JP2021156845A - Map information management system and map information management program - Google Patents

Abstract

To raise the possibility that the whole of peripheral map information of a travel route can be stored in a temporary storage unit.SOLUTION: A map information management system comprises: a delivery processing unit for exercising control so that the peripheral map information of a vehicle's travel route is delivered from a map server; and a map information management unit for exercising management so that the peripheral map information is stored in a temporary storage unit. When the peripheral map information of a second travel route whose data volume of peripheral map information is larger than a first travel route is stored in the temporary storage unit, the value of the data volume per unit area of peripheral map information that is stored in the temporary storage unit and/or the value of the widthwise size of area of the travel route is small as compared with the case where the peripheral map information of the first travel route is stored in the temporary storage unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to a map information management system and a map information management program.

Conventionally, there is known a guidance system that guides a vehicle by receiving map information from a map server. Such a map server stores a plurality of map information having different densities of end points of a road section for the same area. For example, a map server stores multiple map information with different levels of roughness, from the most detailed map information including narrow streets to the coarsest map information including only major roads such as highways and parts of national roads. There is. Patent Document 1 discloses a technique of referring to traffic information at the time of route search and displaying a detailed map of the vicinity of an event occurrence location when an event satisfying a predetermined condition occurs.

Japanese Unexamined Patent Publication No. 2005-114546

The guidance system that receives map information from the map server and provides route guidance receives map information along the vehicle's travel route from the departure point to the destination and temporarily stores it. However, the amount of map information data along the travel route may exceed the storage capacity of the temporary storage unit, such as when the travel route is long. In this case, there is a problem that the map information along the traveling route cannot be stored in the temporary storage unit.

The present invention has been made in view of the above problems, and an object of the present invention is to increase the possibility that the entire peripheral map information of a traveling route can be stored in a temporary storage unit.

In order to achieve the above object, the map information management system of the present invention stores the peripheral map information of the vehicle traveling route in the distribution processing unit that controls the distribution from the map server and the peripheral map information in the temporary storage unit. When the peripheral map information of the second travel route, which is provided with a map information management unit that manages the information so as to be managed and has a larger amount of peripheral map information data than the first travel route, is stored in the temporary storage unit. Compared with the case where the peripheral map information of the first traveling route is stored in the temporary storage unit, the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the width direction of the traveling route. At least one value of the area size is small.

Further, in order to achieve the above object, the map information management system of the present invention has a distribution processing unit that controls distribution of peripheral map information of the vehicle's travel route from a map server, and a temporary storage unit that stores the peripheral map information. When the peripheral map information of the data amount exceeding the capacity threshold of the temporary storage unit is stored in the temporary storage unit, the data amount does not exceed the capacity threshold. Compared to the case where the peripheral map information of the above is stored in the temporary storage unit, at least of the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the size of the area in the width direction of the traveling route. One value is small.

Further, in order to achieve the above object, the map information management program of the present invention is a distribution processing unit that controls a computer so that peripheral map information of a vehicle's travel route is distributed from a map server. It functions as a map information management unit that manages to be stored in the storage unit, and stores the peripheral map information of the second travel route, which has a larger amount of peripheral map information data than the first travel route, in the temporary storage unit. When this is done, the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the traveling are as compared with the case where the peripheral map information of the first traveling route is stored in the temporary storage unit. At least one value of the size of the region in the width direction of the route is small.

Further, in order to achieve the above object, the map information management program of the present invention is a distribution processing unit that controls a computer so that peripheral map information of a vehicle's travel route is distributed from a map server. When it functions as a map information management unit that manages to be stored in the storage unit and the peripheral map information of the amount of data exceeding the capacity threshold of the temporary storage unit is stored in the temporary storage unit, the capacity threshold is not exceeded. Compared to the case where the peripheral map information of the data amount is stored in the temporary storage unit, the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the size of the area in the width direction of the traveling route At least one of them is small.

In the map information management system and the map information management program, when the peripheral map information of the second travel route, which has a larger amount of data of the peripheral map information than the first travel route, is stored in the temporary storage unit, the first 1 At least one of the amount of data per unit area of the map and the size of the area in the width direction of the travel route is smaller than the case where the map information around the travel route is stored in the temporary storage unit. Further, when compared with the capacity threshold value of the temporary storage unit, when the peripheral map information of the data amount exceeding the capacity threshold value is stored in the temporary storage unit, the peripheral map information of the data amount not exceeding the capacity threshold value is temporarily stored. The value of at least one of the amount of data per unit area and the area size in the width direction of the traveling route is smaller than that in the case of being stored in the unit. Therefore, it is possible to increase the possibility that the entire peripheral map information of the traveling route can be stored in the temporary storage unit.

A block diagram showing the configuration of a map information management system and a map server. The figure which shows the data structure example of the map information. The flowchart which shows the map information management process of 1st Embodiment. The flowchart which shows the map information management process of 2nd Embodiment.

Here, embodiments of the present invention will be described in the following order.
(1) Overall configuration of the first embodiment:
(2) Map information management process of the first embodiment:
(3) Second embodiment:
(4) Other embodiments:

(1) Overall configuration of the first embodiment:
FIG. 1 is a block diagram showing the configurations of the map information management system 10 and the map server 20. The map server 20 stores a plurality of levels of map information having different densities of end points of road sections included in a unit area. The map server 20 includes a communication unit 21, a control unit 22 including a CPU, RAM, ROM, and the like, and a recording medium 23. The communication unit 21 is a device for wirelessly communicating with an external device, and the control unit 22 can communicate with the map information management system 10 via the communication unit 21. The control unit 22 can execute various programs stored in the recording medium 23 or the ROM. The control unit 22 of the present embodiment can execute the distribution program 220 as one of the programs.

The recording medium 23 stores the map information 231. The map information 231 includes node data indicating the positions of nodes corresponding to the end points of the road section, shape interpolation point data indicating the positions of shape interpolation points for specifying the shape of the road between the nodes, and links connecting the nodes. Contains link data and the like indicating. Here, the node corresponds to the intersection, and the link corresponds to the road section from the intersection to the intersection. The map information 231 is used for specifying the position of the vehicle, searching for a route to the destination, guiding the route, and the like. In the present embodiment, the link data includes information indicating the direction in which the vehicle can travel on the road section indicated by the link data. In addition, the link data includes information indicating the structure of the lane existing on the road. The lane structure indicates the number of lanes in which the vehicle can travel in each direction of travel. When the number of lanes changes in a part of the road section (for example, the part immediately before entering the intersection), information indicating the changing position and the number of lanes before and after the change is defined.

Further, the map information 231 includes a plurality of levels of map information in which the end points of the road sections included in the unit area, that is, the densities of the nodes are different. FIG. 2 is a diagram showing an example of data configuration of map information 231. The map information 231 includes six different levels of map information for the same area, such as levels 0, 2, 4, 6, and 10. The higher the level, the coarser the map, and the lower the level, the more detailed the map. The level 0 map information includes all information including the lane structure, etc., and the map information management system 10 is level 0 when guiding a non-straight direction as a traveling direction at an intersection or the like. Use map information. On the other hand, for example, level 4 map information includes only highways and major national roads. For example, route search can theoretically be processed simply by referring to level 0 map information, but by using higher level map information such as level 4, the amount of calculation related to route search is reduced. can do. In this way, in the map information management system 10, map information at a level corresponding to the processing content is referred to.

The distribution program 220 executed by the control unit 22 includes a distribution unit 221. The distribution unit 221 is a program module that causes the control unit 22 to execute a function of distributing map information to the map information management system 10. The control unit 22 receives a map information transmission request from the map information management system 10 by the function of the distribution unit 221. The transmission request indicates the area of the map to be transmitted and the level. The control unit 22 specifies the area and level to be transmitted according to the transmission request by the function of the distribution unit 221 and distributes (transmits) the map information of the specified area and level to the map information management system 10.

The map information management system 10 is mounted on the vehicle and acquires map information from the map server 20. The map information management system 10 includes a communication unit 11, a control unit 12 including a CPU, RAM, ROM, and the like, a recording medium 13, and a user I / F unit 14. The communication unit 11 is a device for wirelessly communicating with an external device, and the control unit 12 can communicate with the map server 20 via the communication unit 11. The user I / F unit 14 is an interface unit for inputting a user's instruction and providing various information to the user, and includes a touch panel type display, a switch, a speaker, and the like (not shown). That is, the user I / F unit 14 includes an image / audio output unit and a user-instructed input unit.

The control unit 12 can execute various programs stored in the recording medium 13 or the ROM. The control unit 12 of the present embodiment can execute the map information management program 121 as one of the programs. The control unit 12 manages the map information in the guidance of the traveling route by the processing of the map information management program 121. The control unit 12 also includes a temporary storage unit 123 that temporarily stores the map information received from the map server 20.

The vehicle is further equipped with a GNSS receiving unit 15, a vehicle speed sensor 16, and a gyro sensor 17. The GNSS receiving unit 15 is a device that receives signals from the Global Navigation Satellite System. The GNSS receiving unit 15 receives radio waves from the navigation satellite and outputs a signal for calculating the position of the vehicle via an interface (not shown). The control unit 12 acquires this signal to acquire the position of the vehicle. The vehicle speed sensor 16 outputs a signal corresponding to the rotation speed of the wheels provided in the vehicle. The control unit 12 acquires this signal via an interface (not shown) to acquire the vehicle speed.

The gyro sensor 17 detects the angular acceleration for turning in the horizontal plane of the vehicle and outputs a signal corresponding to the direction of the vehicle. The control unit 12 acquires this signal to acquire the traveling direction of the vehicle. The vehicle speed sensor 16, the gyro sensor 17, and the like are used to identify the traveling track of the vehicle. In the present embodiment, the control unit 12 specifies the position of the vehicle based on the starting point and the traveling track of the vehicle, and the position of the vehicle specified based on the starting point and the traveling track is determined by the GNSS receiving unit 15. Correct based on the output signal.

The map information management program 121 executed by the control unit 12 of the map information management system 10 includes a search function unit 122a, a route guidance function unit 122b, and a route guidance function unit 122b in order to manage the map information used for guiding the travel route of the vehicle. It includes a map drawing function unit 122c, a matching function unit 122d, a distribution processing unit 122e, and a map information management unit 122f.

The search function unit 122a is a program module that enables the control unit 12 to realize a function of searching a travel route from the current location to the destination when the destination is set according to the user operation. Specifically, when the destination is set according to the user operation, the control unit 12 sends a route search request including the current location and the destination of the vehicle specified by the GNSS receiving unit 15 and the like to the communication unit 11. It is transmitted to the map server 20 via. When the map server 20 receives the route search request, the map server 20 creates one or a plurality of travel routes according to the route search request, and transmits this to the map information management system 10. The control unit 12 receives the travel route via the communication unit 11 and the distribution processing unit 122e, and controls to display the travel path on the display. In this way, the travel route is received from the map server 20. Here, the traveling route is an array of nodes connecting the starting point to the destination.

When the travel route is set, the control unit 12 generates an acquisition request for requesting peripheral map information by the function of the search function unit 122a. Here, the peripheral map information is map information including a traveling route from a starting point to a destination and having a length in the width direction of the traveling route within the range of the first reference width. Here, the first reference width is a preset length. The peripheral map information acquisition request includes identification information that identifies the search function unit 122a as the request source of the acquisition request, and information indicating the range of the peripheral map information. Further, this acquisition request is information requesting acquisition of peripheral map information of all levels. The surrounding map information is acquired from the map server 20 via the communication unit 11 by the function of the distribution processing unit 122e under the management by the function of the map information management unit 122f. The surrounding map information transmitted from the map server 20 is stored in the temporary storage unit 123.

The travel route is selected by the user operation, and the travel route is set when the guidance start button displayed on the display is selected. Further, when the vehicle starts traveling while a plurality of traveling routes are presented, the traveling route set as the recommended traveling route among the plurality of traveling routes is set as the traveling route to be used. ..

Further, the control unit 12 is used in the route guidance based on the current location of the vehicle and the travel route set as the guide route in the map information management system 10 each time the route is guided by the first distance. Specify the acquisition target area for which the map information is to be acquired. Then, the control unit 12 generates an acquisition request for requesting the map information of the acquisition target area from the map information management unit 122f by the function of the search function unit 122a. Here, the first distance is a predetermined distance. Further, the acquisition target area is an area from the current location of the vehicle to a certain distance along the traveling path and to a certain distance along the width direction of the traveling path. Further, this acquisition request is information requesting map information of level 0 to level 4. In this way, by acquiring the map information based on the current location after the vehicle has moved, the map information can be used for re-search.

The route guidance function unit 122b is a program module that allows the control unit 12 to realize a function of providing route guidance along the traveling route of the vehicle. Specifically, the control unit 12 guides the traveling direction at an intersection or an entrance / exit of an expressway where the vehicle should travel in a non-straight direction. The control unit 12 refers not only to the traveling route but also to the map information in the route guidance. Therefore, in order to acquire the map information, the control unit 12 specifies the acquisition target area based on the travel route each time the route guidance function unit 122b moves a second distance. Then, the control unit 12 generates an acquisition request for requesting the map information of the acquisition target area from the map information management unit 122f by the function of the route guidance function unit 122b. Here, the second distance is a predetermined distance. The second distance shall be longer than the first distance. However, the second distance may be equal to the first distance or shorter than the first distance. The acquisition target area is an area from the current location of the vehicle to a certain distance along the traveling route. The acquisition target area specified by the function of the route guidance function unit 122b is shorter in the width direction of the traveling route than the acquisition target area specified by the search function unit 122a. The length of the acquisition target area in the traveling direction may be equal to or different from the target area specified by the search function unit 122a.

The acquisition request generated by the function of the route guidance function unit 122b includes identification information for identifying the route guidance function unit 122b as a generation source of the acquisition request and information indicating an acquisition target area. The acquisition request generated by the function of the route guidance function unit 122b is information that requests map information of the area specified by the function of the route guidance function unit 122b based on the traveling route. When the acquisition request is generated, the map information related to the acquisition request is stored in the temporary storage unit 123 by the function of the map information management unit 122f. The control unit 12 provides route guidance using the map information stored in the temporary storage unit 123. In the route guidance, it is sufficient that the map information of the most detailed level is available, and the map information of other levels is not referred to. The control unit 12 of the present embodiment provides route guidance by referring to the map information of level 0 by the function of the route guidance function unit 122b.

The map drawing function unit 122c is a program module that enables the control unit 12 to realize a function of drawing a map. When the traveling route is set, the control unit 12 draws a map including the starting point to the destination of the traveling route by the function of the map drawing function unit 122c and displays it on the display. In this case, the control unit 12 specifies a display scale capable of displaying the traveling route from the departure point to the destination based on the distance from the departure point to the destination by the function of the map drawing function unit 122c. Here, the display scale that can display the travel route from the departure point to the destination is the narrowest range of the display scales that can display the entire travel route on the display. As another example, in the display scale capable of displaying the travel route from the departure point to the destination, the ratio of the smallest rectangular area including the entire travel route to the entire display to the entire display is a predetermined ratio. The scale may be as follows.

The control unit 12 refers to the map information in order to draw a map including the traveling route from the starting point to the destination at the display scale by the function of the map drawing function unit 122c. Therefore, the control unit 12 generates an acquisition request for requesting the map information of the acquisition target area from the map information management unit 122f by the function of the map drawing function unit 122c. Here, the acquisition target area is an area including the entire traveling route determined according to the display scale. The acquisition request includes identification information of the map drawing function unit 122c as a transmission source of the acquisition request, information indicating an acquisition target area, and a display scale capable of displaying from the departure point to the destination. In response to the acquisition request, the control unit 12 draws a map of the traveling route by using the map information stored in the temporary storage unit 123 by the function of the map information management unit 122f.

The control unit 12 also draws a map including the current location of the vehicle during route guidance and displays it on the display. In this case, the control unit 12 displays the map at a preset display scale. The control unit 12 refers to the map information in order to draw the map. Therefore, the control unit 12 uses the function of the map drawing function unit 122c to guide the route, and each time the control unit 12 moves the third distance, the area displayed on the display from the current location of the vehicle and the display scale based on the travel route. Is specified as the acquisition target area. Then, the control unit 12 generates an acquisition request for requesting the map information of the acquisition target area from the map information management unit 122f by the function of the map drawing function unit 122c. Here, the third distance may be equal to or different from at least one of the first distance and the second distance.

The acquisition request generated by the function of the map drawing function unit 122c includes identification information for identifying the map drawing function unit 122c as the generation source of the acquisition request, information indicating the acquisition target area, and a predetermined display. Scale is included. The display scale can be changed according to the user operation, and when the display scale is changed according to the user operation, the map is drawn at the changed display scale, and the acquisition request related to the changed display scale is performed. Is generated. The acquisition request generated by the function of the map drawing function unit 122c is information requesting map information of the area specified by the function of the map drawing function unit 122c based on the traveling route. In response to the acquisition request, the control unit 12 draws a map including the current location of the vehicle by using the map information stored in the temporary storage unit 123 by the function of the map information management unit 122f. The control unit 12 draws a map by referring to the map information of the level according to the display scale by the function of the map drawing function unit 122c.

The matching function unit 122d is a program module that causes the control unit 12 to realize a function of specifying which road the current location of the vehicle is on by referring to the map information. The control unit 12 periodically executes a matching process for identifying the position of the vehicle on the road during route guidance. In order to perform matching during route guidance, the control unit 12 uses the function of the matching function unit 122d to move forward in the traveling direction from the current location of the vehicle along the traveling route each time the control unit 12 travels the fourth distance. The area up to a certain distance is specified as the acquisition target area. Then, the control unit 12 generates an acquisition request for requesting the map information of the acquisition target area from the map management unit 22f by the function of the matching function unit 122d. Here, the fourth distance may be equal to or different from at least one of the first distance, the second distance, and the third distance.

In order to acquire the map information, the control unit 12 generates a request for acquiring the map information of the acquisition target area to the map information management unit 122f by the function of the matching function unit 122d. The acquisition request generated by the matching function unit 122d includes identification information for identifying the matching function unit 122d as a generation source and information indicating an acquisition target area. The acquisition request generated by the function of the matching function unit 122d is information that requests map information of the area specified by the function of the matching function unit 122d based on the traveling route. The control unit 12 draws a map including the current location of the vehicle by using the map information stored in the temporary storage unit 123 by the function of the map information management unit 122f in response to the acquisition request. The control unit 12 performs matching by referring to the map information of level 0 by the function of the matching function unit 122d.

The distribution processing unit 122e is a program module that allows the control unit 12 to realize a function of controlling the map server 20 to distribute information such as map information and a vehicle's travel route via the communication unit 11. The control unit 12 controls, for example, to distribute the map information around the traveling route of the vehicle from the map server 20 by the function of the distribution processing unit 122e. Specifically, the control unit 12 transmits a transmission request for map information to be distributed to the map server 20 by the function of the distribution processing unit 122e. On the other hand, the map server 20 distributes the map information to the map information management system 10 in response to the transmission request. The control unit 12 receives the map information as a response to the transmission request.

The map information management unit 122f is a program module that enables the control unit 12 to acquire a function of acquiring map information from the map server 20 via the distribution processing unit 122e and the communication unit 11 and storing the map information in the temporary storage unit 123. The control unit 12 performs the following processing by the function of the map information management unit 122f. The control unit 12 receives an acquisition request from the search function unit 122a, the route guidance function unit 122b, the map drawing function unit 122c, and the matching function unit 122d from the map server 20 via the distribution processing unit 122e and the communication unit 11. Manage to get map information.

The map information of the area and level related to the acquisition request generated by one function may already be stored in the temporary storage unit 123 in response to the acquisition request generated by the other function. Therefore, when the control unit 12 receives the acquisition request, it first determines whether or not the map information of the area and level related to the acquisition request is stored in the temporary storage unit 123. Then, the control unit 12 controls to receive the map information from the map server 20 as described above when the map information of the area and the level related to the acquisition request is not stored in the temporary storage unit 123. If some of the map information of the acquisition area and level related to the acquisition request is not stored in the temporary storage unit 123, the control unit 12 uses the temporary storage unit 123 of the map information related to the acquisition request. It suffices to generate a transmission request for some map information that is not stored in.

As described above, the control unit 12 generates a request for acquiring peripheral map information when the travel route is set by the function of the search function unit 122a. In this case, the control unit 12 controls to acquire the peripheral map information related to the acquisition request by the function of the map information management unit 122f and store it in the temporary storage unit 123. However, the amount of data of the peripheral map information is large, and it may not be possible to store all of the peripheral map information related to the acquisition request in the temporary storage unit 123. Therefore, the control unit 12 of the present embodiment performs a process of appropriately reducing the amount of data of the surrounding map information by the function of the map information management unit 122f. Hereinafter, the process of appropriately deleting the data amount of the peripheral map information will be described.

The control unit 12 first estimates the amount of data of the surrounding map information. Specifically, the control unit 12 obtains the first estimated value of the data amount of the peripheral map information based on the length of the traveling route. The control unit 12 calculates the first estimated value of the data amount of the surrounding map information by multiplying the distance from the departure point to the destination of the traveling route by the first unit data amount. Here, the first unit data amount is a reference value of the data amount per unit distance in the traveling direction of the traveling route. The unit distance is a preset value. Further, the first unit data amount is a value assuming that the length in the width direction of the traveling route is the first reference width, and is a value when all levels of map information are included. It is assumed that the first unit data amount is set in advance. The first unit data amount may be, for example, the average value of the data amount of the map information of all levels with respect to the area determined by the unit distance and the first reference width of the map information.

In order to specify the correct amount of data in the surrounding map information, it is necessary to refer to the surrounding map information of the actual driving route. On the other hand, in the map information management system 10 of the present embodiment, a first estimated value depending on the length of the traveling route is obtained instead of the amount of data of the surrounding map information, and based on the first estimated value, the first estimated value is obtained. Evaluate the amount of data in the surrounding map information.

The control unit 12 further compares the first estimated value with the capacitance threshold. Here, the capacity threshold value is a reference value for determining whether or not all the peripheral map information can be stored in the temporary storage unit 123. That is, the capacity threshold value is a value determined according to the capacity of the temporary storage unit 123. It is assumed that the capacity threshold is set in advance. When the first estimated value does not exceed the capacity threshold value, the control unit 12 acquires all levels of map information stored in the map server 20 from the map server 20 via the communication unit 11 and the distribution processing unit 122e. , Control to store this in the temporary storage unit 123.

On the other hand, when the first estimated value exceeds the capacity threshold value, the control unit 12 limits the level of the peripheral map information stored in the temporary storage unit 123 to a number smaller than all levels. Specifically, the control unit 12 is a target candidate for storing the lower level peripheral map information in the temporary storage unit 123 among the peripheral map information of all levels. Here, the lower levels are a predetermined number of levels from the lowest level (the most detailed level). In this embodiment, the lower levels are three levels (level 0, level 2 and level 4) from the restart level. Then, the control unit 12 obtains an estimated value of the amount of data of the peripheral map information when the level is limited, that is, the peripheral map information of the level 0 to the level 4, as the second estimated value. Specifically, the control unit 12 multiplies the distance of the surrounding map information by the second unit data amount. Here, the second unit data amount is a reference value of the data amount of the map information of levels 0 to 4 in the range determined by the unit distance in the traveling direction of the traveling route and the first reference width. The second unit data amount is a preset value. The second unit data amount may be, for example, the average value of the data amount of the map information of levels 0 to 4 with respect to the area determined by the unit distance and the first reference width of the map information. The second unit data amount is a value smaller than the first unit data amount.

The control unit 12 compares the second estimated value with the capacity threshold value. When the second estimated value does not exceed the capacity threshold value, the control unit 12 transfers the peripheral map information of levels 0 to 4 among the map information stored in the map server 20 to the communication unit 11 and the distribution processing unit. Obtained from the map server 20 via 122e. Then, the control unit 12 controls to store this in the temporary storage unit 123. By limiting the level in this way, it is possible to store the peripheral map information of the entire traveling route in the temporary storage unit 123. Further, since the control unit 12 can acquire the map information of the lower level even when the level is restricted, the control unit 12 acquires the map information necessary for the vehicle while traveling on the traveling route, such as route guidance and map drawing. can do.

When the second estimated value exceeds the capacity threshold value, the control unit 12 reduces the map range of the peripheral map information stored in the temporary storage unit 123. Specifically, the control unit 12 changes the length of the peripheral map information in the width direction of the traveling route from the first reference width to the second reference width. Here, the second reference width is a value shorter than the first reference width and is a preset length.

Then, the control unit 12 obtains an estimated value of the amount of data of the peripheral map information determined by the second reference width as the third estimated value. Specifically, the control unit 12 multiplies the distance of the traveling path by the third unit data amount. Here, the third unit data amount is a reference value of the data amount of the map information of levels 0 to 4 in the range determined by the unit distance in the traveling direction of the traveling route and the second reference width. The third unit data amount is a preset value. The third unit data amount may be, for example, the average value of the data amount of the map information of levels 0 to 4 with respect to the area determined by the unit distance and the second reference width of the map information. The third unit data amount is a value smaller than the second unit data amount.

The control unit 12 compares the third estimated value with the capacity threshold value. When the third estimated value does not exceed the capacity threshold value, the control unit 12 narrows the length of the peripheral map information in the width direction of the traveling route from the first reference width to the second reference width. Then, the control unit 12 acquires the peripheral map information of the level 0 to the level 4 in the area determined by the second reference width from the map server 20 via the communication unit 11 and the distribution processing unit 122e, and obtains this from the map server 20. Control to store in 123. By reducing the size of the region in the width direction of the travel route in this way, the peripheral map information of the entire travel route can be stored in the temporary storage unit 123.

When the third estimated value exceeds the capacity threshold value, the control unit 12 sets the range of a certain distance from the departure point side along the traveling direction of the traveling route as the receiving unit, and sets the level 0 to 0 of the receiving unit. The level 4 peripheral map information, that is, a part of the peripheral map information is stored in the temporary storage unit 123. Here, the length in the width direction of the travel route of the map included in the peripheral map information of the reception unit is defined as the second reference width. Then, if the amount of data in the temporary storage unit 123 after storage is equal to or greater than the capacity threshold value, the control unit 12 temporarily stores the peripheral map information of the next reception unit from level 0 to level 4 along the traveling direction. Store in. The control unit 12 repeats this process until the amount of data in the temporary storage unit 123 exceeds the capacity threshold value.

In this way, the control unit 12 obtains the first estimated value of the data amount of the peripheral map information based on the length of the traveling route, and the data amount of the peripheral map information sets the capacity threshold value based on the first estimated value. Determine if it exceeds. Then, when the first estimated value exceeds the capacity threshold value, the control unit 12 can reduce the amount of data per unit area of the peripheral map information by limiting the level of the peripheral map information. As a result, when the peripheral map information whose first estimated value exceeds the capacity threshold is stored in the temporary storage unit 123, when the peripheral map information whose first estimated value does not exceed the capacity threshold is stored in the temporary storage unit 123. The number of levels of peripheral map information stored in the temporary storage unit 123 is smaller than that of the above. Further, when limiting the level, the control unit 12 limits the level from a lower level, that is, the lowest level to a predetermined number of levels. As a result, it is possible to obtain necessary map information while traveling along the traveling route, such as route guidance and map drawing, while reducing the amount of data.

Further, each estimated value of the peripheral map information is a value corresponding to the amount of data of the peripheral map information. Since the number of levels is limited according to the estimated value, the number of levels is likely to be limited when the peripheral map information of the amount of data exceeding the capacity threshold is stored in the temporary storage unit 123. Therefore, when the peripheral map information of the data amount exceeding the capacity threshold is stored in the temporary storage unit 123, it is temporarily stored as compared with the case where the peripheral map information of the data amount not exceeding the capacity threshold is stored in the temporary storage unit 123. The number of levels of peripheral map information stored in the section is reduced.

Further, consider a case where the peripheral map information related to the first traveling route and the second traveling route longer than the first traveling route is stored in the temporary storage unit 123. In this case, when the peripheral map information of the second traveling route is stored in the temporary storage unit 123, the temporary storage unit is compared with the case where the peripheral map information of the first traveling route is stored in the temporary storage unit 123. The number of levels of peripheral map information stored in is reduced.

As described above, the map information management system 10 of the present embodiment sets the data amount of the peripheral map information of the traveling route as an approximate value before receiving the peripheral map information from the map server 20 according to the distance of the traveling route. Find the first estimate. Then, the map information management system 10 determines whether or not the peripheral map information can be stored in the temporary storage unit 123 based on the first estimated value. Then, when the map information management system 10 determines that the peripheral map information cannot be stored in the temporary storage unit 123, the map information management system 10 limits the level of the peripheral map information, and further, the width direction of the traveling route of the peripheral map information. Reduce the size of the area. By reducing the amount of data of the peripheral map information in this way, the possibility of storing the peripheral map information in the temporary storage unit can be increased.

Further, from the third estimated value in which the level and size are restricted, it may be determined that all the peripheral map information cannot be stored in the temporary storage unit 123 even if the level and size are restricted. In this case, the map information management system 10 sequentially stores the peripheral map information of the reception unit along the travel route from the departure point side in the reception unit until the amount of data in the temporary storage unit 123 reaches the capacity threshold value. go. As a result, the surrounding map information can be stored as much as the amount of data that can be stored.

(2) Map information management process of the first embodiment:
Next, the map information management process executed by the function of the map information management program 121 will be described. FIG. 3 is a flowchart showing the map information management process. The map information management process is a process realized by the control unit 12 by the function of the map information management unit 122f. The map information management process is executed when the travel route is set. The control unit 12 calculates the first estimated value of the surrounding map information based on the distance of the traveling route and the amount of the first unit data (step S100). Next, the control unit 12 compares the first estimated value with the capacity threshold value (step S105). When the first estimated value does not exceed the capacity threshold value (N in step S105), the control unit 12 acquires peripheral map information from the map server 20 via the distribution processing unit 122e and the communication unit 11, and temporarily uses this. It is controlled to be stored in the storage unit 123 (step S110). This completes the map information management process. The peripheral map information stored in the temporary storage unit 123 in step S110 is the map information of the area where the length in the width direction of the traveling route is the first reference width, and the map of all levels stored in the map server 20. Information.

On the other hand, in step S105, when the first estimated value exceeds the capacity threshold value (Y in step S105), the control unit 12 limits the level of the surrounding map information to a lower level and calculates the second estimated value (Y in step S105). Step S115). Next, the control unit 12 compares the second estimated value with the capacity threshold value (step S120). When the second estimated value does not exceed the capacity threshold value (N in step S120), the control unit 12 receives the level-limited peripheral map information from the map server 20 via the distribution processing unit 122e and the communication unit 11. It is controlled to acquire and store it in the temporary storage unit 123 (step S125). This completes the map information management process. The peripheral map information stored in the temporary storage unit 123 in step S125 is the map information of the area where the length in the width direction of the traveling route is the first reference width, and is the map information of levels 0 to 4.

In step S120, when the second estimated value exceeds the capacity threshold value (Y in step S120), the control unit 12 sets the length in the width direction of the traveling route corresponding to the peripheral map information from the first reference width to the second. The third estimated value is calculated by narrowing the reference width (step S130). Next, the control unit 12 compares the third estimated value with the capacity threshold value (step S135). When the third estimated value does not exceed the capacity threshold value (N in step S135), the control unit 12 receives the level and the range in the width direction of the travel route from the map server 20 via the distribution processing unit 122e and the communication unit 11. Acquires restricted peripheral map information and controls to store it in the temporary storage unit 123 (step S140). This completes the map information management process. The peripheral map information stored in the temporary storage unit 123 in step S140 is the map information of the area where the length in the width direction of the traveling route is the second reference width, and is the map information of levels 0 to 4.

In step S135, when the third estimated value exceeds the capacity threshold value (Y in step S135), the control unit 12 distributes the peripheral map information of the reception unit in order from the current location side along the travel route 122e. It is received from the map server 20 via the communication unit 11 and stored in the temporary storage unit 123 (step S145). The length of the peripheral map information of the reception unit in the width direction of the traveling route is the second reference width, and the level of the map information is level 0 to level 4. Next, the control unit 12 compares the amount of data stored in the temporary storage unit 123 with the capacity threshold value (step S150). When the amount of peripheral map information stored in the temporary storage unit 123 exceeds the capacity threshold value (Y in step S150), the map information management process is terminated.

When the amount of peripheral map information stored in the temporary storage unit 123 does not exceed the capacity threshold value (N in step S150), the control unit 12 stores the peripheral map information up to the destination in the temporary storage unit 123. It is determined whether or not it is (step S155). Even when the third estimated value exceeds the capacity threshold value, if the actual amount of peripheral map information data is smaller than the third estimated value, the peripheral map information to the destination is temporarily stored in the temporary storage unit 123. Can be stored in.

When the surrounding map information up to the destination is stored in the temporary storage unit 123 (Y in step S155), the control unit 12 ends the map information management process. If the surrounding map information to the destination is not stored in the temporary storage unit 123 (N in step S155), the control unit 12 advances the process to step S145. That is, the control unit 12 repeats the process of acquiring the peripheral map information of the reception unit that is not stored in the temporary storage unit 123.

(3) Second embodiment:
Next, the map information management system 10 and the map server 20 of the second embodiment will be mainly described as being different from the map information management system 10 and the map server 20 of the first embodiment. The configuration of the map information management system 10 and the map server 20 of the second embodiment is the same as that of the map information management system 10 and the map server 20 of the first embodiment.

However, the control unit 12 of the second embodiment receives a part of the peripheral map information in order from the starting point of the traveling route to the destination by the function of the distribution processing unit 122e. As a result, the peripheral map information is partially stored in the temporary storage unit 123. Specifically, the control unit 12 divides the travel route into partial routes of a certain distance from the current location along the departure location with the map information around the travel route. Then, the control unit 12 receives the peripheral map information of all levels corresponding to the partial route as the receiving unit, and sequentially receives the peripheral map information of the receiving unit as a part of the information.

Then, when the data amount of the peripheral map information stored in the temporary storage unit 123 exceeds the capacity threshold before all the peripheral map information is stored in the temporary storage unit 123, the control unit 12 is the temporary storage unit. Of the peripheral map information stored in 123, information at a predetermined level is deleted. As a result, the free space of the temporary storage unit 123 can be secured, and the storage of the peripheral map information can be continued. If the amount of data exceeds the capacity threshold even after limiting the level, the control unit 12 further, among the peripheral map information stored in the temporary storage unit 123, is the second reference in the width direction of the traveling route. Delete the information of the area larger than the width. As a result, the free space of the temporary storage unit 123 can be secured again, and the storage of the peripheral map information can be continued.

As described above, also in the second embodiment, when the peripheral map information of the data amount exceeding the capacity threshold is stored in the temporary storage unit 123, the peripheral map information of the data amount not exceeding the capacity threshold is stored in the temporary storage unit 123. The number of levels of peripheral map information stored in the temporary storage unit is smaller than when it is stored.

Further, consider a case where the peripheral map information related to the first traveling route and the second traveling route longer than the first traveling route is stored in the temporary storage unit 123. In this case, while the upper level peripheral map information of the second traveling route is deleted, the upper level peripheral map information of the first traveling route is stored without being deleted. Therefore, when the peripheral map information of the second traveling route is stored in the temporary storage unit 123, the temporary storage unit is compared with the case where the peripheral map information of the first traveling route is stored in the temporary storage unit 123. The number of levels of peripheral map information stored in is reduced. The upper levels are a predetermined number of levels from the widest level, and in the present embodiment, they are level 10, level 8, and level 6.

As described above, in the map information management system 10 according to the second embodiment, the peripheral map information is actually sequentially stored in the temporary storage unit 123 for each reception unit, and when the capacity threshold of the temporary storage unit 123 is exceeded, Delete the surrounding map information that has already been stored. As a result, it is possible to store the peripheral map information of the subsequent reception unit.

FIG. 4 is a flowchart showing the map information management process by the map information management system 10 according to the second embodiment. The map information management process is a process realized by the control unit 12 by the function of the map information management unit 122f. The control unit 12 divides the travel route into partial routes of a certain distance from the current location along the departure location with the map information around the travel route. Then, the control unit 12 uses the peripheral map information corresponding to the partial route as the reception unit, acquires the peripheral map information of all levels of the reception unit from the map server 20 via the distribution processing unit 122e and the communication unit 11, and temporarily stores the peripheral map information. It is controlled to be stored in the unit 123 (step S200).

Next, the control unit 12 compares the amount of data stored in the temporary storage unit 123 with the capacity threshold value. When the amount of data does not exceed the capacity threshold value (N in step S205), the control unit 12 determines whether or not all the peripheral map information up to the destination is stored in the temporary storage unit 123. When all the surrounding map information up to the destination is stored in the temporary storage unit 123 (Y in step S210), the control unit 12 ends the map information management process.

If the peripheral map information that is not stored in the temporary storage unit 123 remains (N in step S210), the control unit 12 advances the process to step S200. As a result, the storage of the peripheral map information in the temporary storage unit 123 is repeated.

On the other hand, in step S205, when the amount of data exceeds the capacity threshold value (Y in step S205), the control unit 12 has higher-level peripheral map information among the peripheral map information stored in the temporary storage unit 123. Is deleted (step S215). Specifically, the control unit 12 deletes the peripheral map information of the level 6 or higher level from the temporary storage unit 123 as the peripheral map information of the upper level. As a result, the free space of the temporary storage unit 123 can be increased.

Next, the control unit 12 compares the amount of data in the temporary storage unit 123 with the capacity threshold value. When the amount of data does not exceed the capacity threshold (N in step S220), the control unit 12 distributes the peripheral map information of the lower level, that is, the level 0 to the level 4, among the peripheral map information of the reception unit, to the distribution processing unit 122e. And it is controlled to be acquired from the map server 20 via the communication unit 11 and stored in the temporary storage unit 123 (step S225). Next, the control unit 12 determines whether or not all the peripheral map information up to the destination, which is level 0 to level 4 up to the destination, is stored in the temporary storage unit 123 (step S230). When all the surrounding map information up to the destination is stored in the temporary storage unit 123 (Y in step S230), the control unit 12 ends the map information management process. If the peripheral map information that is not stored in the temporary storage unit 123 remains (N in step S230), the process proceeds to step S220. As a result, the storage of the peripheral map information whose level is limited in the temporary storage unit 123 is repeated.

In step S220, when the amount of data exceeds the capacity threshold value (Y in step S220), the control unit 12 is the second peripheral map information stored in the temporary storage unit 123 in the width direction of the travel route. The surrounding map information of the area farther than the reference width is deleted (step S235). As a result, the free space of the temporary storage unit 123 can be increased.

Next, the control unit 12 compares the amount of data in the temporary storage unit 123 with the capacity threshold value (step S240). When the amount of data exceeds the capacity threshold value (Y in step S240), the map information management process is terminated. When the amount of data does not exceed the capacity threshold (N in step S240), the control unit 12 lowers the range of the peripheral map information of the reception unit in the width direction of the travel route up to the second distance. Control is performed so that the peripheral map information of (level 0 to level 4) is acquired from the map server 20 via the distribution processing unit 122e and the communication unit 11 and stored in the temporary storage unit 123 (step S245).

Next, the control unit 12 determines whether or not all the peripheral map information up to the destination is stored in the temporary storage unit 123 (step S250). In step S250, the peripheral map information of the area at the level of level 0 to level 4 and the length in the width direction up to the second reference width is the determination target. When all the surrounding map information up to the destination is stored in the temporary storage unit 123 (Y in step S230), the control unit 12 ends the map information management process. If the peripheral map information that is not stored in the temporary storage unit 123 remains (N in step S250), the process proceeds to step S240. As a result, the storage of the peripheral map information in the temporary storage unit 123 in which the level and the range in the width direction of the traveling route are limited is repeated.

(4) Other embodiments:
The above embodiment is an example for carrying out the present invention, and various other embodiments can be adopted. For example, the map information management system 10 may be a system realized by a plurality of devices (for example, a client and a server, a control unit in a navigation device, a control unit in a user I / F unit, and the like). A plurality of functions are provided without the search function unit 122a, the route guidance function unit 122b, the map drawing function unit 122c, the matching function unit 122d, the distribution processing unit 122e, and the map information management unit 122f that constitute the map information management system 10. It may exist separately in the device. Of course, some configurations of the above-described embodiments may be omitted, and the order of processing may be changed or omitted. For example, the map information management system 10 according to the present embodiment may have a plurality of functions, and the types and numbers of the functions are not limited to the embodiments. Preferably, the map information management system 10 may include at least two functions of the search function unit 122a, the route guidance function unit 122b, the map drawing function unit 122c, and the matching function unit 122d.

Further, the map server 20 may be capable of delivering map information of a plurality of levels having different densities of end points of road sections included in a unit area, and the number of levels and the degree of map roughness at each level are arbitrary. It can be set. Further, the plurality of levels have different amounts of information about the same area due to the difference in the density of the end points, and may be defined so that the required map information differs depending on the function.

When limiting the levels, the control unit 12 reduced the number of levels from all levels to lower levels (levels 0 to 4), but the number of levels should be reduced, and the specific number of levels is implemented. It is not limited to the form. As another example, it may be limited to higher levels.

Further, the control unit 12 has decided to perform a process of limiting the number of levels stored in the temporary storage unit 123, but it is sufficient to perform a process of reducing the amount of data per unit area of the peripheral map information for that purpose. The specific process is not limited to the process of limiting the number of levels. As another example, the control unit 12 may perform processing such as deleting predetermined information in the map information regardless of the level.

Further, when the data amount of the peripheral map information exceeds the capacity threshold, the control unit 12 reduces at least one of the data amount per unit area of the peripheral map information and the size of the region in the width direction of the traveling route. You just have to control it.

Further, the control unit 12 may limit the levels stepwise, such as first limiting all levels to levels 0 to 4, and then limiting only to level 0. Similarly, the control unit 12 may gradually limit the size in the width direction, such as narrowing the size in the width direction from the first reference width to the second reference width, and further narrowing the size to the third reference width.

Further, in the first embodiment, the control unit 12 limits the number of levels when the first estimated value exceeds the capacity threshold value, and further, without comparing the second estimated value with the capacity threshold value. A process may be performed to reduce the size of the traveling path in the width direction. Similarly, in the second embodiment, when the amount of data in the temporary storage unit 123 exceeds the capacity threshold value, the control unit 12 not only deletes the lower level peripheral map information, but also further widths the travel route. After performing the process of narrowing the distance in the direction from the first distance to the second distance, the peripheral map information of the subsequent reception unit may be saved.

Further, in the first embodiment, when the first estimated value is larger than the capacity threshold value, the control unit 12 first obtains an estimated value when the size in the width direction of the traveling path is reduced, and the estimated value is the capacity. If the threshold is exceeded, the number of levels may be further limited. Similarly, in the second embodiment, the control unit 12 first deletes the map information of the region farther than the second reference width in the width direction of the traveling route of the peripheral map information stored in the temporary storage unit 123, and then again. The number of levels may be limited when the capacity threshold is exceeded.

When the distance of the traveling route exceeds a predetermined distance such as 1000 km, the control unit 12 determines the amount of data per unit area of the surrounding map information and the size of the region in the width direction of the traveling route without obtaining an estimated value. At least one may be restricted. Specifically, when the distance of the traveling path exceeds a predetermined distance, the control unit 12 performs the following processing. That is, the control unit 12 acquires the peripheral map information in which the amount of data is reduced by performing at least one of the two processes of reducing the number of levels and reducing the area size in the width direction.

In addition, another example will be described. For example, there is a large difference in the amount of map information data per unit area between mountainous areas and urban areas. Therefore, the map information management system 10 may calculate an estimated value of the data of the peripheral map information according to whether the traveling route passes through the mountainous area or the urban area. For example, in the map information management system 10, it is assumed that different unit data amounts are set in advance for each of the mountainous area and the urban area. Further, in the map information stored in the map server 20, for example, it is assumed that information indicating whether the map is a mountainous area or an urban area is associated with each link. When the map information management system 10 acquires a travel route, it also receives information associated with the link indicating whether it is a mountainous area or an urban area. Then, the map information management system 10 specifies the distance passing through the mountainous area and the distance passing through the urban area in the traveling route based on the information indicating whether the area is a mountainous area or an urban area, and determines the distance through the mountainous area. The unit data amount of the mountainous area may be multiplied, the unit data amount of the urban area may be multiplied by the distance of the urban area, and the total of these may be obtained as an estimated value of the data amount of the entire traveling route.

The map information management system may be a mobile terminal such as a smartphone. In this case, the mobile terminal may use the position specified by the mounted GNSS as the current location of the vehicle.

Further, the functions of the distribution processing unit and the map information management unit of the map information management system may be realized by the control unit 22 of the map server 20. In this case, the control unit 22 receives the acquisition request when the acquisition request for the peripheral map information is generated by the function of the search function unit 122a. Then, the control unit 22 compares the first estimated value and the capacity threshold value of the data amount of the peripheral map information related to the acquisition request with the second estimated value and the capacity threshold value, and based on the comparison result between the second estimated value and the capacity threshold value, sets the map information to be distributed. Limit the range in the width direction of the level and travel route. Then, the control unit 22 controls the distribution processing unit to distribute the map information of the level and range of the distribution target to the system having a plurality of functions. That is, the control unit 22 transmits the map information of the level to be distributed to the system having a plurality of functions by the function of the distribution processing unit.

Further, the system, program, and method as described above may be realized as a single device or may be realized by using a shared component in a plurality of devices, and include various aspects. In addition, some of them are software and some of them are hardware, which can be changed as appropriate. Further, the invention is also established as a recording medium for a program that controls a system. Of course, the recording medium of the program may be a magnetic recording medium or a semiconductor memory, and any recording medium to be developed in the future can be considered in exactly the same way.

10 ... Map information management system, 11 ... Communication unit, 12 ... Control unit, 13 ... Recording medium, 20 ... Map server, 121 ... Map information management program, 122a ... Search function unit, 122b ... Route guidance function unit, 122c ... Map Drawing function unit, 122d ... Matching function unit, 122e ... Distribution processing unit, 122f ... Map information management unit, 123 ... Temporary storage unit

Claims (8)

A distribution processing unit that controls the distribution of map information around the vehicle's travel route from the map server,
A map information management unit that manages the surrounding map information so that it is stored in the temporary storage unit,
With
When the peripheral map information of the second travel route, which has a larger amount of data of the peripheral map information than the first travel route, is stored in the temporary storage unit, the peripheral map information of the first travel route is temporarily stored. Map information management in which at least one value of the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the size of the area in the width direction of the traveling route is smaller than that in the case of being stored in the unit. system. The map server stores a plurality of levels of map information having different densities of end points of road sections included in a unit area.
When the peripheral map information of the second traveling route is stored in the temporary storage unit, the temporary storage is compared with the case where the peripheral map information of the first traveling route is stored in the temporary storage unit. The map information management system according to claim 1, wherein the number of the levels of the peripheral map information stored in the storage unit is small. A distribution processing unit that controls the distribution of map information around the vehicle's travel route from the map server,
A map information management unit that manages the surrounding map information so that it is stored in the temporary storage unit,
With
When the peripheral map information of the data amount exceeding the capacity threshold of the temporary storage unit is stored in the temporary storage unit, compared with the case where the peripheral map information of the data amount not exceeding the capacity threshold is stored in the temporary storage unit. A map information management system in which at least one of the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the size of the area in the width direction of the traveling route is small. The map server stores a plurality of levels of map information having different densities of end points of road sections included in a unit area.
When the peripheral map information of the data amount exceeding the capacity threshold is stored in the temporary storage unit, the peripheral map information of the data amount not exceeding the capacity threshold is stored in the temporary storage unit. The map information management system according to claim 3, wherein the number of the levels of the peripheral map information stored in the temporary storage unit is small. The map information management system according to claim 3 or 4, wherein the map information management unit determines whether or not the amount of data exceeds the capacity threshold value based on the length of the traveling route. The distribution processing unit controls so that a part of the peripheral map information is sequentially distributed from the starting point of the traveling route to the destination.
The peripheral map information is partially stored in the temporary storage unit.
When the amount of data of the peripheral map information stored in the temporary storage unit exceeds the capacity threshold, the amount of data of the peripheral map information stored in the temporary storage unit per unit area and the peripheral map information The map information management system according to claim 3, wherein at least one of the sizes of the included regions in the width direction of the traveling route is controlled to be smaller. Computer,
Distribution processing unit that controls the distribution of map information around the vehicle's travel route from the map server,
Map information management unit that manages the surrounding map information so that it is stored in the temporary storage unit,
To make it work
When the peripheral map information of the second travel route, which has a larger amount of data of the peripheral map information than the first travel route, is stored in the temporary storage unit, the peripheral map information of the first travel route is temporarily stored. Map information management in which at least one value of the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the size of the area in the width direction of the traveling route is smaller than that in the case of being stored in the unit. program. Computer,
Distribution processing unit that controls the distribution of map information around the vehicle's travel route from the map server,
Map information management unit that manages the surrounding map information so that it is stored in the temporary storage unit,
To function as
When the peripheral map information of the data amount exceeding the capacity threshold of the temporary storage unit is stored in the temporary storage unit, compared with the case where the peripheral map information of the data amount not exceeding the capacity threshold is stored in the temporary storage unit. A map information management program in which at least one of the amount of data per unit area of the peripheral map information stored in the temporary storage unit and the size of the area in the width direction of the traveling route is small.

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