e., the static driving trajectory generated in S3 may not change even when the dynamic driving trajectory is reflected. Furthermore, if the dynamic driving trajectory and the static driving trajectory are the same trajectory, the static driving trajectory generated in S3 may not change even when the dynamic driving trajectory is replaced.

[0058] Next, in S8, the CPU 51 corrects the vehicle speed plan generated in S4 for the static driving trajectory after the dynamic driving trajectory has been reflected in S7, based on the contents of the reflected dynamic driving trajectory. Note that if the static driving trajectory generated in S3 remains unchanged as a result of reflecting the dynamic driving trajectory, the processing of S8 may be omitted.

[0059] Next, in S9, the CPU 51 calculates control amounts for the vehicle to travel on the static traveling trajectory generated in S3 (or the trajectory after reflection if the dynamic traveling trajectory has been reflected in S7) at a speed in accordance with the speed plan generated in S4 (or the revised plan if the speed plan has been revised in S8). Specifically, control amounts for the accelerator, brake, gear, and steering are calculated. Note that the processing of S9 and S10 may be performed by the vehicle control ECU 40 that controls the vehicle, rather than the navigation device 1.

[0060] Thereafter, in S10, the CPU 51 reflects the control amount calculated in S9. Specifically, the calculated control amount is transmitted to the vehicle control ECU 40 via the CAN. The vehicle control ECU 40 performs vehicle control of the accelerator, brake, gear, and steering based on the received control amount. As a result, driving assistance control is possible in which the vehicle travels along the static driving trajectory generated in S3 (or the trajectory after reflection if the dynamic driving trajectory has been reflected in S7) at a speed in accordance with the speed plan generated in S4 (or the revised plan if the speed plan has been modified in S8).

[0061] Next, in S11, the CPU 51 determines whether the vehicle has traveled a certain distance since the static travel trajectory was generated in S3. For example, the certain distance is set to 1 km.

[0062] Then, if it is determined that the vehicle has traveled a certain distance since the static travel trajectory was generated in S3 (S11: YES), the process returns to S1. After that, the static travel trajectory is generated again for a section within a predetermined distance from the current position of the vehicle along the planned travel route (S1 to S4). Note that in this embodiment, the static travel trajectory is repeatedly generated for a section within a predetermined distance from the current position of the vehicle along the planned travel route every time the vehicle travels a certain distance (for example, 1 km), but if the distance to the destination is short, the static travel trajectory to the destination may be generated all at once at the start of travel.

[0063] On the other hand, if it is determined that the vehicle has not traveled a certain distance since the static driving trajectory was generated in S3 (S11: NO), it is determined whether or not to end assisted driving by autonomous driving assistance (S12). Assisted driving by autonomous driving assistance can be ended not only when the vehicle has arrived at the destination, but also when the user intentionally cancels (overrides) the assisted driving by autonomous driving assistance by operating an operation panel provided in the vehicle, or by operating the steering wheel or brakes.

[0064] If it is determined that the assisted driving by the autonomous driving assistance should be ended (S12: YES), the autonomous driving assistance program is ended. On the other hand, if it is determined that the assisted driving by the autonomous driving assistance should be continued (S12: NO), the process returns to S5.

[0065] Next, the sub-processing of the static traveling trajectory generation process executed in S3 will be described with reference to Fig. 7. Fig. 7 is a flowchart of the sub-processing program of the static traveling trajectory generation process.

[0066] First, in S21, the CPU 51 acquires the current position of the vehicle detected by the current position detection unit 31. It is desirable to identify the current position of the vehicle in detail using, for example, high-precision GPS information or high-precision location technology. Here, high-precision location technology is a technology that detects white lines and road paint information captured by a camera installed in the vehicle using image recognition, and further compares the detected white lines and road paint information with, for example, high-precision map information 15, thereby making it possible to detect the traveling lane and the vehicle position with high precision. Furthermore, if the vehicle is traveling on a road with multiple lanes, the lane in which the vehicle is traveling is also identified.

[0067] Next, in S22, the CPU 51 acquires information such as lane shape, lane marking information, intersection information, and toll gate information for the section (e.g., a secondary mesh including the vehicle's current position) ahead of the vehicle's direction of travel for which a static driving trajectory is to be generated, based on the high-precision map information 15 acquired in S2. The lane shape and lane marking information acquired in S22 include the number of lanes, lane width, where and how the number of lanes increases or decreases if any, traffic divisions in the direction of travel for each lane, and road connections (specifically, the correspondence between lanes included in the road before passing a branch point and lanes included in the road after passing the branch point). Furthermore, the toll gate information includes gate information regarding gates installed at the toll gate, including information regarding the number of gates, gate locations (including information specifying the locations of the gate entrances and exits, and information specifying the correspondence between the gates and lanes before and after the toll gate), and gate type (general-only, ETC-only, or general ETC-compatible). The intersection information includes information regarding the intersection shape as well as the location and shape of features located at the intersection. Furthermore, "features placed at intersections" include road markings painted on the road surface, such as guiding lines (white guide lines) and diamond-shaped guidance strips (diamond marks) placed in the center of intersections, as well as structures such as poles.

[0068] As mentioned above, the static driving trajectory generation process generates a static driving trajectory for an area that includes at least the area outside the detection range where road conditions around the vehicle can be detected by the exterior camera 39 or other sensors, and therefore information about toll gates that are located further ahead than the detection range from the vehicle's position and that the vehicle must pass through is also obtained.

[0069] Next, in S23, the CPU 51 constructs a lane network for the section ahead of the vehicle in the direction of travel for which a static driving trajectory is to be generated, based on the lane shape, lane marking information, and tollgate information (including gate information) acquired in S22. Here, the lane network is a network that indicates the lane movement that the vehicle can select.

[0070] Here, as an example of constructing a lane network in S23, a case where a vehicle travels along the planned travel route shown in FIG. 8 will be described. The planned travel route shown in FIG. 8 is a planned travel route, particularly when passing through a toll gate, in which the vehicle travels straight from the current position of the vehicle, merges with a road coming from the right at the next branch point 71, passes through toll gate 72 with four gates A to D, and continues onto a road that branches off to the right at the next branch point 73. In the planned travel route shown in FIG. 8, for example, after merging with a road coming from the right at branch point 71, it is possible to enter the right lane, or to continue on the left lane. In addition, there are four gates A to D at the toll gate, and it is possible to enter the gate located in a position where the vehicle travels straight from the current lane, or to change lanes and enter another gate. Furthermore, it is possible to enter the right lane or the left lane after passing through toll gate 72. However, at the next junction 73, it is necessary to proceed onto a road that branches off to the right, so it is necessary to change lanes to the right lane before entering junction 73. Figure 9 shows a lane network constructed for a section where such lane changes are possible.

[0071] As shown in Figure 9, the lane network divides the section that generates the static driving trajectory ahead of the vehicle's direction of travel into multiple sections (groups). Specifically, the positions of branch points, positions where lanes increase or decrease, points where lane markings disappear before the toll gate, points where lane markings resume after passing through the toll gate, gate entrances, and gate exits are used as boundaries to divide the section. Node points (hereinafter referred to as lane nodes) 75 are set for each lane (within the toll gate, gates correspond to lanes) located on the boundary of each divided section. Furthermore, links (hereinafter referred to as lane links) 76 that connect the lane nodes 75 are set.

[0072] Furthermore, the lane network includes information that specifies the correspondence between the lanes included in the road before the junction and the lanes included in the road after the junction, that is, the lanes that can be moved after the junction relative to the lanes before the junction, by connecting the lane nodes and lane links at the junction in particular. Specifically, it indicates that a vehicle can move between the lanes that correspond to the lane nodes that are connected by lane links between the lane nodes that are set on the road before the junction and the lane nodes that are set on the road after the junction.

[0073] To generate such a lane network, the high-precision map information 15 stores lane flags indicating the correspondence between lanes for each combination of roads entering and exiting the branch point for each road connected to the branch point. For example, FIG. 10 shows lane flags for entering the branch point from the left road and exiting onto the upper road, and lane flags for entering the branch point from the right road and exiting onto the upper road. The lane flags set to "1" for lanes included in the road before the branch point correspond to those for lanes included in the road after the branch point, i.e., the lanes are movable before and after the branch point. When constructing the lane network at S23, the CPU 51 references the lane flags to form connections between lane nodes and lane links at the branch point.

[0074] Furthermore, the lane network includes information that identifies the correspondence between the lanes included in the road in front of the gate and the gate, that is, the gates that can be entered for the lanes included in the road in front of the gate, by connecting the lane nodes and lane links at the entrances to the gates in particular. For example, in the example shown in Figure 9, the road in front of the gate has two lanes on each side, and indicates that either the left lane or the right lane can enter any of gates A to D.

[0075] Similarly, the lane network also includes information specifying the correspondence between the lanes included in the road after passing through the gate and the gate, that is, the lanes that can be entered on the road that is traveled after passing through the gate, by connecting the lane nodes and lane links at the exit of the gate in particular. For example, in the example shown in Figure 9, the road after passing through the gate has two lanes on each side, and indicates that either the left lane or the right lane can be entered from any of gates A to D.

[0076] It should be noted that the above-mentioned lane network is not constructed by the navigation device 1 in S23, but rather the server device 4 may possess a lane network constructed in advance for the entire country, and the lane network for the relevant section may be obtained from the server device 4 in S23.

[0077] Next, in S24, the CPU 51 sets a start lane (start position) from which the vehicle will start moving, relative to the lane node located at the start point of the lane network constructed in S23, and sets a target lane (target position) to which the vehicle will move, relative to the lane node located at the end point of the lane network. If the start point of the lane network is a road with multiple lanes in each direction, the lane node corresponding to the lane in which the vehicle is currently located becomes the start lane. On the other hand, if the end point of the lane network is a road with multiple lanes in each direction, the lane node corresponding to the leftmost lane (for left-hand traffic) becomes the target lane.

[0078] Then, in S25, the CPU 51 references the lane network constructed in S23, searches for a route that connects the start lane to the target lane, and derives multiple candidate routes for lane movement patterns (hereinafter referred to as candidate routes). For example, the route is searched for from the target lane side using Dijkstra's algorithm. However, search methods other than Dijkstra's algorithm may be used as long as they can search for a route that connects the start lane to the target lane. One method for searching candidate routes is to derive, for example, one route that connects the start lane to the target lane (hereinafter referred to as a reference route), and then derive another route that connects the start lane to the target lane based on the reference route. For example, if the reference route is traced from the start lane side and a section or branch point where a lane change is possible is reached, a new route different from the reference route is generated by branching off. The reference route and the other derived routes are then combined to form candidate routes.

[0079] Furthermore, when deriving candidate routes in S25, especially for sections that pass through toll gates, the gates that the vehicle can pass through within the toll gate are identified in advance based on the gate information acquired in S22, and only routes that pass through passable gates are considered candidate routes. For example, closed gates and ETC-only gates for vehicles not equipped with ETC are considered to be gates that cannot be passed through.

[0080] 11 and 12 show a list of candidate routes derived from the lane network shown in FIG. 9. In the examples shown in FIGS. 11 and 12, Gate A is a gate that the vehicle cannot pass through. As a result, there are a total of 12 candidate routes. In the following explanation, the 12 candidate routes shown in FIGS. 11 and 12 will be identified and referred to as candidate routes 1 to 12, in order.

[0081] Thereafter, in S26, the CPU 51 executes lane change position setting processing. Here, the lane change position setting processing is processing for setting specific lane change positions (hereinafter referred to as lane change positions) for routes involving lane changes among the candidate routes generated in S25. Note that the lane change positions are set for each candidate route at positions that are estimated to have the lowest cost in the cost calculation (S28) described below. The lane change position setting processing in S26 will be described in detail below.

[0082] First, in S26, the CPU 51 sets a recommended position (hereinafter referred to as the recommended lane-change position) for lane changes made to pass through a toll gate or branch point (excluding lane changes made within the toll gate, i.e., between the point where the lane markings disappear before the toll gate and the point where the lane markings resume after passing through the toll gate). Specifically, the recommended lane-change position is set a predetermined distance before the toll gate or branch point where the lane change is to be made. Note that the predetermined distance can be set appropriately based on, for example, the road type, but for expressways it is set to, for example, 300 m. Then, for lane changes made to pass through a toll gate or branch point, the lane-change position is set so that the lane change begins as close as possible to the recommended lane-change position. For example, candidate route 1 is a route in which the driver changes lanes to the right lane in order to pass through junction 73 within section A just before junction 73, as shown in Figure 13. As shown in Figure 13, the recommended lane change position 300 m before junction 73 exceeds section A in which lane change positions can be set, so lane change position 77 is set to the nearest position within section A that is as close as possible to the recommended lane change position.

[0083] On the other hand, for lane changes made within the toll gate, i.e., between the point where the dividing line disappears before the toll gate and the point where the dividing line reappears after passing through the toll gate, the CPU 51 sets the lane change position so that the lane change begins as far away as possible from the entrance or exit of the gate. For example, candidate route 1 is a route in which, as shown in Figure 13, the vehicle changes lanes to the left within section B from the point where the dividing line disappears just before toll gate 72 to the entrance to gate B of toll gate 72, and then changes lanes to the right within section C from the exit of gate B of toll gate 72 to the point where the dividing line resumes after passing through the toll gate. Therefore, lane change positions 77 are set at the nearest position in section B and the furthest position in the direction of travel in section C.

[0084] The lane change position set for the candidate route in S26 is set taking into consideration the required lane change distance. That is, the lane change position includes both a lane change start point where the lane change begins and a lane change end point where the lane change ends, and the distance between them is the required lane change distance. The required lane change distance is calculated using map information, vehicle information, etc. For example, the lateral acceleration (lateral G) generated when the vehicle changes lanes is calculated from the vehicle speed (assuming the speed limit of the road) and lane width. A clothoid curve is used to calculate a trajectory that is as smooth as possible and minimizes the distance required for the lane change, provided that the lateral G does not exceed an upper limit (e.g., 0.2 G) that does not interfere with the automated driving assistance and does not cause discomfort to the vehicle occupants. The clothoid curve is the curve traced by the vehicle when the vehicle travels at a constant speed and the steering wheel is turned at a constant angular velocity. The required lane change distance is then calculated based on the calculated trajectory.

[0085] Next, in S27, the CPU 51 adds lane nodes 75 to the lane change positions set in S26 for the candidate route generated in S25. Here, the lane change positions include the lane change start point where the lane change begins and the lane change end point where the lane change ends, as described above. In S28, lane nodes 75 are added for each of the lane change start point and lane change end point. In addition, lane links 76 connecting the lane nodes 75 are also added in conjunction with the addition of lane nodes. Furthermore, lane links other than the lane change positions are basically straight (shaped along the lanes). As a result, as shown in FIG. 14, the candidate route indicates a more detailed lane movement pattern that identifies the lane change positions set in S26. Note that if the candidate route generated in S25 is a route that does not include any lane changes, the processing of S27 may be omitted.

[0086] Next, in S28, the CPU 51 calculates the total cost for each of the candidate routes generated in S25, with lane change positions set in S26, and with lane nodes and lane links added in S27, taking into account the set lane change positions.The CPU 51 then compares the total cost values ​​for each route and identifies the candidate route with the smallest total cost value as the lane movement mode of the vehicle that is recommended for vehicle movement.

[0087] Here, the cost is the sum of the "lane cost," "lane change position cost," and "gate cost." In S28, the total values ​​of all lane costs, lane change position costs, and gate costs are calculated for each candidate route and compared.

[0088] First, regarding "lane cost," a lane cost is assigned to each lane link 76. The lane cost assigned to each lane link 76 is based on the length of the lane link 76 or the time required for movement. In particular, in this embodiment, the length of the lane link (in meters) is used as the reference value for the lane cost. For lane links involving lane changes, a predetermined cost per lane change (e.g., 50) is added to the reference value. For lane links on roads consisting of multiple lanes, the reference value is multiplied by a coefficient depending on the position of the lane being traveled. Specifically, the lane cost of a lane link in an overtaking lane is adjusted to be higher than that of a lane link in a driving lane. As a result, the longer the distance traveled in the overtaking lane, the higher the total lane cost calculated, making it less likely that the route will be selected as a recommended lane movement mode. Therefore, routes with shorter distances traveled in the overtaking lane are preferentially selected as recommended lane movement modes. For roads without a division into driving lanes and passing lanes, in countries where traffic drives on the left, the lane cost is adjusted so that the lane link traveling in the lane located on the right side has a higher lane cost. However, within the toll gate, that is, from the point where the dividing line disappears before the toll gate to the point where the dividing line resumes after passing the toll gate, the cost adjustment due to the passing lane is not performed. Furthermore, lane links 76 in the same gate are basically considered to have the same length (i.e., the increase in distance due to lane changes is ignored). Furthermore, the length of lane links 76 within an intersection is considered to be 0 or a fixed value. Then, the total value of the lane costs of all the lane links 76 included in the candidate route is calculated as the lane cost of the candidate route.

[0089] Next, the "lane change position cost" will be explained. The lane change position cost is calculated under the following conditions (A) to (C). (A) First, if the candidate route for which costs are to be calculated includes a lane change required to pass through a toll gate or branch point, the CPU 51 sets a recommended lane change position recommended for the lane change. The method for setting the recommended lane change position is the same as in S26 above, where the recommended lane change position is set a predetermined distance before the target toll gate or branch point for the lane change. The predetermined distance can be set appropriately based on, for example, the road type, but for expressways, it is set to, for example, 300 m. Then, assuming that the distance from the target toll gate or branch point to the recommended lane change position is L1 and the distance from the target toll gate or branch point to the lane change position set in S26 (more specifically, the lane change start point) is X1, the CPU 51 calculates the lane change position cost C1 using the following formula (1): C1 = |1-X1 / L1| × K1 (constant) (1) The value of K1 can be set appropriately, for example, to 50. For a route that includes multiple lane changes, the lane change position cost C1 is calculated for each included lane change. For example, as shown in Figure 15, a method for calculating the lane change position cost C1 will be explained using candidate route 1, which involves one lane change to the left before toll gate 72 to pass through toll gate 72, and a second lane change to the right before branch point 73 after passing toll gate 72 to pass through branch point 73. In the example shown in Figure 15, for the first lane change, the distance from toll gate 72 to the lane change position is 100 m, and the distance from toll gate 72 to the recommended lane change position is 300 m, so the lane change position cost C1 is 33.3. For the second lane change, the distance from branch point 73 to the lane change position is 180 m, and the distance from branch point 73 to the recommended lane change position is 300 m, so the lane change position cost C1 is 20. For the third lane change, the distance from junction 73 to the lane change position is 150 m, and the distance from junction 73 to the recommended lane change position is 300 m, so the lane change position cost C1 is 25. In other words, the lane change position cost C1 for candidate route 1 is the sum of these, or 78.3. According to formula (1) above, the closer the lane change position set for the candidate route in S26 is to the recommended lane change position, the smaller the lane change position cost C1 will be, and therefore the route will be selected as the lane movement mode recommended with priority. Furthermore, the fewer the number of lane changes on a route, the smaller the added cost will be, and so the route will also be selected as the lane movement mode recommended with priority. (B) Next, the CPU 51 calculates the lane change position cost C2 for the candidate route for which the cost is to be calculated, using the following formula (2), especially when the route includes a lane change between the gate exit and the point where the lane lines resume after passing through the toll gate. Let L2 be the distance from the gate exit to the point where the lane lines resume after passing through the toll gate, and X2 be the distance from the point where the lane lines resume after passing through the toll gate to the lane change position set in S26 (more specifically, the lane change start point). C2 = (X2 / L2) × K2 (constant) (2) The value of K2 can be set as appropriate, for example, to 50. For routes that include multiple lane changes between the gate exit and the point where the lane markings resume after passing through the toll gate, the lane change position cost C2 is calculated for each included lane change. On the other hand, for routes that do not include lane changes between the gate exit and the point where the lane markings resume after passing through the toll gate, C2 = 0. For example, as shown in FIG. 16, a method for calculating the lane change position cost C2 will be described using candidate route 1, in which the driver changes lanes to the right from the exit of gate B of toll gate 72 to the point where the lane markings resume after passing through the toll gate. In the example shown in FIG. 16, the distance from the gate exit to the point where the lane markings resume after passing through the toll gate is 100 m, and the distance from the point where the lane markings resume after passing through the toll gate to the lane change position is 30 m (corresponding to the required lane change distance), so the lane change position cost C2 is 15. According to formula (2) above, if a lane change is set on the exit side of the toll gate for the candidate route in S26, the farther the lane change position is from the gate exit, the smaller the lane change position cost C2, and therefore the route will be selected as the lane movement mode that is recommended with priority. Furthermore, the fewer lane changes a route has within the toll gate, the smaller the added cost will be, and therefore the route will also be selected as the lane movement mode that is recommended with priority. (C) Furthermore, for a candidate route for which costs are to be calculated, especially when a lane change is made between the point where the dividing line before the toll gate disappears and the entrance to the gate, the CPU 51 calculates a lane change position cost C3 using the following formula (3): L3 is the distance from the point where the dividing line before the toll gate disappears to the entrance to the gate, and X3 is the distance from the point where the dividing line before the toll gate disappears to the lane change position set in S26 (more specifically, the lane change start point). C3 = (X3 / L3) × K3 (constant) (3) The value of K3 can be set as appropriate, for example, to 50. For routes that include multiple lane changes between the point where the dividing line disappears before the toll gate and the entrance to the gate, the lane change position cost C3 is calculated for each included lane change. On the other hand, for routes that do not include lane changes between the point where the dividing line disappears before the toll gate and the entrance to the gate, C3 = 0. For example, as shown in FIG. 16, a method for calculating the lane change position cost C3 will be described using candidate route 1, in which the driver changes lanes to the left from the point where the lane markings disappear before the toll gate 72 to the entrance to gate B of the toll gate 72. In the example shown in FIG. 16, the distance from the point where the lane markings disappear before the toll gate to the entrance to the gate is 100 m, and the distance from the point where the lane markings disappear before the toll gate to the lane change position is 0 m, so the lane change position cost C3 is "0." According to formula (3) above, if the candidate route includes a lane change set on the entrance side of the toll gate in S26, the farther the lane change position is from the entrance to the gate, the smaller the lane change position cost C3 will be, and therefore the route will be selected as the lane movement mode that is recommended with priority. Furthermore, the fewer lane changes within the toll gate, the smaller the added cost will be, and the route will also be selected as the lane movement mode that is recommended with priority.

[0090] Then, the total value of the lane change position costs C1 to C3 calculated for all lane changes included in the candidate route is calculated as the lane change position cost of that candidate route. Incidentally, when comparing the above formulas (2) and (3), if the distance L2 from the disappearance point of the lane line on the side before the toll gate to the entrance of the gate is longer than the distance L3 from the exit of the gate to the restart point of the lane line after passing through the toll gate (L2 > L3), the cost addition amount in formula (3) is larger than the cost addition amount in formula (2) (assuming X2 = X3 and K2 = K3). On the other hand, if the distance L3 from the disappearance point of the lane line on the side before the toll gate to the entrance of the gate is longer than the distance L2 from the exit of the gate to the restart point of the lane line after passing through the toll gate (L2 < L3), the cost addition amount in formula (2) is larger than the cost addition amount in formula (3) (assuming X2 = X3 and K2 = K3). That is, even when making a lane change within the same toll gate, a candidate route that makes a lane change in a wider section can make the lane change with more margin, so the cost is calculated to be smaller.

[0091] Finally, regarding the "gate cost", the gate cost is calculated under the following conditions (D) and (E). (D) First, when the candidate route for which the cost is to be calculated passes through the toll gate, the CPU 51 identifies the type of the gate to be passed based on the gate information acquired in S22. The types of gates include general dedicated, ETC dedicated, and general ETC dual-purpose. When the type of the gate to be passed is not the type of gate corresponding to the vehicle, the gate cost C4 is calculated by the following formula (4). Incidentally, the case where the type of the gate is not the type of gate corresponding to the vehicle means the case where a vehicle equipped with ETC passes through a general dedicated gate. C4 = total number of gates × K4 ····(4) The value of K4 can be set as appropriate, but for example, it may be 150, which is the total value of K1 to K3. When the type of gate being passed through is a gate of a type that corresponds to the vehicle, the gate cost C4 = 0. However, when a vehicle equipped with ETC passes through a gate that is also used for general ETC, the gate cost C4 may be added. According to the above formula (4), when passing through a gate of a type that corresponds to the vehicle, the gate cost C4 is smaller than when passing through a gate of a type that does not correspond to the vehicle, so this is selected as the lane movement mode that is recommended with priority. (E) First, if the candidate route for which costs are to be calculated passes through a toll gate, the CPU 51 identifies the correspondence between the lanes before the toll gate and the gate based on the gate information acquired in S22. Specifically, based on the positional relationship between each gate at the toll gate and the lanes before the toll gate, the CPU 51 classifies the gates into those that correspond to the lanes before the toll gate (hereinafter referred to as corresponding gates) and those that do not correspond to the lanes before the toll gate (hereinafter referred to as non-corresponding gates). For example, at toll gate 72 shown in Figure 16, gates C and D are corresponding gates because they are located in a position that continues from the lanes of the road before the toll gate (in a road-like relationship). On the other hand, gates A and B are located in the position of a lane newly added at the toll gate and are not in a position that continues from the lanes of the road before the toll gate (not in a road-like relationship), so they are non-corresponding gates. If the candidate route for which costs are to be calculated includes lane changes made between the point where the dividing line disappears before the toll gate and the entrance to the gate, and if the driver passes through a compatible gate, the lane change will be to a lane where there is a possibility of other vehicles being present behind, so a gate cost C5 of 5 will be added per lane change. On the other hand, if the driver passes through a non-compatible gate, the lane change will be to a lane where there is no risk of other vehicles being present behind, so no gate cost C5 will be added. On the other hand, if the candidate route for which costs are to be calculated includes lane changes made between the exit of the gate and the point where the dividing line resumes after passing through the toll gate, the lane change will be to a lane where there is a possibility of other vehicles being present behind, so a gate cost C5 of 5 will be added per lane change, regardless of whether the driver passes through a compatible gate or a non-compatible gate.

[0092] The gate cost of the candidate route is calculated as the sum of the gate costs C4 and C5 calculated for all toll gates that the candidate route passes through.

[0093] FIG. 17 is a diagram showing the total values ​​of the "lane cost," "lane change position cost," and "gate cost" calculated according to the above explanation for the 12 candidate routes 1 to 12 shown in FIGS. 11 and 12. In the example shown in FIG. 17, of gates A to D, gate A is closed, gate C is a general-use gate, and gates B and D are ETC-only gates. The vehicle is also assumed to be equipped with ETC. Comparing the total costs calculated for candidate routes 1 to 12 shown in FIG. 17, the total cost of candidate route 12 is the smallest at 801.5. Therefore, in S28, the CPU 51 identifies candidate route 12 as the recommended lane movement pattern for the vehicle when traveling along it.

[0094] Next, in S29, the CPU 51 calculates a recommended travel trajectory for the vehicle to move between lanes according to the candidate route selected in S28 (hereinafter referred to as the recommended route), particularly for the section for which the lane change position was set in S26. Note that if the recommended route selected in S28 is a route that does not involve any lane changes, the processing of S29 may be omitted.

[0095] Specifically, the CPU 51 calculates the driving trajectory using map information, etc., of the lane change position set in S26. For example, the CPU 51 calculates the lateral acceleration (lateral G) that occurs when the vehicle changes lanes from the vehicle speed (assuming the speed limit of the road) and the lane width, and calculates a trajectory that connects the lane change start point to the lane change end point as smoothly as possible using a clothoid curve, on the condition that the lateral G does not interfere with the automated driving assistance and does not exceed an upper limit value (e.g., 0.2 G) that does not cause discomfort to the vehicle occupants. Note that a clothoid curve is a curve that is traced by the vehicle when the vehicle travels at a constant speed and the steering wheel is turned at a constant angular velocity.

[0096] Then, in S30, the CPU 51 generates a specific driving trajectory for driving along the recommended route derived in S25 for sections other than the section where the lane change position is set. For example, when generating a driving trajectory for turning right or left at an intersection or changing lanes, the CPU 51 calculates the lateral acceleration (lateral G) acting on the vehicle and calculates a trajectory that connects the trajectories as smoothly as possible using a clothoid curve, provided that the lateral G does not exceed an upper limit (e.g., 0.2 G) that does not interfere with the automated driving assistance and does not cause discomfort to the vehicle occupants. Note that for sections that are not sections where a lane change is required or sections within an intersection, a trajectory that passes through the center of the lanes is set as the recommended driving trajectory for the vehicle. Then, by combining this with the driving trajectory calculated in S29, a static driving trajectory is generated, which is a driving trajectory recommended for the vehicle for roads included in the planned driving route.

[0097] The static driving trajectory generated in S29 and S30 is stored in the flash memory 54 or the like as assistance information to be used for automatic driving assistance. Then, the process proceeds to S4, where various driving assistance measures are carried out based on the generated static driving trajectory.

[0098] As described above in detail, the navigation device 1 and the computer program executed by the navigation device 1 according to this embodiment acquire a planned driving route along which the vehicle will travel (S1), acquire gate information, which is information about the location of toll gates at toll gates that are to be passed along the planned driving route and are located a predetermined distance or more ahead of the vehicle's position (S2), acquire candidate lane movement modes that the vehicle can select when passing through toll gates along the planned driving route using map information including lane shapes and the gate information (S25), calculate costs for the acquired candidate lane movement modes taking into account the lane change locations where the lane change will occur, and compare the calculated costs to select a lane movement mode for the vehicle recommended for passing through the toll gate from among the candidate lane movement modes (S28), thereby making it possible to appropriately select in advance a lane movement mode for performing a recommended lane change when passing through a toll gate. As a result, it is possible to prevent unrecommended lane changes while the vehicle is traveling and to appropriately provide driving assistance. In addition, a recommended driving trajectory for driving on roads included in the planned driving route is generated in accordance with the recommended lane movement pattern of the vehicle (S3), and driving assistance for the vehicle is provided based on the generated driving trajectory (S9, S10).Therefore, when providing driving assistance to the vehicle, it is possible to provide assistance for the vehicle to drive in accordance with the lane movement pattern in which the recommended lane change is performed. In addition, using map information including lane shapes and gate information, a lane network is obtained, which is a network showing the lane movements that can be selected when the vehicle passes through a toll gate along the planned driving route (S23), a start position from which the vehicle begins to move and a target position to which the vehicle will move are set in the lane network (S24), and a route connecting the start position and the target position in the lane network is obtained as a candidate lane movement mode (S25).Therefore, by using the lane network, it is possible to appropriately obtain candidate lane movement modes that can be selected when the vehicle moves to the destination. In addition, the lane network divides the planned route into boundaries, each containing the location of a branch point, a location where lanes increase or decrease, a point where the dividing line disappears before the toll gate, a point where the dividing line resumes after passing through the toll gate, a gate entrance, and a gate exit. A node is set for each lane located on the boundary of each divided section, and the network is equipped with links connecting the set nodes. Therefore, by using the lane network, it is possible to appropriately obtain candidate lane movement patterns that the vehicle can select when traveling to its destination. Furthermore, among the candidate lane movement modes, for those that involve a lane change to pass through a toll gate or a branching point, a recommended position is set at a point a predetermined distance before the toll gate or branching point, and the further the lane change position is from the recommended position, the higher the cost calculated (S28). Therefore, it is possible to appropriately select a candidate lane movement mode that performs a lane change at a position as close as possible to the position where the lane change is recommended as the lane movement mode in which the recommended lane change will be performed. Furthermore, among the candidates for lane movement mode, for candidates for lane movement mode involving a lane change between the disappearance point of the lane markings before the toll gate and the entrance of the gate, there is a first calculation condition that adds a higher cost the closer the distance from the lane change position where the lane change is made to the entrance of the gate, and a second calculation condition that adds a higher cost the closer the distance from the lane change position where the lane change is made to the exit of the gate for candidates for lane movement mode involving a lane change between the exit of the gate and the resumption point of the lane markings after passing through the toll gate, and the second calculation condition that adds a higher cost the closer the distance from the lane change position where the lane change is made to the exit of the gate for candidates for lane movement mode involving a lane change between the disappearance point of the lane markings before the toll gate and the entrance of the gate. If the distance to the point where the lane markings reappear is longer, the cost addition amount under the first calculation condition is greater than the cost addition amount under the second calculation condition, and if the distance from the point where the lane markings disappear before the toll gate to the entrance of the gate is longer than the distance from the exit of the gate to the point where the lane markings reappear after passing through the toll gate, the cost addition amount under the second calculation condition is greater than the cost addition amount under the first calculation condition.In other words, even when changing lanes within the same toll gate, it is possible to appropriately select a candidate lane movement mode in which the lane change is made over a wider section and at a location farther from the entrance / exit of the gate as the lane movement mode in which the recommended lane change will be made.

[0099] The present invention is not limited to the above-described embodiment, and it goes without saying that various improvements and modifications are possible within the scope of the present invention. For example, in this embodiment, driving assistance has been described particularly when passing through toll booths located at interchanges on expressways, but it can also be applied when passing through toll booths located at the entrances and exits of toll roads other than expressways, or toll booths located at the entrances and exits of facilities.

[0100] In addition, in this embodiment, in S28, the cost calculated for each candidate route is the sum of the "lane cost," "lane change position cost," and "gate cost." However, it is not necessary to calculate all of these costs; it is also possible to calculate the sum of only some of the costs and compare them between candidate routes.

[0101] In addition, in this embodiment, the static driving trajectory that is finally generated is information that identifies the specific trajectory (a set of coordinates or a line) on which the vehicle will travel, but it may also be information that does not identify the specific trajectory but is sufficient to identify the roads and lanes on which the vehicle will travel.

[0102] In addition, in this embodiment, the lane network is generated using the high-precision map information 15 (S23), but a lane network covering roads across the country may be stored in a DB in advance and read from the DB as needed.

[0103] Furthermore, in this embodiment, the high-precision map information stored in the server device 4 includes both information about the lane shape of the road (e.g., road shape, curvature, and lane width for each lane) and information about the dividing lines drawn on the road (e.g., center lines, lane boundaries, outer lane lines, guide lines, and guidance strips). However, the high-precision map information may include only information about the dividing lines, or may include only information about the lane shape of the road. For example, even if the high-precision map information includes only information about the dividing lines, it is possible to estimate information equivalent to the information about the lane shape of the road based on the information about the dividing lines. Furthermore, even if the high-precision map information includes only information about the lane shape of the road, it is possible to estimate information equivalent to the information about the dividing lines based on the information about the lane shape of the road. Furthermore, the "information about the dividing lines" may be information that identifies the type and arrangement of the dividing lines that divide the lanes, information that identifies whether lane changes are possible between adjacent lanes, or information that directly or indirectly identifies the shape of the lanes.

[0104] In addition, in this embodiment, as a means of reflecting the dynamic driving trajectory in the static driving trajectory, part of the static driving trajectory is replaced with the dynamic driving trajectory (S7), but instead of replacing it, the trajectory may be corrected so that the static driving trajectory approaches the dynamic driving trajectory.

[0105] In addition, in this embodiment, the vehicle control ECU 40 has been described as controlling all of the accelerator operation, brake operation, and steering operation, which are operations related to the vehicle's behavior, as autonomous driving assistance for automatically driving the vehicle without the user's driving operation. However, the autonomous driving assistance may also be defined as the vehicle control ECU 40 controlling at least one of the accelerator operation, brake operation, and steering operation, which are operations related to the vehicle's behavior, as part of the vehicle operations. On the other hand, manual driving performed by the user's driving operation will be described as the user performing all of the accelerator operation, brake operation, and steering operation, which are operations related to the vehicle's behavior, as part of the vehicle operations.

[0106] Furthermore, the driving assistance of the present invention is not limited to automatic driving assistance related to automatic driving of a vehicle. For example, it is possible to display the static driving trajectory generated in S3 or the dynamic driving trajectory generated in S6 on the navigation screen, and to provide guidance using voice, a screen, or the like (for example, guidance on lane changes, guidance on recommended vehicle speeds, etc.). Furthermore, the static driving trajectory or the dynamic driving trajectory may be displayed on the navigation screen to assist the user's driving operation.

[0107] Furthermore, in this embodiment, the automatic driving assistance program (FIG. 4) is configured to be executed by the navigation device 1, but it may also be configured to be executed by an in-vehicle device other than the navigation device 1 or the vehicle control ECU 40. In that case, the in-vehicle device or the vehicle control ECU 40 is configured to acquire the current position of the vehicle, map information, etc. from the navigation device 1 or the server device 4. Furthermore, the server device 4 may execute some or all of the steps of the automatic driving assistance program (FIG. 4). In that case, the server device 4 corresponds to the driving assistance device of the present application.

[0108] Furthermore, the present invention can be applied to devices other than navigation devices, such as mobile phones, smartphones, tablet devices, and personal computers (hereinafter referred to as mobile devices, etc.). It can also be applied to a system consisting of a server and a mobile device, etc. In that case, each step of the above-described automatic driving assistance program (see FIG. 4) may be implemented by either the server or the mobile device, etc. However, when applying the present invention to a mobile device, etc., a vehicle capable of executing automatic driving assistance and the mobile device, etc., must be connected to each other so that they can communicate (whether wired or wireless). [Explanation of symbols]

[0109] 1...navigation device, 2...driving assistance system, 3...information distribution center, 4...server device, 5...vehicle, 15...high-precision map information, 33...navigation ECU, 39...exterior camera, 40...vehicle control ECU, 51...CPU, 52...RAM, 53...ROM, 54...flash memory, 61...planned driving route, 71, 73...junction, 72...toll gate, 75...lane node, 76...lane link, 77...lane change position

Claims

1. a planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel; a gate information acquisition means for acquiring gate information which is information relating to the location of gates of toll gates to be passed through that are located ahead of the vehicle position by a predetermined distance or more on the planned driving route; a candidate acquisition means for acquiring candidates for lane movement modes that can be selected when the vehicle passes through the toll gate along the planned travel route, using map information including lane shapes and the gate information; a cost calculation means for calculating a cost for the lane change mode candidate acquired by the candidate acquisition means, taking into account a lane change position where a lane change is performed; a recommended movement mode selection means for comparing the costs calculated by the cost calculation means and selecting a lane movement mode of the vehicle recommended when passing through the toll gate from among the candidate lane movement modes, The candidate acquisition means Using map information including lane shapes and the gate information, a lane network is obtained, which is a network indicating lane movements that can be selected when the vehicle passes through the toll gate along the planned travel route; A start position from which the vehicle starts moving and a target position to which the vehicle moves are set with respect to the lane network; acquiring a route connecting the start position and the target position in the lane network as a candidate for the lane movement mode; The lane network is a driving assistance device that divides the planned driving route into sections with boundaries at branching points, locations where lanes increase or decrease, points where the dividing lines disappear before the toll gate, points where the dividing lines resume after passing through the toll gate, entrances to gates, and exits from gates, and sets nodes for each lane located on the boundary of each divided section, with links connecting the set nodes.

2. a travel trajectory generating means for generating a recommended travel trajectory for traveling on roads included in the planned travel route in accordance with the lane movement mode selected by the recommended movement mode selecting means; 2. The driving assistance device according to claim 1, further comprising: a driving assistance unit that provides driving assistance for the vehicle based on the driving trajectory generated by the driving trajectory generating unit.

3. a planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel; a gate information acquisition means for acquiring gate information which is information relating to the location of gates of toll gates to be passed through that are located ahead of the vehicle position by a predetermined distance or more on the planned driving route; a candidate acquisition means for acquiring candidates for lane movement modes that can be selected when the vehicle passes through the toll gate along the planned travel route, using map information including lane shapes and the gate information; a cost calculation means for calculating a cost for the lane change mode candidate acquired by the candidate acquisition means, taking into account a lane change position where a lane change is performed; a recommended movement mode selection means for comparing the costs calculated by the cost calculation means and selecting a lane movement mode of the vehicle recommended when passing through the toll gate from among the candidate lane movement modes, The cost calculation means Among the candidates for lane movement mode acquired by the candidate acquisition means, for the candidate for lane movement mode involving a lane change performed to pass through a toll gate or a branch point, a recommended position is set to a point a predetermined distance before the toll gate or the branch point; A driving assistance device that calculates a higher cost for the candidate lane movement pattern where the lane change position is located farther away from the recommended position.

4. a planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel; a gate information acquisition means for acquiring gate information which is information relating to the location of gates of toll gates to be passed through that are located ahead of the vehicle position by a predetermined distance or more on the planned driving route; a candidate acquisition means for acquiring candidates for lane movement modes that can be selected when the vehicle passes through the toll gate along the planned travel route, using map information including lane shapes and the gate information; a cost calculation means for calculating a cost for the lane change mode candidate acquired by the candidate acquisition means, taking into account a lane change position where a lane change is performed; a recommended movement mode selection means for comparing the costs calculated by the cost calculation means and selecting a lane movement mode of the vehicle recommended when passing through the toll gate from among the candidate lane movement modes, The cost calculation means a first calculation condition that, among the candidates for lane movement mode acquired by the candidate acquisition means, for a candidate for lane movement mode involving a lane change between a point where the division line on the front side of the toll gate disappears and an entrance to the gate, the closer the distance from the lane change position where the lane change occurs to the entrance to the gate, the higher the cost is added; a second calculation condition that, for a candidate lane movement mode that involves a lane change between the exit of a gate and the point where the demarcation lines resume after passing through a toll gate, among the candidates for the lane movement mode acquired by the candidate acquisition means, the closer the distance from the lane change position where the lane change occurs to the exit of the gate, the higher the cost that is added; If the distance from the exit of the gate to the point where the lane markings reappear after passing through the toll gate is longer than the distance from the point where the lane markings disappear before the toll gate to the entrance of the gate, the additional cost amount under the first calculation condition is greater than the additional cost amount under the second calculation condition, A driving assistance device in which, when the distance from the point where the dividing line disappears before the toll gate to the entrance of the gate is longer than the distance from the exit of the gate to the point where the dividing line resumes after passing through the toll gate, the cost addition amount under the second calculation condition is greater than the cost addition amount under the first calculation condition.

5. Computer, a planned driving route acquisition means for acquiring a planned driving route along which the vehicle will travel; a gate information acquisition means for acquiring gate information which is information relating to the location of gates of toll gates to be passed through that are located ahead of the vehicle position by a predetermined distance or more on the planned driving route; a candidate acquisition means for acquiring candidates for lane movement modes that can be selected when the vehicle passes through the toll gate along the planned travel route, using map information including lane shapes and the gate information; a cost calculation means for calculating a cost for the lane change mode candidate acquired by the candidate acquisition means, taking into account a lane change position where a lane change is performed; a computer program for causing the computer to function as a recommended movement mode selection means for selecting a lane movement mode of a vehicle recommended when passing through the toll gate from among the candidate lane movement modes by comparing the costs calculated by the cost calculation means, The candidate acquisition means Using map information including lane shapes and the gate information, a lane network is obtained, which is a network indicating lane movements that can be selected when the vehicle passes through the toll gate along the planned travel route; A start position from which the vehicle starts moving and a target position to which the vehicle moves are set with respect to the lane network; acquiring a route connecting the start position and the target position in the lane network as a candidate for the lane movement mode; The lane network is a computer program that divides the planned driving route into boundaries at the locations of branching points, locations where lanes increase or decrease, points where the dividing lines disappear before the toll gate, points where the dividing lines resume after passing through the toll gate, entrances to gates, and exits from gates, and sets nodes for each lane located on the boundary of each divided section, with links connecting the set nodes.

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