JP2016048238A - Navigation system, navigation method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation system, navigation method, and program with which safety of a user can further be improved.SOLUTION: A visible map creation part 11 extracts, on the basis of three-dimensional map information provided from a geographical information system 2, landmarks the positions of the presence of which can be perceived by each of a plurality of nodes in a road network on a map, for each of the nodes. A route searching part 12 searches for a route that makes it possible to move between the nodes from a departure point to a destination so as to reduce the number of the landmarks to be road signs and the frequency of switching on the basis of the landmarks for the respective nodes extracted by the visible map creation part 11.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a navigation system, a navigation method, and a program.

  Navigation systems have become common as services provided to mobile devices such as smartphones. Many people use this service, including pedestrians and motorcycle drivers. However, there is a problem that the attention to the surroundings of the user is lessened by watching the screen of the mobile device while the user is moving.

  There are two methods for confirming the correctness of the current route safely without reconfirming the map information displayed on the navigation screen of the mobile device. Landmark) is used.

  The former method is effective for use in an automobile in which voice can be easily heard. However, when this method is applied to a pedestrian and a two-wheeled vehicle driver, surrounding voice information is cut off, and an undesirable situation occurs in terms of safety.

  The latter method is a method of confirming the route by allowing the user to recognize in advance landmarks that can be seen on the route. This method has long been used when guiding routes. For example, what uses a post office, a convenience store, a high-rise building, etc. as a landmark is frequently seen in a guide map of a store or the like. According to this method, the user can check the course while looking closely at the surroundings, so that the user's safety is less likely to be lost.

  For the user, it is better that the number of landmarks and the switching frequency are small. Therefore, in the guidance method using landmarks, it is desirable to consider the visibility of the landmarks at the same time, unlike the route search method focusing only on the distance of the route.

  Various methods have been proposed for performing a route search in consideration of landmark visibility (see, for example, Patent Document 1, Non-Patent Documents 1 and 2). Patent Document 1 discloses a technique that uses an object with high visibility as a landmark and takes an approach aiming at a purpose by instructing a turning angle by sound. However, Patent Document 1 does not have a specific description of a specific visibility calculation method, a route search method, a method for instructing a corner other than sound, and the like. The method described in Non-Patent Document 1 takes an approach of considering a continuous visibility with respect to a certain landmark and searching for a destination while switching a plurality of landmarks when searching for a route. In this method, consideration is given to the difference in the appearance of a store or the like used as a landmark between day and night, and a contrivance is made to switch a landmark used as a signpost according to the time of guidance.

  In addition, there is a report that it can lead to a pedestrian to be able to see buildings that are landmarks continuously (for example, see Non-Patent Document 2). Furthermore, when searching for the shortest route, route search by Dijkstra method is performed on information on a small road network composed of several hundred intersections (see, for example, Non-Patent Document 3). Although the Dijkstra method is very useful as a route search algorithm in which only the distance is given between nodes, it is a method of sequentially determining the route, so the number of landmarks used for guidance in the entire route is determined. Difficult to minimize.

  From the above, a new device is required to perform a route search in consideration of landmark visibility on a road network of practical scale composed of tens of thousands of nodes. In addition, as a route search method considering visibility, a route search system considering landscape visibility has been proposed (for example, see Non-Patent Document 4). In this system, the visibility of the landscape from the route is measured, and the route is determined by ranking the route where the same landscape (for example, Mt. Fuji) is continuously viewed.

  In the method disclosed in Non-Patent Document 4, a route search is performed based on the visibility of landmarks that change due to factors such as weather and time. The route search considering the nature is not performed.

JP 2007-139425 A

Keisuke Nakazawa and Kenichi Okada, “Dynamic Guide Map Generation Based on Landmark Visibility”, Transactions of Information Processing Society of Japan, Vol. 48, No. 1, 2008. Hiroto Udo and Hiroshi Furukawa, “Route Search Algorithm to Reduce Pedestrian Anxiety Based on Landmark Quantitative Evaluation (Automobile Driving / Location Information / Communication Technology)”, Symposium Mobile Research Papers 2010, 27-32, 2010. E. W. Dijkstra, "A Note On Two Problems In Connexion Withgraphs.", NUMERISCHE MATHEMATIK, Vol. 1, No. 1, pp. 269-271, 1959. Aki Kono, Yuki Tanimura, Tsuji, Yukiko Kawai, Hiroshi Kawasaki. “Proposal of route search system considering landscape visibility”, Information Science and Technology Letters, Vol. 6, No. LK-005, pp. 351-354 , 2007.

  As described above, in the conventional navigation system, the number of landmarks that serve as guideposts for guidance and the frequency of switching are reduced, and the number of times the navigation screen is viewed is reduced, thereby improving the safety of the user. A specific method has not yet been established.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a navigation system, a navigation method, and a program that can further improve the safety of the user.

In order to achieve the above object, a navigation system according to the first aspect of the present invention provides:
A landmark extracting unit that extracts, for each of the nodes, a landmark that can perceive an existing position as a signpost at each of a plurality of nodes in a road network on the map based on the three-dimensional map information provided from the geographic information system;
Based on the landmarks for each node extracted by the landmark extraction unit, search for a route that can move between the nodes from the departure point to the destination so as to reduce the number of landmarks and the switching frequency. A route search unit to
Is provided.

The landmark extraction unit
Dividing the map into a plurality of regions;
Select a plurality of landmarks for each area in order of height,
From the selected landmarks, the landmarks are extracted in descending order of visibility for each of the nodes.
It is good as well.

The landmark extraction unit
Generating 3D computer graphic image data from each of a plurality of nodes based on the 3D map information provided from the geographic information system;
Rendering an image of the landmark in the generated three-dimensional computer graphic image data;
Based on the rendered landmark, determine the visibility of the landmark;
Based on the obtained visibility, a landmark that is visible from each of the plurality of nodes is extracted for each of the nodes.
It is good as well.

The landmark extraction unit
Based on the information about the landmark posted on the Internet and the position information where the information is posted, the range where the location of the landmark can be perceived is obtained, and the value corresponding to the visibility of the landmark is determined. To
It is good as well.

The route search unit
Visibility of landmarks selected as guideposts for each of a plurality of nodes passing from the starting point to the destination,
Switching frequency of landmarks between adjacent nodes,
So that the value of the cost function with
Search for a route from the starting point to the destination,
It is good as well.

The route search unit
Further adding the distance of the route from the starting point to the destination as the cost of the cost function, and searching for a route from the starting point to the destination.
It is good as well.

The route search unit
Search for a route from the starting point to the destination using an optimization algorithm;
It is good as well.
In the following embodiment, a genetic algorithm is used, but other algorithms may be used as long as the algorithm repeats generation and evaluation of solution candidates. As an algorithm to optimize by generating and evaluating candidate solutions through trial and error in this way, a single point search algorithm such as a random method, a simplex method, a hill climbing method, an annealing method, a tabu search, or the like, Examples include multi-point search algorithms such as genetic algorithms, particle swarm optimization, and ant colony optimization.

The landmark extraction unit
A planar shape that can be recognized by the plurality of nodes based on at least one of three-dimensional map information provided from the geographic information system, information on a feature posted on the Internet, and position information on which the information is posted. Landmarks, linear landmarks straddling a plurality of nodes, and spot-like landmarks recognizable at each node are extracted as landmarks.
It is good as well.

The route search unit
Searching for a route that can move between the node from the starting point to the destination while continuously recognizing the linear or planar landmark as a signpost,
It is good as well.

The route search unit
Extract highly visible features on the linear landmarks as dotted landmarks,
Extracting a path connecting the spot-like landmarks and the planar landmarks as a new linear network;
It is good as well.

The landmark extraction unit
Based on the information about the prominence of landmarks included in the three-dimensional map information provided from the geographic information system, the linear landmark is used as a landmark that can be recognized as a signpost across a plurality of nodes. Extract,
It is good as well.

The route search unit
For the route from the departure point to the point that satisfies the predetermined condition, search for the route by giving priority to the planar or linear landmark with high visibility,
For the route from the point to the destination, the route is searched by giving priority to the remaining landmarks and dotted landmarks among the planar or linear landmarks.
It is good as well.

The route search unit
When a landmark that presents guidance information as a planar landmark is within a predetermined distance, the landmark information is presented as a dotted landmark, and the guidance information is presented.
It is good as well.

The route search unit
Generating information for presenting the guide information to the presentation device or the landmark capable of perceiving the guide information at each node, and transmitting the information to the device for presenting the information;
It is good as well.

The navigation method according to the second aspect of the present invention is:
A landmark extracting step of extracting, for each of the nodes, a landmark capable of perceiving an existing position as a signpost at each of a plurality of nodes in the road network on the map based on the three-dimensional map information provided from the geographic information system;
Based on the landmarks for each node extracted by the landmark extraction unit, search for a route that can move between the nodes from the departure point to the destination so as to reduce the number of landmarks and the switching frequency. A route search step to
including.

The program according to the third aspect of the present invention is:
Computer
A landmark extraction unit that extracts, for each node, a landmark that can perceive its position as a signpost at each of a plurality of nodes in a road network on the map, based on the three-dimensional map information provided from the geographic information system;
Based on the landmarks for each node extracted by the landmark extraction unit, search for a route that can move between the nodes from the departure point to the destination so as to reduce the number of landmarks and the switching frequency. A route search unit,
And make it work.

  According to the present invention, it is possible to guide a user along a route that can move between the node from the departure point to the destination while continuously recognizing the same landmark having a high visibility as a guidepost. For this reason, since the number of landmarks that serve as guideposts and the frequency of switching can be reduced during guidance, the number of times the screen is viewed can be reduced and the safety of the user can be increased.

It is a block diagram which shows the schematic structure of the navigation system which concerns on Embodiment 1 of this invention. It is a block diagram which shows the hardware constitutions of a computer. It is a block diagram which shows the function structure of a computer. It is a figure which shows the example which divides | segments an area | region into a block. It is a figure which shows an example of the selected landmark. It is a figure which shows the selection method of the landmark in each node. FIG. 7A is a diagram illustrating an example of a landscape viewed from a node, and FIG. 7B is a diagram illustrating an example of a rendered three-dimensional CG image. It is a figure which shows an example of the route search by a landmark. It is a figure which shows an example of the selection range of a path | route. It is a flowchart of a visible map production | generation process. It is a flowchart of a route search process. It is a figure which shows an example of the determined path | route. It is a figure which shows an example of the path | route guided with the navigation system which concerns on Embodiment 3 of this invention. It is a figure which shows the example of an algorithm which searches specifically the path | route guided with the navigation system which concerns on Embodiment 3 of this invention. It is a figure which shows a dotted | punctate, linear, and planar landmark. It is a figure which creates a new linear landmark from a planar landmark and a dotted landmark. It is a figure which shows the route network which added the new linear landmark. It is a figure which shows an example of the route guidance by a dotted | punctate, linear, and planar landmark. It is a flowchart of the route search process of the navigation system which concerns on Embodiment 3 of this invention. It is a block diagram which shows schematic structure of the navigation system which concerns on Embodiment 4 of this invention. It is a block diagram which shows the function structure of the server of the navigation system of FIG. It is a flowchart which shows operation | movement of the server (route search process) of the navigation system which concerns on Embodiment 5 of this invention. It is a block diagram which shows schematic structure of the navigation system which concerns on Embodiment 6 of this invention. It is a block diagram which shows the function structure of the server of the navigation system of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 FIG.
First, a first embodiment of the present invention will be described.

  FIG. 1 shows a schematic configuration of the navigation system 100. As shown in FIG. 1, the navigation system 100 includes a server computer (server) 1, a geographic information system 2, and a mobile terminal 3. The server 1, the geographic information system 2, and the mobile terminal 3 are connected via a communication network 4 so that they can communicate with each other.

  The server 1 searches for a route from the departure point to the destination. The geographic information system 2 provides the server 1 with GIS (Geographic Information System) data for searching for a route in the server 1. The portable terminal 3 is a communication terminal such as a smartphone carried by a user. The server 1 searches for a route from the departure place to the destination in response to a request from the mobile terminal 3.

  As illustrated in FIG. 2, the server 1 includes a control unit 31, a main storage unit 32, an external storage unit 33, an operation unit 34, a display unit 35, and a communication unit 36. The main storage unit 32, the external storage unit 33, the operation unit 34, the display unit 35, and the communication unit 36 are all connected to the control unit 31 via the internal bus 30.

  The control unit 31 includes a CPU (Central Processing Unit) and the like. The CPU executes the program 39 stored in the external storage unit 33, thereby realizing each component of the server 1 shown in FIG.

  The main storage unit 32 is composed of a RAM (Random-Access Memory) or the like. The main storage unit 32 is loaded with a program 39 stored in the external storage unit 33. In addition, the main storage unit 32 is used as a work area (temporary data storage area) of the control unit 31.

  The external storage unit 33 includes a nonvolatile memory such as a flash memory, a hard disk, a DVD-RAM (Digital Versatile Disc Random-Access Memory), and a DVD-RW (Digital Versatile Disc ReWritable). In the external storage unit 33, a program 39 to be executed by the control unit 31 is stored in advance. Further, the external storage unit 33 supplies data used when executing the program 39 to the control unit 31 in accordance with an instruction from the control unit 31, and stores the data supplied from the control unit 31.

  The operation unit 34 includes a pointing device such as a keyboard and a mouse, and an interface device that connects the keyboard and the pointing device to the internal bus 30. Information regarding the content operated by the operator is input to the control unit 31 via the operation unit 34.

  The display unit 35 is composed of a CRT (Cathode Ray Tube), an LCD (Liquid Crystal Display), or the like. When the operator inputs operation information, an operation screen is displayed.

  The communication unit 36 includes a serial interface or a parallel interface. The communication unit 36 is connected to the geographic information system 2 and the portable terminal 4 via the communication network 3.

  Various components of the server 1 shown in FIG. 1 include a program 39 shown in FIG. 2 that includes a control unit 31, a main storage unit 32, an external storage unit 33, an operation unit 34, a display unit 35, a communication unit 36, and the like as hardware resources. It demonstrates its function by being used as a.

  The mobile terminal 3 also includes the hardware configuration shown in FIG. 2, and the functions of the mobile terminal 3 are realized by executing the program.

  As shown in FIG. 3, the server 1 having the hardware configuration as shown in FIG. 2 includes a storage unit 10, a visible map generation unit 11, and a route search unit 12, as shown in FIG.

  The visible map generation unit 11 as a landmark extraction unit acquires the GIS data 20 from the geographic information system 2 and stores it as the GIS data 15 in the storage unit 10. Based on the GIS data 15, the visible map generation unit 11 extracts, for each node, a plurality of nodes in the road network on the map, for example, landmarks that can be visually recognized from the intersection, on the condition of the visibility.

  The GIS data is 3D map information provided from the geographic information system 2. The GIS data includes three-dimensional data such as buildings, roads, and terrain in a target area (for example, a certain city). By using this GIS data, it is possible to draw a three-dimensional computer graphics (3DCG) image of an object that is visible from an arbitrary point in the target area. Note that objects to be drawn include buildings, terrain, roads, tracks, and the like.

  The visibility can be the occupancy rate of the landmark pixels in the entire three-dimensional computer graphics (3DCG) image. The visibility represents the visibility of the landmark from the node.

  Based on the GIS data 15, the visible map generator 11 divides the target rectangular area map into a plurality of areas, for example, 1 km square blocks, as shown in FIG.

  Subsequently, the visible map generation unit 11 selects, for each block, the top n buildings in order from the highest among the buildings included in each block. The selected landmark data is the landmark data 16 stored in the storage unit 10. The reason for selecting a landmark from each block is to prevent the landmark from being selected in the center of the city. n is set to an appropriate numerical value according to the state of the city to be generated. In FIG. 5, the landmarks selected in this way are highlighted.

  After selecting n landmarks for each block, the visible map generation unit 11 extracts landmarks with high visibility from the selected landmarks for each intersection as a node, and visually recognizes from each node. A visibility database 17 is generated that stores the possible landmarks for each node under the condition of visibility.

  When generating the visibility database 17, the visible map generation unit 11 generates a 3DCG image overlooking the entire circumference from each of all nodes (intersections) based on the GIS data 15, and includes the image in the image. To extract the landmarks. As shown in FIG. 6, landmarks that are visible from a certain node (intersection) are extracted, and invisible landmarks are not extracted.

  More specifically, the visible map generation unit 11 assigns a unique number to each determined landmark, and renders an image of all landmarks in the 3DCG image using individual colors corresponding to each number. The visible map generation unit 11 renders other buildings and backgrounds in a single color as shown in FIGS. 7A and 7B. By examining the pixel value (color) included in the rendered image, the landmark number that can be seen from a certain node (intersection) can be detected. The visible map generation unit 11 obtains the visibility of the landmark based on the rendered landmark. Furthermore, the visible map generation unit 11 extracts, for each node, landmarks that can be viewed from each of the plurality of nodes based on the obtained visibility. At this time, a landmark with a too low visibility may be prevented from being drawn on the screen. As a method for calculating the visibility, the proportion of the target landmark in the screen can be used. Further, the visibility may be calculated by perturbing the viewpoint, and the worst value may be used.

  Based on the information stored in the visibility database 17, that is, the extracted landmarks for each node, the route search unit 12 aims at the destination from the departure point while continuously viewing the same landmark with a high visibility as a signpost. Search for routes that can move between nodes to the ground. In the route search, a cost function that introduces the visibility of landmarks used as guideposts and the frequency of landmark switching between nodes as a cost is introduced.

ここで、上記式（１）の右辺第１項は、ある経路を構成する各ノードで選択されたランドマークの可視率の合計である。すなわち、ここでは、出発地から目的地までに通過する複数のノード各々について、道標として選択されたランドマークの可視率をコストとしている。また、右辺第２項は、隣接ノードの正規化項である。ノード間で参照するランドマークの切り替えがあった場合には、Ｒ_e＝１となり、切り替えがなかった場合には、Ｒ_e＝０となる。すなわち、右辺第２項は、ノード間でランドマークの切り替え頻度をコストとし、切り替え頻度が多くなればなるほど値が大きくなる。λは重み係数である。 A cost function that takes into account the visibility of the landmark is used. Here, a route point list of N points for moving from the point i to the point j is expressed as T (p) = {i,..., Tp,. The cost function C (T (p)) of the path T (p) is expressed by the equation (1).

Here, the first term on the right side of the above formula (1) is the total visibility of the landmarks selected at each node constituting a certain route. That is, here, for each of a plurality of nodes passing from the departure place to the destination, the visibility of the landmark selected as a guidepost is used as the cost. The second term on the right side is a normalization term of the adjacent node. When the landmark to be referenced is switched between the nodes, R _e = 1, and when there is no switching, R _e = 0. That is, the second term on the right side uses the frequency of switching landmarks between nodes as a cost, and the value increases as the switching frequency increases. λ is a weighting factor.

  The route search unit 12 uses the above equation (1) as a cost function and searches for an optimal route from the departure point to the destination using a genetic algorithm (GA) so that the value of the cost function is minimized. To do. FIG. 8 shows the relationship between such a route e connecting each node ν and landmarks (A, B, C, D, E) at each node ν. As shown in FIG. 8, the landmarks selected at each node are C, C, C, E, and E so that the landmarks at adjacent nodes are as continuous as possible.

  Practical scale road network information is enormous. Therefore, the route search unit 12 generally uses a method of narrowing down the route search range in advance according to the positions of the departure point and the destination. In particular, the route search by GA is characterized in that the search efficiency is improved by limiting the change due to mutation of route information to a certain range, and the search range narrows down effectively. Therefore, here, as shown in FIG. 9, only nodes (intersections) within a distance d from the line segment connecting the departure point and the destination are used for the route search. Here, if the length of the line segment connecting the starting point and the destination is Length, d = Length / 4.

  Next, the operation of the navigation system 100 will be described.

  FIG. 10 shows the flow of the visible map generation process performed in the navigation system 100. As shown in FIG. 10, first, the visible map generation unit 11 acquires the GIS data 20 from the geographic information system 2 and stores it in the storage unit 10 as the GIS data 15 (step S1). Subsequently, the visible map generator 11 divides the rectangular area defined in the GIS data 15 into a plurality of blocks (step S2). Subsequently, the visible map generation unit 11 selects the top n buildings as the landmarks in descending order for each block (step S3). Information on the selected landmark is stored in the storage unit 10 as landmark data 16.

  The visible map generator 11 generates a three-dimensional CG image at each node (each intersection) in the road network included in the GIS data 15 (step S4). Further, the visible map generator 11 renders each landmark in the three-dimensional CG image (step S5). The visible map generator 11 calculates the visibility of each rendered landmark (step S6). The visible map generation unit 11 generates a visibility database 17 that stores the landmarks in association with each node, and stores them in the storage unit 10 (step S7). After step S7 is completed, the visible map generation process ends.

  FIG. 11 shows the flow of a route search process performed in the navigation system 100. As shown in FIG. 11, first, the route search unit 12 acquires a departure point and a destination from the navigation application 50 of the mobile terminal 5 (step S <b> 11). Subsequently, the route search unit 12 selects a plurality of parent generation route candidates T (p) (step S12). Subsequently, the route search unit 12 calculates a cost function for each of a plurality of route candidates T (p) of the current generation (step S13). Subsequently, the route search unit 12 generates a plurality of child generation route candidates T (p) by a genetic algorithm (GA) (step S14). In GA, the path candidate T (p) is used as an individual to perform crossover (recombination) and mutation to generate a child generation path candidate T (p). It is to be noted that an individual that is the best in the parent generation is left as it is as an individual of the child generation.

  Subsequently, the route search unit 12 determines whether or not the value of the cost function has converged within a certain range (step S15). This is a so-called end-of-search determination. The determination condition for the end determination may be that the number of generations is a predetermined number, or that the value of the cost function is below a threshold value.

  When it is determined that the value of the cost function has not converged (step S15; No), the route search unit 12 returns to step S13 and calculates the cost function in the child generation (step S13). The generation of the child generation path candidate T (p) (step S14) and the cost function convergence determination (step S15) are repeated.

If the cost function is determined to have converged (step S15; Yes), the route search unit 12 is the most cost function to store determined by the storage unit 10 a good path candidate T _p as the final route (step S16). Subsequently, the route search unit 13 outputs the stored route T _p (step S17) and ends the process. FIG. 12 shows an example of the path generated in this way. In the route shown in FIG. 12, the number of landmarks to be referred from the starting point to the destination is only three.

  As described above in detail, according to this embodiment, it is possible to guide from the departure point to the destination by an optimal route so that the landmark with high visibility can be moved while being continuously viewed. For this reason, since the number of landmarks used for guidance and the switching frequency can be reduced, the safety of the user can be improved.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described.

  This embodiment is different from the first embodiment in the cost function. In this embodiment, the following cost function is used.

右辺第３項は、距離に応じて増加する項である。Dist（T_p、T_p+1）は、ノードT_pからノードT_p+1までの距離であり、W（ｐ）はその距離の重みである。このように、この実施の形態では、ランドマークだけでなく、経路の距離も考慮して、経路が探索される。すなわち、経路探索部１２は、出発地から目的地までの経路の距離をコスト関数のコストとしてさらに加えて、出発地から目的地までの経路を探索する。

The third term on the right side is a term that increases with distance. Dist (T _p , T _{p + 1} ) is a distance from the node T _p to the node T _{p + 1} , and W (p) is a weight of the distance. Thus, in this embodiment, a route is searched in consideration of not only the landmark but also the distance of the route. That is, the route search unit 12 further adds the distance of the route from the departure point to the destination as the cost of the cost function, and searches for the route from the departure point to the destination.

  In this way, it is possible to search for a route with a short distance in consideration of the visibility of the landmark.

Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described.

  The navigation system 100 according to each of the embodiments described above guides a route that uses a landmark with a high visibility as a landmark. In the navigation system 100 according to this embodiment, not only planar landmarks observed from a wide area on a map such as a building, but also linear landmarks such as railways, streets, and highways, and convenience stores. Point landmarks that are highly visible features on linear landmarks such as gas stations, banks, police boxes, parks, theme parks, etc. are also used as signposts.

  Based on the GIS data 15, the visible map generation unit 11 extracts linear landmarks and dotted landmarks in addition to landmarks included in the target region with high visibility. There are various methods for extracting linear landmarks and dotted landmarks. For example, railroad tracks, streets, highways, parks, theme parks are famous, and are the places where Twitter writes are sent. In such a case, the landmark is registered in the server 1 in advance, and it is determined by determining whether or not the registered linear or dotted landmark exists in the target area. be able to. That is, the visible map generation unit 11 uses linear or dotted landmarks as landmarks that can be recognized as landmarks across a plurality of nodes for landmarks included in the GIS data 15. Extract. For example, famous national highways, highways, famous highways, shopping streets, parks, ballparks, etc. can be such landmarks.

  The visible map generation unit 11 stores the extracted linear and dotted landmarks in the landmark data 16. Based on the GIS data 15, the visible map generation unit 11 sets a landmark that can be recognized as a guidepost across a plurality of nodes in the road network on the map as a linear or planar landmark for each node. Extract. The route search unit 12 detects a route that can move from the starting point to the destination while continuously recognizing not only a planar landmark with high visibility but also a linear or dotted landmark as a guidepost. Explore. The route search unit 12 searches for a route that minimizes the number of landmarks as signposts.

  For example, as shown in FIG. 13, when there is a tram line as a linear landmark on the route, the tram line is selected as a landmark to be used for guidance, and while it is on the landmark, the landmark By moving up, it is possible to make a tram line a common landmark among a plurality of adjacent nodes. As a result, the value of the cost function can be improved.

  A specific route search method using surface, line, and dotted landmarks will be described with reference to FIGS. First, as illustrated in FIG. 14, the route search unit 12 generates a Bounding Box including two points based on the information of the departure place and the destination. Next, as shown in FIG. 15, the route search unit 12 uses the dotted landmark (square), the linear landmark (thick solid line), and the planar landmark (small circle) included in the Bounding Box. select. Here, the great circle shown in the figure (hereinafter referred to as a planar landmark visible area) indicates a range in which the planar landmark is visible, and there is one for each small circle.

  Next, a method for determining a new linear landmark from dot-like and planar landmarks will be described with reference to FIG. First, the route search unit 12 connects each planar landmark and the dotted landmark existing within the visible area of the planar landmark with a line. At this time, it is assumed that the departure place is also included in the dotted landmark. This line becomes a new linear landmark (thick dashed line). At this time, when a new linear landmark and an existing landmark intersect, the intersection becomes a new dotted landmark (indicated by a triangle in FIG. 16). That is, the route search unit 12 extracts a highly visible feature on a linear landmark (solid line in FIG. 16) as a dotted landmark (square in FIG. 16) and extracts the dotted landmark. A route connecting the (square) and the planar landmark (small circle) is extracted as a new linear network (broken line). The route search unit 12 extracts an intersection of a network on a line (solid line) and a new linear network (broken line) as a new dotted network (triangle). This is performed for all planar landmarks. Finally, add the destination to this road network. As an additional method, a new node may be inserted into the road network in the vicinity of the destination.

  FIG. 17 shows a road network using only the landmarks generated in this way. FIG. 18 shows an example of a result of route search by a network using only the landmark. By introducing linear or dotted landmarks in this way, it is possible to efficiently obtain a route that can reach the destination with a small number of landmarks even with a slight detour. Furthermore, the introduction of linear landmarks in this way also has the advantage that the scale of the road network used for route search can be reduced.

  FIG. 19 shows a flowchart up to this point. As shown in FIG. 19, the server 1 designates a starting point / destination, that is, a start / goal designation (see step S 21, FIG. 14), a bounding box generation (step S 22, see FIG. 14), a point / line / plane. A landmark is determined (step S23, see FIG. 15), a road network is generated (see step S24, FIG. 16, FIG. 17), and a route search (step S25, see FIG. 18) is performed in this order. In the road network generation (step S24), a path (dashed line) connecting the planar landmark and the dotted landmark is generated, and a new point (node (triangle) generation) where the generated path and the linear landmark intersect is generated. Is performed (see FIG. 18).

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described. In general, a landmark refers to something visually noticeable. For this reason, in the above-described embodiments, the visibility of the landmark for each node is mainly acquired by image processing or the like. On the other hand, highly prominent features that can become landmarks frequently appear in Internet posting systems such as websites, social network service (SNS) Twitter, Facebook, Instagram, etc. Appearance frequency tends to be high. Therefore, in this embodiment, information posted on Twitter, Facebook, Instagram, etc. is analyzed, and features that tend to appear frequently are used as new landmarks that cannot be estimated by visibility alone. To do.

  For example, if there is a post (writing) of “cafe with good atmosphere”, the cafe is used as a dotted landmark. Also, if there is a post “Refreshing tree-lined road”, it will be used as a linear landmark. If there is a post that says “a building of a different color that sometimes appears in the valley of a building”, it will be used as a planar landmark.

  FIG. 20 shows a schematic configuration of navigation system 100 according to the present embodiment. As shown in FIG. 20, the navigation system 100 is based on information obtained from many portable terminals 3.

  A posting system 5 is connected to the communication network 4. The posting system 5 is a server computer that manages posting information (posting data) posted from the mobile terminal 3 or the like in a location-based SNS such as a website, Twitter, or Facebook.

  The posting system 5 receives post data and GPS (Global Positioning System) data (position information) of the mobile terminal 3 when the post data is posted from the mobile terminal 3 or the like via the communication network 4. . The posting system 5 stores the received posting data and GPS data in association with each other.

  FIG. 21 shows a functional configuration of the server 1 constituting the navigation system 100 according to the present embodiment. The server 1 is the same as the first embodiment in that the server 1 includes a storage unit 10, a visible map generation unit 11, and a route search unit 12 as its functional configuration.

  The visible map generation unit 11 acquires GIS data from the geographic information system 2 and stores it in the storage unit 10, and acquires post data + GPS data 21 received from the post system 5 and stores it as post data (position information) 19. To do. Since position information such as GPS is added to the posted data, it is possible to easily detect where the posted data is posted.

  The visible map generation unit 11 generates 3D CG image data from each of a plurality of nodes based on the 3D map information provided from the geographic information system 2. Further, the visible map generation unit 11 renders an image of the planar landmark in the generated three-dimensional CG image data, and obtains and calculates the visibility of the planar landmark based on the rendered landmark. Based on the obtained visibility, planar landmarks that are visible from each of the plurality of nodes are extracted for each node.

  However, for planar landmarks, visibility is blocked by features that are not on the digital map, such as street trees, road guides, hospital and shop signs, etc., and are visible by simulation, CAD (Computer Aided Design) models, and image processing. Sometimes the rate calculation is not always correct. Therefore, in such a case, the visible map generation unit 11 uses post data (position information) 19 posted on the Internet, such as Twitter, Facebook, and Instagram. Specifically, the visible map generation unit 11 is based on the posted data and the position information on which the data is posted, the range in which the location of the landmark can be perceived, and the appearance frequency of the posted data in which the landmark appears. Is obtained as a value corresponding to the visibility of the landmark. The range in which the location of the landmark can be perceived is not only the range where the landmark can be directly seen, but also the range where you can see a signboard that displays “turn right to the landmark, 500 m”. Also included is a range where the location of the landmark is known.

  First, the visible map generation unit 11 collects post data and posted positions from the posting system 5 and stores them in the storage unit 10 as post data (position information) 19. Further, the visible map generation unit 11 analyzes the stored post data (position information) 19 and calculates the appearance frequency of landmarks for the post data at each position. The visible map generation unit 11 sets a position where the appearance frequency of the landmark is a predetermined value or more as a range in which the presence position of the landmark can be perceived, and uses it for selecting a landmark at each node. Further, the visible map generation unit 11 calculates the appearance frequency of the landmark at each position as a value (importance) corresponding to the visibility with respect to the landmark. The route search unit 12 uses the appearance frequency of the landmark for the route search.

  It should be noted that the visible map generation unit 11 assumes that a landmark appears in the posted data if the post data does not include a proper noun of the landmark but includes related text. The importance of the landmark may be calculated. For example, when words such as “matrix”, “tourist attraction”, and “high” co-occurring with “Sky Tree” within a certain range are included in the posting data, the visible map generation unit 11 The degree of influence of “Sky Tree” may be calculated by treating the data as post data including “Sky Tree”.

  In addition, the visibility and the visible range can be calculated by analyzing a street view image. Since the street view image is actually taken from that location, the appearance of the landmark is accurate. At this time, in order to recognize which building on the map the building included in the street view image, and to calculate the visibility and visible range of the building, for example, deep learning (deep learning) You may make it use the image recognition technique like this.

  Even if the landmark itself is not visible, information on the feature (for example, a signboard or a sign such as “to the right here”) can identify the location and direction of the feature. For example, the feature can be used as a landmark. In addition, if this is used, some landmarks can be used as landmarks covering a certain area (in other words, it can be understood as equivalent to representing a direction in a certain area). For example, in Kagoshima, the direction of Sakurajima has the same meaning as facing east, so Sakurajima can be used as a landmark on the surface representing such a direction. In Kyoto, the direction of Mt. Hiei or Arashiyama points to the northeast and southwest respectively. In Kobe, the direction of Yamate or coast points to the north and south, respectively. Even people with a sense of intuition can intuitively proceed in the right direction. In the city center, you can use the same landmark as this “perceptible direction” to determine which direction to get off at the station and proceed in the same way (for example, from Shibuya Station, Shinjuku, Like Roppongi or Ebisu).

Embodiment 5 FIG.
Next, a fifth embodiment of the present invention will be described. Even a very high-rise building with a high visibility range (planar landmark) may not be visible from a place surrounded by buildings that are somewhat high. On the other hand, even a building that is not very tall that cannot be seen from a wide area has very high visibility as long as it is within a few tens to hundreds of meters. In the present embodiment, a navigation system that guides a route by effectively utilizing such landmark characteristics will be described.

  When the landmark is selected by the threshold processing for the visibility as in each of the above embodiments, the former is selected as a planar landmark, but the latter is not selected. Therefore, the navigation system 100 according to the fifth embodiment hierarchizes the route search and switches the landmark to be used from the former to the latter.

  The configuration of navigation system 100 according to the present embodiment is the same as the configuration of navigation system 100 according to the fourth embodiment shown in FIGS.

  However, in the navigation system 100 according to the present embodiment, the visible map generation unit 11 of the server 1 performs the visible map generation process shown in FIG. 10 with a wide area (bounding box including a start point and a goal point) and a narrow area. Divide the area several times. In this way, it is possible to extract a short landmark that has not been selected in a wide area in a narrow area.

  Next, the operation of the route search unit 12 will be described.

  As shown in FIG. 22, the route search unit 12 operates in the same manner as in the third embodiment from start / goal designation (step S21) to formation of a road network (step S24).

  Subsequently, the route search unit 12 searches for a rough route (step S25). In this search, mainly planar landmarks and linear landmarks that have a high visibility and are visible in a wide range are preferentially used. In this general route search, it is often the case that short planar and linear landmarks (landmarks that do not have high visibility in the vicinity of the departure point) are not actually visible. Used.

  Thereafter, the route search unit 12 guides the searched approximate route (step S26).

  The route search unit 12 waits until the mobile terminal 3 reaches within a predetermined distance range to the destination based on the position information transmitted from the mobile terminal 3 (step S27; No). When reaching the range of the predetermined distance to the destination (step S27; Yes), the route search unit 12 searches for a detailed route from the point to the destination (step S28). In this search, mainly planar landmarks with low visibility are used preferentially. In this rough route search, a tall planar landmark is not suitable for a signpost for detailed route guidance, and is therefore used in a restrained manner.

  Thereafter, the route search unit 12 provides guidance using the searched detailed route (step S29).

  In this embodiment, the landmark used for the route search is switched depending on the distance from the current location to the destination, but the distance between the planar landmark used for the route guidance is within a predetermined distance. In such a case, the landmark may be switched to a planar, dotted, or linear landmark having a narrow viewable range for guidance. In this way, for example, at first, the Tokyo Tower that is visible from a distance is used as a planar landmark for route guidance, and when you come to the immediate vicinity of Tokyo Tower, turn right at the foot of Tokyo Tower. It is also possible to use the tower as a dotted landmark for route guidance. That is, the route search unit 12 can present the guidance information using the landmark as a dotted landmark when the landmark presenting the guidance information as a planar landmark is within a predetermined distance. it can.

Embodiment 6 FIG.
Next, a sixth embodiment of the present invention will be described with reference to FIG. In this embodiment, a navigation system useful for switching landmarks such as walking along a national road as a linear landmark and walking toward a high-rise building in the distance. explain.

  In such a switch, if there is a spot-like landmark (such as a post office) that is in contact with the linear landmark so that it can be easily understood, it can be used. it can. However, if there is no such landmark, the user may be detoured or such a route may not appear as a route search result. Therefore, in the present embodiment, the digital signage 40 (see FIG. 23) is arranged at a place where the landmark is switched, and special guidance information (guidance pattern) is actively displayed on the digital signage 40.

  As shown in FIG. 24, the navigation application 50 of the mobile terminal 3 informs the route search unit 12 of the server 1 of FIG. 23 that the route guidance is used. The route search unit 12 acquires the position information of the mobile terminal 3 of FIG. 23 using a fixed point camera, a position detection system using RFID (Radio Frequency IDentifier), WiFi (Wireless Fidelity), etc., and the mobile terminal 3 receives the digital signage 40. A special guide pattern is displayed on the digital signage 40 in accordance with the position of the position. There are various types of guidance patterns. For example, the guidance pattern may be a destination image, or may simply be a symbol (◯) indicating that the route is correct or a symbol (X) indicating that the route is incorrect. If an arrow indicating the traveling direction is displayed, the user can identify the traveling direction. Further, information on the next landmark may be displayed as the guidance pattern. In addition, a device having a speaker may be prepared in each node and guided using voice.

  Moreover, as a display of a guidance pattern, you may make it show a symbol meaningful only to a specific person. For example, it is possible to present a plurality of pieces of information to a plurality of people almost simultaneously by switching and displaying patterns one after another at certain intervals.

  By looking at such a guidance pattern, the user can grasp his / her position and can confirm the route to the destination on the display. As a result, it is not necessary for the user to check the screen of the mobile terminal 3, so that the safety of the user can be improved.

  Further, in a place where the digital signage 40 is not installed, a guidance pattern may be displayed by projection mapping. Further, the user may be notified by voice or the like.

  Furthermore, a planar landmark or the like can be used for such an active guide pattern display. Even if a planar landmark is illuminated brightly with illumination, it becomes more conspicuous than other structures, which is suitable as a landmark. In particular, since such a display is useful for improving the visibility of landmarks at night, the range of use of the navigation system 100 according to the present embodiment can be greatly expanded.

  In addition, a new planar landmark can be constructed by a system that projects laser light toward the sky, which has been attracting attention in recent years. Here, if a different guide pattern for each event or time is projected onto the sky with a laser beam, it is possible to control the flow of the person who saw the guide pattern. For example, when there is a soccer game at a certain time and many people go to the stadium from the nearest station, it may be possible to project an optimal guidance pattern that distributes people's routes so as to eliminate congestion . Further, when there is a concert at another time and the same station is the nearest station, a guidance pattern for guiding another route toward the concert hall may be projected.

  Further, in a place where the digital signage 40 is not installed, a moving object such as a person or a car may be displayed as a guide pattern display target.

  Thus, the landmark may be active. However, in actual operation, at the time of route guidance, the server 1 knows by receiving from a device that displays information such as whether these active landmarks are active or where they are located. It is necessary to keep.

  As described above, according to the navigation system according to each of the above-described embodiments, guidance is performed using everything that can be a landmark, such as a planar, linear, or dotted landmark. By using linear and dotted landmarks, more accurate and safe route guidance according to the user's situation is possible. In addition, planar, linear, and dotted landmarks are not limited to geometric things that are easy to see, but are meaningful landmarks that are easily remembered by people (such as cafes and crowds that have become a hot topic. Stores, congested roads, power spots such as temples and shrines) and their signs. Such semantic landmarks can be acquired from posted data posted on a location-based SNS such as Twitter.

  In addition, according to the navigation system according to the above-described embodiment, for example, route guidance is performed hierarchically according to how close the user is to the destination. Accordingly, guidance using landmarks that are easy to visually recognize according to the situation at that time of the user is possible, so that more accurate and safe route guidance is possible.

  Further, according to the navigation system according to the above-described embodiment, guidance information for guiding the user is presented to other things such as digital signage and landmarks on the user's route. Thereby, since the user can reconfirm the route and the like, more accurate and safe route guidance according to the user's situation is possible.

  In each of the above embodiments, the server 1 implements the functions of the landmark extraction unit (visible map generation unit 11) and the route search unit. However, the present invention is not limited to this, and the portable terminal 3 uses the landmark extraction unit and the route. You may make it implement | achieve the function of a search part. The mobile terminal 3 may be a game terminal, a mobile computer, or a personal computer. Also, a dedicated navigation device such as a car navigation device may be used. Moreover, the terminal etc. which were installed in the town may be sufficient.

  Also, the node need not be an intersection. Any point in the middle of the route may be used.

  In each of the above embodiments, the system uses the GIS service, but the present invention is not limited to this. For example, an API of Google (registered trademark) Map may be used.

  As described above, according to the present invention, it is possible for the user to check the route and his / her position as much as possible, and navigation using landmarks that are easy for humans to remember and highly visible is possible.

  In addition, the hardware configuration and software configuration of the server 1 are merely examples, and can be arbitrarily changed and modified.

  A central part that performs processing of the server 1 including the control unit 31, the main storage unit 32, the external storage unit 33, the operation unit 34, the display unit 35, the communication unit 36, the internal bus 30, and the like is a dedicated system. Regardless, it can be realized using a normal computer system. For example, a computer program for executing the above operation is stored in a computer-readable recording medium (flexible disk, CD-ROM, DVD-ROM, etc.) and distributed, and the computer program is installed in the computer. Thus, the server 1 that executes the above-described processing may be configured. Further, the server 1 may be configured by storing the computer program in a storage device of a server device on a communication network such as the Internet and downloading it by a normal computer system.

  When the functions of the server 1 are realized by sharing an OS (operating system) and an application program, or by cooperation between the OS and the application program, only the application program portion may be stored in a recording medium or a storage device. .

  It is also possible to superimpose a computer program on a carrier wave and distribute it via a communication network. For example, a computer program may be posted on a bulletin board (BBS, Bulletin Board System) on a communication network, and the computer program distributed via the network. The computer program may be started and executed in the same manner as other application programs under the control of the OS, so that the above-described processing may be executed.

  Various embodiments and modifications can be made to the present invention without departing from the broad spirit and scope of the present invention. The above-described embodiments are for explaining the present invention and do not limit the scope of the present invention. In other words, the scope of the present invention is shown not by the embodiments but by the claims. Various modifications within the scope of the claims and within the scope of the equivalent invention are considered to be within the scope of the present invention.

  1 server computer (server), 2 geographic information system, 3 mobile terminal, 4 communication network, 5 posting system, 10 storage unit, 11 visual map generation unit, 12 route search unit, 15 GIS data, 16 landmark data, 17 visible Rate database, 19 Post data (position information), 20 GIS data, 21 Post data + GPS data, 30 Internal bus, 31 Control unit, 32 Main storage unit, 33 External storage unit, 34 Operation unit, 35 Display unit, 36 Communication unit 39 programs, 40 digital signage, 50 navigation apps, 100 navigation systems.

Claims (16)

A landmark extracting unit that extracts, for each of the nodes, a landmark that can perceive an existing position as a signpost at each of a plurality of nodes in a road network on the map based on the three-dimensional map information provided from the geographic information system;
Based on the landmarks for each node extracted by the landmark extraction unit, search for a route that can move between the nodes from the departure point to the destination so as to reduce the number of landmarks and the switching frequency. A route search unit to
A navigation system comprising: The landmark extraction unit
Dividing the map into a plurality of regions;
Select a plurality of landmarks for each area in order of height,
From the selected landmarks, the landmarks are extracted in descending order of visibility for each of the nodes.
The navigation system according to claim 1. The landmark extraction unit
Generating 3D computer graphic image data from each of a plurality of nodes based on the 3D map information provided from the geographic information system;
Rendering an image of the landmark in the generated three-dimensional computer graphic image data;
Based on the rendered landmark, determine the visibility of the landmark;
Based on the obtained visibility, a landmark that is visible from each of the plurality of nodes is extracted for each of the nodes.
The navigation system according to claim 2. The landmark extraction unit
Based on the information about the landmark posted on the Internet and the position information where the information is posted, the range where the location of the landmark can be perceived is obtained, and the value corresponding to the visibility of the landmark is determined. To
The navigation system according to claim 1. The route search unit
Visibility of landmarks selected as guideposts for each of a plurality of nodes passing from the starting point to the destination,
Switching frequency of landmarks between adjacent nodes,
So that the value of the cost function with
Search for a route from the starting point to the destination,
The navigation system according to any one of claims 2 to 4. The route search unit
Further adding the distance of the route from the starting point to the destination as the cost of the cost function, and searching for a route from the starting point to the destination.
The navigation system according to claim 5. The route search unit
Search for a route from the starting point to the destination using an optimization algorithm;
The navigation system according to claim 5 or 6. The landmark extraction unit
A planar shape that can be recognized by the plurality of nodes based on at least one of three-dimensional map information provided from the geographic information system, information on a feature posted on the Internet, and position information on which the information is posted. Landmarks, linear landmarks straddling a plurality of nodes, and spot-like landmarks recognizable at each node are extracted as landmarks.
The navigation system according to any one of claims 1 to 7. The route search unit
Searching for a route that can move between the node from the starting point to the destination while continuously recognizing the linear or planar landmark as a signpost,
The navigation system according to claim 8. The route search unit
Extract highly visible features on the linear landmarks as dotted landmarks,
Extracting a path connecting the spot-like landmarks and the planar landmarks as a new linear network;
The navigation system according to claim 9. The landmark extraction unit
Based on the information about the prominence of landmarks included in the three-dimensional map information provided from the geographic information system, the linear landmark is used as a landmark that can be recognized as a signpost across a plurality of nodes. Extract,
The navigation system according to claim 9 or 10. The route search unit
For the route from the departure point to the point that satisfies the predetermined condition, search for the route by giving priority to the planar or linear landmark with high visibility,
For the route from the point to the destination, the route is searched by giving priority to the remaining landmarks and dotted landmarks among the planar or linear landmarks.
The navigation system according to claim 8. The route search unit
When a landmark that presents guidance information as a planar landmark is within a predetermined distance, the landmark information is presented as a dotted landmark, and the guidance information is presented.
The navigation system according to claim 8. The route search unit
Generating information for presenting the guide information to the presentation device or the landmark capable of perceiving the guide information at each node, and transmitting the information to the device for presenting the information;
The navigation system according to any one of claims 1 to 13. A landmark extracting step of extracting, for each of the nodes, a landmark capable of perceiving an existing position as a signpost at each of a plurality of nodes in the road network on the map based on the three-dimensional map information provided from the geographic information system;
Based on the landmarks for each node extracted by the landmark extraction unit, search for a route that can move between the nodes from the departure point to the destination so as to reduce the number of landmarks and the switching frequency. A route search step to
Navigation method including. Computer
A landmark extraction unit that extracts, for each node, a landmark that can perceive its position as a signpost at each of a plurality of nodes in a road network on the map, based on the three-dimensional map information provided from the geographic information system;
Based on the landmarks for each node extracted by the landmark extraction unit, search for a route that can move between the nodes from the departure point to the destination so as to reduce the number of landmarks and the switching frequency. A route search unit,
Program to make it work.

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