Route guidance method and route guidance device

Abstract

A controller (12) calculates, with respect to objects around a user, priorities with which the objects are used for route guidance to the user, selects an object for use in route guidance from among objects the priorities of which are greater than a predetermined priority threshold, performs route guidance by using the selected object, evaluates a degree of the user's understanding with respect to the route guidance using the selected object, and updates the priority of the object in accordance with a result of evaluation of the degree of understanding.

Description

[Technical Field]

[0001] The present invention relates to a route guidance method and a route guidance device. [Background technology]

[0002] A technology is known in which attributes are assigned to each of a plurality of landmarks and stored, the driving environment of the vehicle is recognized, a landmark from the plurality of landmarks that has been assigned an attribute suitable for the recognized driving environment is selected, and the selected landmark is used to guide the vehicle along its route. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-98800 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology disclosed in Patent Document 1, the attributes of the landmarks used for route guidance are predetermined for a specific driving environment, so even if the route guidance using landmarks actually provided to the user is incomprehensible to the user, there is a problem in that it is not possible to improve the understandability of the route guidance to suit the user.

[0005] The problem to be solved by the present invention is to provide a route guidance method and a route guidance device that can improve the ease of understanding of route guidance in accordance with the user. [Means for solving the problem]

[0006] The present invention solves the above problem by calculating the priority of using an object in route guidance for the user for objects around the user, selecting an object to be used for route guidance from among objects whose priority is greater than a predetermined priority threshold, providing route guidance using the selected object, evaluating the user's level of understanding of the route guidance using the object, and updating the priority for the object according to the evaluation result of the level of understanding. [Effects of the Invention]

[0007] According to the present invention, it is possible to improve the ease of understanding of route guidance in accordance with the user. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram of a route guidance system including a route guidance device according to an embodiment of the present invention. [Figure 2] FIG. 3 is a flowchart illustrating an example of a control procedure for executing a route guidance method according to an embodiment of the present invention. [Figure 3] FIG. 10 is a flowchart illustrating an example of a control procedure of a priority update method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the accompanying drawings. In this embodiment, a route guidance method and a route guidance device according to the present invention are applied to a route guidance system.

[0010] FIG. 1 is a block diagram of a route guidance system 100 including a route guidance device 10 according to this embodiment. As shown in FIG. 1, the route guidance system 100 includes a vehicle 1, a position acquisition device 2, an external sensor 3, an internal sensor 4, a database 5, a server 6, and a route guidance device 10. The position acquisition device 2, the external sensor 3, the internal sensor 4, the database 5, and the route guidance device 10 are mounted on the vehicle 1 and exchange information with each other via an in-vehicle network such as a CAN. In the route guidance system 100, the route guidance device 10 provides route guidance from the current location of the user to a destination to a user in the vehicle 1. The route guidance device 10 is, for example, a navigation device mounted on the vehicle 1. In this embodiment, the route guidance device 10 is described as an in-vehicle navigation device, but is not limited thereto, and may be a terminal device carried by the user. In other words, route guidance may be provided when the user is traveling on foot, bicycle, or the like without being in the vehicle 1.

[0011] The route guidance device 10 outputs guidance information to the user during route guidance. The guidance information includes, for example, a map and a route from the user's current location to the destination. Furthermore, when the user approaches a guidance point where route guidance is required, the route guidance device 10 outputs guidance information including the direction of travel at the guidance point to the user. A guidance point is, for example, a point where two or more routes can be entered, such as an intersection, a branch point, or an interchange on a highway. Even if the point does not have two or more routes, it can be set as a guidance point if it is needed to accurately guide the vehicle's direction of travel. In other words, the route guidance device 10 can determine and use, in advance, a point that can accurately guide the vehicle's direction of travel as a guidance point. The user drives the vehicle 1 according to the route guidance.

[0012] The position acquisition device 2 acquires the user's position information. In this embodiment, the position acquisition device 2 acquires the position information of the vehicle 1 as the user's position information. The position acquisition device 2 acquires the vehicle 1's position information from, for example, a GPS satellite. An example of the vehicle 1's position information is latitude and longitude information. The position acquisition device 2 acquires the position information from the GPS satellite at predetermined intervals. While the user is traveling in the vehicle 1, the user's position information changes as the vehicle 1 moves.

[0013] The external sensor 3 detects the surrounding environment including objects around the user. The external sensor 3 may be, for example, a camera installed in the vehicle 1, and may be a camera equipped with an imaging element such as a CCD or CMOS. The external sensor 3 acquires surrounding images capturing images of objects around the user. The objects are landmarks in the surrounding environment around the user. The objects include static objects and dynamic objects. Examples of static objects include advertising billboards, signs, stop lines, traffic lights, crosswalks, traffic restrictions, road trees, buildings, and road structures. Examples of road structures include bridges and tunnels. Static objects also include landmarks. Dynamic objects include, for example, automobiles (other vehicles) other than the user's vehicle, motorcycles, bicycles, pedestrians, and the like. The objects also include objects stored in map data and objects not stored in map data. Examples of objects stored in map data include landmarks such as convenience stores, restaurants, and gas stations. Objects that are not stored in the map data are, for example, static objects such as buildings and road structures, and dynamic objects such as automobiles (other vehicles) other than the vehicle itself.

[0014] The external sensor 3 detects the direction of an object around the user and the distance to the object. For example, the external sensor 3 is a millimeter-wave radar, a laser radar, an ultrasonic radar, a laser range finder, etc. The external sensor 3 also detects the relative speed (including the direction of movement) of the object with respect to the vehicle based on the change over time in the direction of the object and the distance to the object. Surrounding environment information including the surrounding environment detected by the external sensor 3 is output to the route guidance device 10 at predetermined intervals.

[0015] The interior sensor 4 detects the behavior and / or state of the user inside the vehicle. The interior sensor 4 may be, for example, a camera installed inside the vehicle 1, and may be a camera equipped with an imaging element such as a CCD or CMOS. The interior sensor 4, for example, continuously captures user images including the user's face. The interior sensor 4 performs image processing on the captured user images including the user's face and measures the user's line of sight. The interior sensor 4 may also detect the user's biological information. The user's biological information includes the user's heart rate, sweat, body temperature, and pulse rate. The interior sensor 4 may be, for example, a sensor provided in the interior camera, steering wheel, seat belt, or wearable device. The interior sensor 4 measures body temperature using a thermograph, a thermometer, or the like, and measures pulse rate, heart rate, and blood oxygen saturation using a wearable device such as a pulse oximeter. The interior sensor 4 may also be a microphone that captures the user's voice. The in-vehicle sensor 4 performs a voice recognition process on the acquired user voice to acquire the content of the user's speech. The detection information detected by the in-vehicle sensor 4 is output as user information to the route guidance device 10 at predetermined intervals.

[0016] The database 5 is a database that stores various types of information. The database 5 stores map information. The map information includes at least road information. The road information includes road types (e.g., general roads, toll roads, etc.) and the locations of intersections, stop lines, traffic lights, and road signs. The map information also includes information on landmarks such as convenience stores, restaurants, and gas stations. The map information also includes location information of guidance points that require route guidance.

[0017] The database 5 stores, for each object, information on an algorithm for calculating the priority of the object. When the controller 12 acquires an algorithm for calculating the priority of an object from the server 6 via the communication device 14, the controller 12 stores the acquired algorithm in the database 5. The algorithm stored in the database 5 is used by the controller 12 when calculating the priority of the object. The database 5 may also store information on the priority of the object. The priority is a ranking of objects in descending order of priority. The priority is updated each time the priority of an object is updated. The database 5 is not limited to storing the current priority after updating, but may also store historical information on priority within a certain period of time. The database 5 also stores guidance information used for route guidance. The guidance information includes, for example, basic guidance information including the direction in which the user should travel at a guidance point, and supplemental guidance information for identifying the guidance point using objects around the user. The basic guidance information is, for example, text such as, "Turn left soon."

[0018] The database 5 also stores vehicle information about the vehicle 1. The vehicle information includes driving information about the vehicle 1. The driving information about the vehicle 1 includes position information about the vehicle 1 and vehicle speed information about the vehicle 1. The position information about the vehicle 1 is updated at regular intervals. In this embodiment, the database 5 stores driving information about the vehicle 1 approaching a guidance point. If a destination is set for the vehicle 1, the vehicle information may also include information about the destination of the vehicle 1. The vehicle information also includes route information about the driving route set for the vehicle 1. The driving route is the driving route from the current position of the vehicle to the destination.

[0019] The server 6 is a device that manages information on a calculation method (algorithm) for calculating the priority of each object. The server 6 is a device accessible from multiple vehicles 1 and aggregates information on algorithms updated by the route guidance device 10 of each vehicle 1 and / or evaluation results of the user's understanding. The server 6 includes a database 61 and a communication device 62. The database 61 stores information on algorithms for calculating the priority of each object. The algorithms are updated and stored as appropriate based on information acquired from the route guidance device 10. For example, the server 6 updates the algorithm based on evaluation results of the user's understanding of the route guidance in each vehicle 1 and stores the updated algorithm in the database 61. The communication device 62 is a device that exchanges information with the route guidance device 10 via a network. The network refers to a telecommunications network such as the Internet or a LAN. The network is not particularly limited as long as it allows information to be exchanged between the route guidance device 10 and the server 6, and any known network can be used. The communication device 62 receives information on the algorithms updated by the controller 12 and evaluation results of the user's understanding from the route guidance device 10. The communication device 62 transmits information about the algorithm to the route guidance device 10.

[0020] The route guidance device 10 is a device that provides route guidance to a user to a destination. The route guidance device 10 includes an input device 11, a controller 12, an output device 13, and a communication device 14. In the route guidance device 10, the controller 12 acquires information from the position acquisition device 2, the outside-vehicle sensor 3, the inside-vehicle sensor 4, the database 5, the input device 11, and the communication device 14, generates guidance information based on the acquired information, and outputs the guidance information to the user via the output device 13, thereby providing the user with route guidance to the destination.

[0021] The input device 11 is an input interface that accepts input from the user. The input device 11 is composed of one or more devices. For example, the input device 11 is composed of a steering switch that the user can use to input, and a microphone that the user can use to input voice. The input device 11 may also be equipped with a touch panel or a keyboard. Information that the user inputs to the input device 11 is, for example, the user's destination.

[0022] Furthermore, the information input by the user to the input device 11 is user evaluation information including the user's evaluation of the route guidance using the object. For example, after route guidance using the object is output, the user inputs user evaluation information including an evaluation indicating whether or not the user understood the route guidance to the input device 11. Furthermore, the information input by the user to the input device 11 is desired information regarding the object. The user inputs the type of object that the user desires to use in route guidance to the input device 11 as desired information.

[0023] The output device 13 is an output interface that outputs route guidance based on the generated route. The output device 13 displays a map, the route generated by the route guidance device 10, the current location, etc. to the user on a screen, and also outputs the guidance information generated by the route guidance device 10 as audio. The output device 13 is composed of one or more devices. For example, the output device 13 is composed of a display that displays route guidance on a screen and a speaker that outputs audio data of the route guidance. Examples of displays include a liquid crystal panel and an organic EL panel. Note that when a touch panel display is used as the output device 13, it can also be used as the input device 11.

[0024] The communication device 14 is a device that exchanges information with a server 6 outside the vehicle 1 via a network. The communication device 14 receives information on an algorithm for calculating the priority of an object from the server 6. The communication device 14 transmits to the server 6 the evaluation result of the user's understanding and information on the algorithm updated by the controller 12.

[0025] The controller 12 includes a computer having hardware and software, and this computer includes a ROM storing a program, a CPU that executes the program stored in the ROM, and a RAM that functions as an accessible storage device. Note that, instead of or in addition to the CPU, an MPU, DSP, ASIC, FPGA, etc. can be used as the operating circuit.

[0026] 1, the controller 12 is configured to include, as functional blocks, an information acquisition unit 101, a priority calculation unit 102, a route guidance unit 103, and an evaluation unit 104, and executes each function through cooperation between software for executing each process and hardware. Note that in this embodiment, the functions of the controller 12 are divided into four blocks, and the functions of each functional block will be explained, but the functions of the controller 12 do not necessarily have to be divided into four blocks.

[0027] The information acquisition unit 101 acquires various types of information. The information acquisition unit 101 acquires, from the vehicle exterior sensor 3, surrounding environment information detected by the vehicle exterior sensor 3. The surrounding environment information includes image information of a surrounding image including a plurality of objects.

[0028] The information acquisition unit 101 acquires user information related to the user's behavior and / or state detected by the in-vehicle sensor 4 from the in-vehicle sensor 4. The user information includes, for example, user behavior information related to the user's behavior. For example, the user behavior information includes the user's eye movement and the user's speech content when the user approaches the guidance point. The user information also includes the user's biometric information when the user approaches the guidance point.

[0029] The information acquiring unit 101 acquires information input by a user. The information acquiring unit 101 acquires user evaluation information input by the user to the input device 11, the user evaluation information including the user's evaluation of route guidance using an object.

[0030] The information acquisition unit 101 acquires position information of an object on a map. For example, the information acquisition unit 101 identifies the position of the detected object from map information and / or a surrounding image. The information acquisition unit 101 also acquires position information of the user on the map from the position acquisition device 2.

[0031] The information acquisition unit 101 acquires driving correctness information indicating whether the user driving the vehicle 1 drove correctly in accordance with the route guidance. The information acquisition unit 101 compares the position of the vehicle 1 after the vehicle 1 has passed the guidance point with the route indicated by the route guidance, and if the position of the vehicle 1 after passing the guidance point is off the route, acquires driving correctness information indicating that the user did not drive the vehicle 1 correctly in accordance with the route guidance. If the position of the vehicle 1 after passing the guidance point is on the route, the information acquisition unit 101 acquires driving correctness information indicating that the user drove the vehicle 1 correctly in accordance with the route guidance.

[0032] The information acquisition unit 101 acquires driving information of the vehicle 1. For example, the information acquisition unit 101 acquires driving information of the vehicle 1 when the vehicle 1 approaches a guidance point from the database 5. The driving information is information including, for example, the position of the vehicle 1 and the vehicle speed of the vehicle 1. Alternatively, the information acquisition unit 101 may acquire the driving information directly from the vehicle 1.

[0033] The priority calculation unit 102 calculates a priority for using an object for route guidance among objects around the user. When the vehicle 1 approaches a guidance point while the vehicle 1 is traveling, the priority calculation unit 102 identifies objects located around the user from the surrounding environment information. For example, the priority calculation unit 102 performs image recognition processing on the surrounding image to identify one or more objects. The priority calculation unit 102 also acquires feature amounts of each of the multiple objects shown in the surrounding image and / or feature amounts between the multiple objects shown in the surrounding image. The priority calculation unit 102 also acquires feature amounts of the positions of the identified objects on a map. The priority calculation unit 102 also acquires feature amounts of the user's position on the map. The priority calculation unit 102 calculates the priority based on at least one of these feature amounts.

[0034] For example, the priority calculation unit 102 calculates the priority by using each feature amount as a quantitative index value for calculating the priority of the object. The index values ​​for calculating the priority of the object are the consistency of the object, the visibility of the object, the salience of the object, the uniqueness of the object, the proximity of the object to the guidance point, and the proximity of the object to the user's guidance point.

[0035] The priority calculation unit 102 calculates feature quantities indicating the consistency, visibility, and salience of an object as feature quantities of the object shown in the surrounding images. The feature quantity indicating consistency is, for example, the time that the object is shown in the surrounding images. The longer the time that the same object is shown in multiple consecutively captured surrounding images, the higher the consistency of the object is calculated to be. Furthermore, the consistency of an object that is ranked higher in priority and has a period longer than a predetermined period may be calculated to be higher than the consistency of an object that has a period shorter than the predetermined period.

[0036] A feature indicating visibility is, for example, the size of the area an object occupies in the surrounding image. For example, the closer an object is to the user, the larger the area the object occupies in the surrounding image, and therefore the higher the visibility is calculated. Furthermore, for the same distance from the user, the visibility of a truck, which is larger than a passenger car, is calculated to be higher than the visibility of a vehicle. Furthermore, the visibility of an object without any obstructions between the user and the object is calculated to be higher than the visibility of an object with an obstruction. A feature indicating saliency is the likelihood that an object will attract attention. Saliency is a value that evaluates the conspicuous characteristics of an object based on human visual characteristics. For example, the saliency of a red vehicle is calculated to be higher than the saliency of a gray vehicle. In this embodiment, the higher the values ​​of the consistency, visibility, and saliency of an object, the higher the priority of the object is calculated.

[0037] The priority calculation unit 102 calculates a feature quantity indicating the uniqueness of an object as a feature quantity between multiple objects shown in the surrounding image. The feature quantity indicating uniqueness is, for example, the degree of difference between the object and other objects around the object. For example, the difference is a difference in appearance or type. If a blue vehicle is present in a surrounding image that shows many white vehicles, the uniqueness of the blue vehicle is calculated to be higher than the uniqueness of the white vehicle. Also, if one bicycle is present in a surrounding image that shows many automobiles, the uniqueness of the bicycle is calculated to be higher than the uniqueness of the vehicle. In this embodiment, the higher the uniqueness of the object, the higher the priority of the object is calculated. In other words, the priority of an object that does not have overlapping features compared to other surrounding objects is calculated to be higher.

[0038] The priority calculation unit 102 calculates a feature amount indicating the proximity of the object to the guide point as a feature amount of the object's position on the map. The feature amount indicating the proximity of the object to the guide point is, for example, the distance between the position of the object and the position of the guide point. The priority of the object is calculated so that the closer the object is to the guide point, the higher the priority of the object. For example, if the guide point is an intersection, it is easier for the user to identify the intersection by using a building visible on the corner of the intersection as a landmark rather than a signboard visible a little further inside the intersection.

[0039] The priority calculation unit 102 calculates a feature quantity indicating the user's proximity to a guide point as a feature quantity of the user's position on the map. The feature quantity indicating the user's proximity to a guide point is, for example, the distance between the user's position and the guide point. In this embodiment, the weighting for each index value is changed depending on the user's proximity to the guide point. For example, if the distance between the user's position and the guide point is less than a predetermined distance, the weighting for saliency is calculated to be high, and if the distance between the user's position and the guide point is equal to or greater than the predetermined distance, the weighting for consistency is calculated to be high. The weighting will be described later.

[0040] The priority calculation unit 102 acquires an algorithm for calculating the priority of an object based on each index value related to the object from the server 6 via the communication device 14, and calculates the priority based on each index value and the algorithm. For example, the priority calculation unit 102 calculates the priority by adding up each index value based on the following formula (1).

number

[0041] Furthermore, the priority calculation unit 102 may calculate the priority based on user behavior information related to the user's behavior. The user's behavior is, for example, the movement of the user's line of sight when the vehicle 1 approaches a guidance point. The priority calculation unit 102 identifies an object that the user is gazing at based on the user's line of sight and surrounding environment information. The priority calculation unit 102 may calculate the priority of the identified object to be higher than the priorities of other objects. Furthermore, the priority calculation unit 102 may calculate the priority based on user input information. The user input information is desired information related to the object input by the user. Based on the desired information, the priority calculation unit 102 calculates the priority of an object of a type desired by the user to be higher than the priorities of objects of other types.

[0042] As described above, in this embodiment, the priority of an object is calculated based on the characteristics of the object around the user acquired from the external sensor 3, and an object with a priority greater than a predetermined priority threshold is used for route guidance. However, there are cases where the route guidance using the object actually provided to the user is incomprehensible to the user. Therefore, in this embodiment, when route guidance is provided to the user, the priority calculation unit 102 evaluates the user's understanding of the route guidance using the object and updates the priority of the object according to the evaluation result. For example, when the understanding level is high, the priority calculation unit 102 updates the priority to be higher than when the understanding level is low. This makes it more likely that objects with a high level of understanding by the user will be used for route guidance, thereby further improving the ease of understanding of route guidance.

[0043] The degree of understanding is expressed, for example, by two values: understood or not understood. The degree of understanding is evaluated by the evaluation unit 104. The method of evaluating the degree of understanding will be described later. In this embodiment, the priority calculation unit 102 compares the number of users who evaluated that they "understood" the route guidance using the same object with the number of users who evaluated that they "did not understand" the route guidance using the object, based on the evaluation results of the degrees of understanding of multiple users to whom route guidance using the same object has been output. When the number of users who evaluated that they "understood" is greater than the number of users who evaluated that they "did not understand," the priority calculation unit 102 calculates the priority of the object to be higher than when the number of users who evaluated that they "understood" is fewer than the number of users who evaluated that they "did not understand."

[0044] For example, the priority calculation unit 102 adjusts the weights a1 to a5 in the algorithm shown in equation (1). If the number of users who have rated "understood" is greater than the number of users who have rated "not understood", the priority calculation unit 102 adjusts the weights a1 to a5 so that the Score becomes larger. If the number of users who have rated "understood" is less than the number of users who have rated "not understood", the priority calculation unit 102 adjusts the weights a1 to a5 so that the Score becomes smaller. After adjusting the weights, the priority calculation unit 102 updates the algorithm to one that includes the adjusted weights and transmits the updated algorithm to the server 6.

[0045] Furthermore, when the evaluation unit 104 evaluates each of the multiple evaluation indexes as "understood" or "not understood," the priority calculation unit 102 may calculate a lower priority for a larger number of evaluation indexes evaluated as "not understood." Furthermore, the priority calculation unit 102 may transmit a control signal to the server 6 to update the algorithm based on the evaluation result of the user's understanding level.

[0046] The route guidance unit 103 provides route guidance so that the vehicle 1 travels along a travel route from the current position of the vehicle 1 to the destination. After acquiring the current position of the vehicle 1 and the user's destination, the route guidance unit 103 references map information stored in the database 5 and generates a travel route from the current position of the vehicle 1 to the destination. The route guidance unit 103 uses the location information acquired by the position acquisition device 2 as the current position of the vehicle 1. Furthermore, the route guidance unit 103 uses destination information input by the user via the input device 11 as the user's destination. The travel route may be a route that passes through multiple destinations. The route guidance unit 103 displays a map, the travel route, the current position of the vehicle 1, etc. on a screen for the user via the output device 13.

[0047] Furthermore, the route guidance unit 103 extracts guide points located on the travel route based on route information and map information of the travel route. Furthermore, when the vehicle 1 starts traveling along the travel route, the route guidance unit 103 periodically acquires the current position of the vehicle 1 and determines whether the vehicle 1 has approached the guide point based on the current position of the vehicle 1 and the position of the guide point on the travel route. For example, the route guidance unit 103 determines that the vehicle 1 has approached the guide point when the vehicle 1 arrives within a predetermined distance from the guide point. When the vehicle 1 has approached the guide point, the route guidance unit 103 outputs guidance information for the guide point to the output device 13. For example, the route guidance unit 103 may cause the output device 13 to output the generated guidance information as voice, or may display text or an icon such as an arrow on the screen indicating the direction in which the user should travel.

[0048] The guidance information is generated by the route guidance unit 103. The route guidance unit 103 generates guidance information necessary for the vehicle 1 to move along the travel route at a guidance point. The guidance information includes, for example, basic guidance information including the direction in which the user should move at the guidance point, and supplemental guidance information for specifying the guidance point using objects around the user. The supplemental guidance information is, for example, information for specifying the guidance point using objects as landmarks.

[0049] The route guidance unit 103 selects an object to be used for route guidance at a guidance point based on the priority of the object. The priority of the object is a value calculated by the priority calculation unit 102 for each object around the user when the vehicle 1 approaches the guidance point. The route guidance unit 103 compares the priority of each object with a predetermined priority threshold, and selects an object whose priority is greater than the predetermined priority threshold as an object to be used for route guidance. The route guidance unit 103 generates supplemental guidance information using the selected object.

[0050] Furthermore, the route guidance unit 103 may preset the number of objects to be used for route guidance as an object number threshold. When the number of objects whose priorities exceed a predetermined priority threshold is equal to or less than the predetermined object number threshold, the route guidance unit 103 selects all objects whose priorities exceed the predetermined priority threshold as objects to be used for route guidance. When the number of objects whose priorities exceed the predetermined priority threshold is greater than the predetermined object number threshold, the route guidance unit 103 randomly selects, from among the objects whose priorities exceed the predetermined priority threshold, objects equal in number to the predetermined object number threshold as objects to be used for route guidance.

[0051] An example of route guidance using objects will now be described. This example of route guidance will be described using an example in which the guidance point is an intersection located ahead of vehicle 1 and vehicle 1 needs to turn left at the intersection. When vehicle 1 approaches the intersection, route guidance device 10 recognizes objects around the user. Assume that the recognized objects are a convenience store, a post office, a blue preceding vehicle, and a signboard. The route guidance device 10 calculates a priority for each object and determines the order of priority from highest to lowest. For example, the order of priority is assumed to be convenience store, post office, preceding vehicle, and signboard from top to bottom. The route guidance device 10 also compares the priority of each recognized object with a predetermined priority threshold. For example, assume that the convenience store is the only object whose priority is greater than the predetermined priority threshold. In this case, the route guidance device 10 selects the convenience store as the object to be used for route guidance and generates guidance information including information for identifying an intersection using the convenience store as a landmark. For example, the route guidance device 10 generates guidance information by combining a text "Turn left soon" with a text "You will soon come to an intersection where you can see a convenience store." Then, the route guidance unit 103 causes the output device 13 to output the generated text "Turn left soon. You will soon come to an intersection where you can see a convenience store" in the form of an image and a sound.

[0052] As another example, a case will be described in which the objects having priorities greater than a predetermined priority threshold are the top three priorities: a convenience store, a post office, and a blue preceding vehicle. In this case, when the predetermined object number threshold is one, the route guidance device 10 randomly selects one from the three objects: the convenience store, the post office, and the blue preceding vehicle. When the convenience store is selected, the route guidance device 10 outputs text such as, "Turn left soon. You will reach an intersection where you can see the convenience store." When the post office is selected, the route guidance device 10 outputs text such as, "Turn left soon. You will reach an intersection where you can see the post office." When the blue preceding vehicle is selected, the route guidance device 10 outputs text such as, "Turn left soon. Please follow the blue vehicle ahead."

[0053] As described above, in this embodiment, the object with the highest priority is not necessarily selected as the object to be used for route guidance, but objects exceeding a predetermined priority threshold are randomly selected for route guidance. By providing route guidance to the user using a variety of objects to be used for route guidance, an opportunity to update the priority to suit the user can be provided. For example, suppose that a convenience store is the object with the highest priority, but a post office with the second highest priority is selected randomly. If route guidance using a post office is evaluated as being easy to understand for many users, the route guidance device 10 can calculate the priority so that the convenience store and post office are swapped.

[0054] The evaluation unit 104 evaluates the user's level of understanding of the route guidance using the object. The level of understanding is explained as a binary value of whether or not the user understood, but is not limited to this and may be expressed as a multi-level evaluation of three or more levels. The evaluation unit 104 evaluates whether or not the user understood the route guidance using the object, using the user's behavior and / or state when the route guidance using the object is output as an evaluation index. For example, if the user was unable to drive the vehicle 1 according to the route guidance, if the user behaved or appeared to be hesitant when approaching a guidance point, or if there was an input indicating that the user did not understand the route guidance, the evaluation unit 104 evaluates that the user did not understand the route guidance using the object.

[0055] The evaluation unit 104 evaluates the level of understanding based on driving correctness information indicating whether the user drove the vehicle 1 correctly in response to the route guidance. If the user did not drive the vehicle 1 correctly in response to the route guidance based on the driving correctness information, the evaluation unit 104 evaluates that the user "did not understand" the route guidance using the object. If the user drove the vehicle 1 correctly in response to the route guidance based on the driving correctness information, the evaluation unit 104 evaluates that the user "understood" the route guidance using the object.

[0056] Furthermore, the evaluation unit 104 evaluates the level of understanding based on driving information when the vehicle 1 approaches the guidance point. For example, the evaluation unit 104 determines whether the vehicle 1 braked suddenly or drove slower than normal before the guidance point based on the vehicle speed of the vehicle 1 when the vehicle 1 approached the guidance point. Driving slower than normal means driving at a speed slower than the slow speed when entering an intersection, for example, driving at less than 5 km / h. If the vehicle 1 braked suddenly or drove slower than normal before the guidance point, the evaluation unit 104 evaluates that the user "did not understand" the route guidance using the object. If the vehicle 1 did not brake suddenly or drove slower than normal before the guidance point, the evaluation unit 104 evaluates that the user "understood" the route guidance using the object. This is because if the user is unable to identify the guidance point and is hesitant, vehicle 1 is likely to brake suddenly or drive at an extremely slow speed just before the guidance point, and if vehicle 1 behaves in this way, it can be determined that the user does not understand the route guidance using the object.

[0057] Furthermore, the evaluation unit 104 evaluates the level of understanding based on the user's biometric information when the user approaches the guidance point. If the user's body temperature, pulse rate, heart rate, and / or sweat rate are elevated based on the biometric information, the evaluation unit 104 evaluates that the user "does not understand" the route guidance using the object. If the user's body temperature, pulse rate, heart rate, and / or sweat rate are not elevated, the evaluation unit 104 evaluates that the user "understands" the route guidance using the object. This is because if the user hesitates because they cannot identify the guidance point when approaching the guidance point, anxiety or stress will occur, and if it can be inferred from the user's biometric information that the user is in such a state, it is considered that the user does not understand the route guidance using the object.

[0058] The evaluation unit 104 also evaluates the level of understanding based on the user's behavior when the user approaches a guidance point. For example, based on the user behavior information, if the user's gaze moves left and right, the evaluation unit 104 evaluates that the user "does not understand" the route guidance using the object. If the user's gaze does not move left and right, the evaluation unit 104 evaluates that the user "understands" the route guidance using the object. This is because if the user hesitates when approaching a guidance point because they cannot identify the guidance point, the user's gaze is likely to move left and right to check their surroundings. Furthermore, based on the content of the user's utterance, if the evaluation unit 104 hears an utterance indicating that the user does not understand the guidance point, the evaluation unit 104 evaluates that the user "does not understand" the route guidance using the object. If the evaluation unit 104 hears no utterance indicating that the user does not understand the guidance point based on the content of the user's utterance, the evaluation unit 104 evaluates that the user "understands" the route guidance using the object.

[0059] Furthermore, the evaluation unit 104 evaluates the level of understanding based on the user evaluation information. When the evaluation unit 104 receives user evaluation information indicating that the user has understood the route guidance using the object based on the input information input to the input device 11, the evaluation unit 104 evaluates that the user has "understood" the route guidance using the object. When the evaluation unit 104 receives user evaluation information indicating that the user has not understood the route guidance using the object, the evaluation unit 104 evaluates that the user has "not understood" the route guidance using the object.

[0060] As described above, in this embodiment, the evaluation unit 104 evaluates whether the user has understood the route guidance using the object based on the evaluation indexes related to the user's behavior and / or state. The evaluation unit 104 may evaluate whether the user has understood based on one of the evaluation indexes, or may evaluate whether the user has understood based on each of multiple evaluation indexes. Furthermore, the evaluation unit 104 may use the evaluation indexes to calculate the understanding level expressed as a multi-level value of three or more levels.

[0061] Next, a control procedure of the route guidance method executed by the route guidance device 10 will be described with reference to FIG. 2. FIG. 2 is a flowchart showing an example of the control procedure for executing the route guidance method according to this embodiment. In this embodiment, when the vehicle 1 starts traveling along a travel route, the controller 12 starts the control flow from step S101. In step S101, the controller 12 acquires the current position of the vehicle 1 from the position acquisition device 2. In step S102, the controller 12 determines whether the vehicle 1 has approached a guidance point on the travel route based on the current position of the vehicle 1 and map information. If it is determined that the user has approached the guidance point, the controller 12 proceeds to step S103. If it is determined that the user has not approached the guidance point, the controller 12 returns to step S101 and repeats the subsequent flow.

[0062] In step S103, the controller 12 acquires basic guidance information from the database 5. The basic guidance information is information including the direction in which the user should travel at the guidance point. In step S104, the controller 12 acquires ambient environment information including objects around the user from the external vehicle sensor 3. In step S105, the controller 12 calculates the priority of the objects around the user. For example, the controller 12 recognizes the objects based on the ambient environment information and calculates an index value for calculating the priority of the recognized object. The controller 12 then calculates the priority of the object based on the calculated index value and an algorithm acquired from the database 5. In step S106, the controller 12 selects objects to be used for route guidance. The controller 12 compares the priority calculated for each object around the user with a predetermined priority threshold, and selects objects whose priority exceeds the predetermined priority threshold as objects to be used for route guidance.

[0063] In step S107, the controller 12 generates guidance information including route guidance using the selected object. The controller 12 generates guidance information including the basic guidance information acquired in step S103 and supplemental guidance information for specifying a guidance point using the object selected in step S106. For example, if the guidance point is an intersection and the selected object is a convenience store, the supplemental guidance information for specifying a guidance point using the object is text such as "This is an intersection where you can see a convenience store."

[0064] In step S108, the controller 12 outputs the guidance information generated in step S107 to provide route guidance to the user. For example, the controller 12 causes the output device 13 to output the guidance information as audio information. In step S109, the controller 12 acquires user information related to the user's behavior and / or state and traveling information of the vehicle 1 in which the user is riding. For example, the controller 12 acquires user behavior information, user biometric information, and user input information as the user information.

[0065] In step S110, the controller 12 evaluates the user's understanding of the route guidance output in step S108 based on the user information and / or the driving information of the vehicle 1. For example, the controller 12 evaluates that the user does not understand the route guidance if the user's body temperature or sweat rate is elevated based on biological information. The controller 12 also evaluates that the user does not understand the route guidance if the user does not drive correctly according to the route guidance based on driving accuracy information. The controller 12 also evaluates that the user does not understand the route guidance if user evaluation information indicating that the user does not understand the route guidance is input based on the user's input information. In step S111, the controller 12 transmits a control signal to the server 6 to control updating of the priority based on the evaluation result of the user's understanding in step S110. For example, the controller 12 updates the algorithm so as to lower the priority of the object used in the route guidance that the user evaluated in step S111 as not being understood by the user. The server 6 updates the priority of the object based on the received evaluation result of the user's understanding and stores it in the database 61.

[0066] Furthermore, the controller 12 may update the priority so that the higher the number of evaluation indexes that indicate that the user does not understand the route guidance, the lower the priority. Here, an example of a method for updating priorities based on evaluation indexes indicating whether or not the user understood the route guidance will be described with reference to FIG. 3. FIG. 3 is a flowchart illustrating an example of a control procedure for a priority updating method according to an embodiment of the present invention. In this embodiment, the controller 12 acquires user information and / or driving information in step S109 of FIG. 2, and then starts the control flow from step S201. In step S201, the controller 12 determines, based on the user information, whether or not the user hesitated when the vehicle 1 approached the guidance point. For example, the controller 12 determines that the user hesitated when the user's body temperature or sweat rate rose or when the vehicle 1 braked suddenly.

[0067] If it is determined that the user hesitated when the vehicle 1 approached the guidance point, the controller 12 proceeds to step S202. If it is determined that the user did not hesitate when the vehicle 1 approached the guidance point, the controller 12 proceeds to step S203. In step S202, the controller 12 corrects the priority of the object used in the route guidance so as to lower it. In step S203, the controller 12 determines whether the user has made a driving error in response to the route guidance. If the controller 12 acquires driving correctness information indicating that the user driving the vehicle 1 has not made a driving error in response to the route guidance, the controller 12 determines that the user has made a driving error in response to the route guidance. If it is determined that the user has made a driving error in response to the route guidance, the controller 12 proceeds to step S204. If it is determined that the user has not made a driving error in response to the route guidance, the controller 12 proceeds to step S205. In step S204, the controller 12 corrects the priority of the object used in the route guidance so as to lower it.

[0068] In step S205, the controller 12 determines whether the user has made an input indicating that the user does not understand the route guidance. When the controller 12 acquires user evaluation information indicating that the user does not understand the route guidance, the controller 12 determines that the user has made an input indicating that the user does not understand the route guidance. When the controller 12 determines that the user has made an input indicating that the user does not understand the route guidance, the controller 12 proceeds to step S206. When the controller 12 determines that the user has not made an input indicating that the user does not understand the route guidance, the controller 12 proceeds to step S207. In step S206, the controller 12 corrects the priority of the object used in the route guidance so that it is lowered. In step S207, the controller 12 updates the priority to the corrected priority. For example, the controller 12 adjusts each weight included in the algorithm for calculating the priority to the corrected priority.

[0069] 2, the controller 12 updates the algorithm for calculating the priority of an object each time the user passes a guidance point, but the present invention is not limited to this. For example, after determining the travel route of the vehicle 1, the controller 12 acquires an algorithm for calculating the priority of an object from the server 6 and stores the algorithm in the database 5 before the vehicle 1 starts traveling. Then, after the vehicle 1 finishes traveling, the controller 12 may transmit the evaluation result of the user's understanding to the server 6 and update the algorithm stored in the database 61. Furthermore, the controller 12 is not limited to determining the priority based on the priority each time the user approaches a guidance point during traveling, and may instead acquire the priority of objects around the user stored in the database 5.

[0070] In the above description, the level of understanding is expressed as a binary value of whether or not the user understood. However, this is not limiting and the level of understanding may be expressed as a multi-level value of three or more levels. For example, the level of understanding may be calculated in multiple levels according to the evaluation results of multiple evaluation indexes. The evaluation unit 104 calculates the level of understanding to be lower as the number of evaluation indexes indicating that the user does not understand the route guidance increases. The evaluation unit 104 calculates the level of understanding to be higher as the number of evaluation indexes indicating that the user does not understand the route guidance decreases. The level of understanding may also be the driving success probability that the user drives correctly according to the route guidance.

[0071] Furthermore, the priority calculation unit 102 may calculate the priority of the object by adding a term based on the evaluation result of the user's understanding level to the algorithm described in equation (1). For example, the priority calculation unit 102 calculates the priority based on the following equation (2).

number

[0072] As described above, in this embodiment, the controller calculates the priority of using an object for route guidance for objects around the user, selects an object to use for route guidance from among objects with a priority higher than a predetermined priority threshold, provides route guidance using the selected object, evaluates the user's understanding of the route guidance using the object, and updates the priority of the object according to the evaluation result of the understanding level. This makes it possible to improve the ease of understanding of route guidance tailored to the user.

[0073] In this embodiment, the controller acquires image information of a surrounding image including multiple objects, position information of the objects on a map, and / or position information of the user on the map, and calculates priorities based on at least one of the feature amounts of each of the multiple objects shown in the surrounding image, the feature amounts between the multiple objects shown in the surrounding image, the feature amounts of the positions of the objects on the map, and the feature amount of the user's position on the map. This allows objects suitable for route guidance to be selected based on the features of the objects around the user.

[0074] In this embodiment, the controller acquires user behavior information related to the user's behavior and calculates priorities based on the user behavior information. This allows objects suitable for route guidance to be selected based on the user's behavior. For example, objects suitable for route guidance can be selected based on the user's designation of an object they wish to use for route guidance or the user's line of sight while the vehicle is traveling.

[0075] Furthermore, in this embodiment, when the number of objects whose priorities exceed a predetermined priority threshold is greater than a predetermined object number threshold set in advance as the number of objects to be used for route guidance, the controller randomly selects, from among the objects whose priorities exceed the predetermined priority threshold, objects equal in number to the predetermined object number threshold as objects to be used for route guidance. This allows for randomness in the selection of objects to be used for route guidance, making it possible to provide route guidance using various objects and update priorities based on an evaluation of the user's level of understanding.

[0076] In addition, in this embodiment, the controller acquires driving accuracy information indicating whether the user driving the vehicle drove correctly in response to the route guidance, and evaluates the level of understanding based on the driving accuracy information. This allows the controller to increase the priority of the object used in the route guidance when the user drove correctly, and decrease the priority of the object used in the route guidance when the user drove incorrectly.

[0077] In this embodiment, the controller acquires driving information of the vehicle when the vehicle driven by the user approaches a guidance point that requires route guidance, and evaluates the understanding level based on the driving information. This allows the controller to evaluate the understandability of the route guidance and update the priority in accordance with the impact that the understandability of the route guidance has on the behavior of the vehicle.

[0078] In this embodiment, the controller acquires biometric information of the user when the user approaches a guidance point that requires route guidance, and evaluates the level of understanding based on the biometric information. This allows the controller to evaluate the ease of understanding of the route guidance and update the priority in accordance with the user's biometric response to the ease of understanding of the route guidance.

[0079] In this embodiment, the controller acquires user evaluation information, which includes the user's evaluation of the route guidance using the object, input by the user via the steering switch or voice input, and evaluates the comprehension level based on the user evaluation information. This allows the controller to evaluate the comprehension level of the route guidance and update the priority level in accordance with the user's direct evaluation of the comprehension level of the route guidance.

[0080] It should be noted that the above-described embodiments have been described to facilitate understanding of the present invention, and are not intended to limit the present invention. Therefore, each element disclosed in the above-described embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0081] Furthermore, for example, in the present embodiment, the algorithm for calculating the priority is described as an algorithm that integrates the evaluation results of the understanding levels of multiple users, i.e., common to multiple users. However, this is not limited to this, and the algorithm may be set for each user. In this case, the algorithm is adjusted, for example, by weighting, for each user according to the understanding level of each user. The adjusted algorithm may be stored in the database 5, not in the server 6. Furthermore, the priority calculation unit 102 may not update the priority for a guidance point where the user has repeatedly driven correctly following the route guidance. Furthermore, priority updating may be performed only for guidance points where users frequently make driving errors or where there are many users with low levels of understanding. [Explanation of symbols]

[0082] 100...Route guidance system 10...Route guidance device 11...Input device 12...Controller 101…Information acquisition department 102...Priority calculation unit 103...Route guidance section 104...Evaluation Department 13...Output device 14...Communication equipment 2...Position acquisition device 3...External sensor 4...In-vehicle sensor 5. Database 6...Server

Claims

1. A route guidance method executed by a controller to provide a user with route guidance to a destination, comprising: The controller calculating a priority of using an object around the user for the route guidance; selecting the object to be used for the route guidance from among the objects whose priorities are greater than a predetermined priority threshold; performing the route guidance using the selected object; acquiring travel information of the vehicle driven by the user when the vehicle approaches a guidance point requiring the route guidance and / or user information of the user; determining whether the user hesitated when approaching the guidance point based on the travel information and / or the user information; A route guidance method that updates the priority for the object depending on whether the user hesitates.

2. The controller acquiring image information of a surrounding image including a plurality of the objects, position information of the objects on a map, and / or position information of the user on the map; calculating the priority using at least one of a feature amount of each of the plurality of objects shown in the surrounding image, a feature amount between the plurality of objects shown in the surrounding image, a feature amount of a position of the object on the map, and a feature amount of a position of the user on the map as a quantitative index value; 2. The route guidance method of claim 1, wherein the index value is at least one of consistency, which indicates the time the object appears in the surrounding image; visibility, which indicates the size of the area the object occupies in the surrounding image; saliency, which indicates the likelihood of the object attracting attention; uniqueness, which indicates the degree of difference between the object and other objects around the object; proximity of the object to the guidance point; and proximity of the user to the guidance point.

3. The controller 3. The route guidance method according to claim 1, wherein, when the number of objects whose priority exceeds the predetermined priority threshold is greater than a predetermined object number threshold that is set in advance as the number of objects to be used for the route guidance, the same number of objects as the predetermined object number threshold are randomly selected from the objects whose priority exceeds the predetermined priority threshold as the objects to be used for the route guidance.

4. The controller Acquire driving correctness information indicating whether the user who drives the vehicle has driven correctly in response to the route guidance; correcting the priority of the object to be lowered when it is determined that the user has hesitated based on the travel information and / or the user information; When it is determined that the user has made a driving error in response to the route guidance based on the driving correctness information, the priority of the object is corrected to be lowered; The route guidance method according to claim 1 or 2, wherein the priority for the object is updated to the corrected priority for the object.

5. The controller acquiring biometric information of the user when the user approaches the guidance point; The route guidance method according to claim 1 or 2, wherein it is determined whether the user hesitated when approaching the guidance point based on the biological information.

6. The controller acquiring user evaluation information input by the user via a steering switch or voice input, the user evaluation information including an evaluation by the user of the route guidance using the object; correcting the priority of the object to be lowered when it is determined that the user has hesitated based on the travel information and / or the user information; correcting the priority of the object to be lowered when it is determined based on the user evaluation information that the user has input an indication that the user does not understand the route guidance; The route guidance method according to claim 1 or 2, wherein the priority for the object is updated to the corrected priority for the object.

7. A route guidance device including a controller that provides route guidance to a destination to a user, The controller calculating a priority of using an object in the route guidance for an object around the user; selecting the object to be used for the route guidance from among the objects whose priorities are greater than a predetermined priority threshold; performing the route guidance using the selected object; acquiring travel information of the vehicle driven by the user when the vehicle approaches a guidance point requiring the route guidance and / or user information of the user; determining whether the user hesitated when approaching the guidance point based on the travel information and / or the user information; A route guidance device that updates the priority for the object depending on whether the user hesitates or not.

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