JP2009058250A - Map display device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To display a present position detected by a map display device on a proper position on a map, without using data for showing a recommendation route or a road network. <P>SOLUTION: A cellular phone as the map display device acquires map data from a map server. In the map data, graphic data showing the position and the shape of a feature, and attribute information showing the kind of the feature are recorded plurally correlatively with each other. When detecting the present position by using a GPS receiver, the cellular phone specifies a feature existing near the detected present position, where a user can exists, based on the graphic data and the attribute information. When a feature used as a correction reference for the present position is specified in this way, the cellular phone displays the present position on a prescribed position on the specified feature. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technique for displaying a current position together with a map.

  In recent years, communication-type navigation systems have been put into practical use. In the communication-type navigation system, a map display device mounted on a vehicle or the like displays a map by acquiring map data from a server using a predetermined communication means. In such a communication-type navigation system, the vehicle position information and destination point information are transmitted from the map display device to the server, and a route search is performed on the server side. The recommended route created as a result of the route search is transmitted from the server to the map display device and used for route guidance.

  The map display device performs positioning of the current position using GPS (Global Positioning System / Global Positioning System). However, it is known that an error of several meters to several tens of meters occurs in positioning using GPS. In order to correct such an error, for example, in the communication type navigation system described in Patent Document 1 or Patent Document 2, the distance between the current position measured using GPS and the recommended route received from the server is obtained. If the distance is within 200 m, the current position is displayed at a position on the recommended route. In addition, in the non-communication type map display device that stores the road data (road network data) that can be used for route search, if there is an error in the current position, the current position is displayed on the nearest road network. Processing to display is performed.

JP 2003-214858 A JP 2002-310691 A

  Since the conventional map display device is mostly mounted on a vehicle, it is a useful process to correct the current position to a recommended route or a position on a road network. However, in recent years, cellular phones, portable game machines, and portable information terminals equipped with GPS receivers can function as map display devices, and can be used not only in vehicles but also when walking. It has become. A pedestrian does not necessarily move along a recommended route or road, but may move to a place unrelated to the recommended route or road network, such as in a park or a store. In such a situation, if the current position is forcibly displayed on the recommended route or the position on the road network as in the past, the map display device may display an incorrect position on the contrary, There was a risk that the user would mistake the current position.

  Considering such problems, the problem to be solved by the present invention is to display the current position detected by the map display device at an appropriate position on the map without using the data indicating the recommended route or the road network. It is in.

  Based on the above problems, a map display device according to an aspect of the present invention is configured as follows.

A map display device according to one aspect of the present invention is provided.
A map display device that displays a current position together with a map,
For a plurality of types of features, a data acquisition unit for acquiring map data in which graphic data representing the position and shape of the features and attribute information representing the types of the features are recorded in association with each other;
A detection unit for sequentially detecting the current position;
A search unit that searches the map data based on the graphic data and the attribute information for a feature that exists in the vicinity of the detected current position and may include the current position;
A drawing unit that draws the feature represented by the graphic data and draws a display as a current position at a predetermined position on the searched feature.

  According to the map display device of the above aspect, even if there is an error in the detected current position, it is represented not by the recommended route or the position on the road network but by the graphic data for drawing the map as in the past. The current position can be displayed at a predetermined position on the feature. Therefore, even if the user deviates from the recommended route, the current position can be displayed with high accuracy. Moreover, according to the map display apparatus of the said aspect, since a present position can be displayed on the position on the feature in which the detected present position can be contained, for example, a pedestrian exists on a highway Unnatural display can be suppressed. The graphic data may be in a vector format or a raster format. Further, the current position itself may be included in the range of “near” the current position.

  The map display device according to the aspect further includes a determination unit that determines a type of the moving means of the user, and the search unit may include the current position according to the determined type of the moving means. You may specify the attribute of a feature. With such an aspect, it is possible to specify the attribute of the feature that is the display target of the current position according to the type of the moving means of the user. Therefore, it becomes possible to display the current position on a suitable feature in consideration of the moving means of the user.

  In the map display device according to the aspect described above, the determination unit may determine the type of the moving unit based on the update status of the current position that is sequentially detected. In such an aspect, for example, the average speed can be obtained from the update status of the current position that is sequentially detected, and the type of the moving means can be estimated based on the average speed. As described above, if the type of the moving unit is determined based on the current position detected sequentially, it is not necessary to perform the setting operation every time the moving unit is changed, so that the convenience for the user can be improved. Note that the type of moving means may include, for example, walking or a vehicle, and may include a bicycle, a train, a ship, an aircraft, or the like.

  In the map display device according to the aspect, the type of the feature includes a building, and the drawing unit has the predetermined position when the attribute information associated with the searched feature is the building. The display as the current position may be drawn at the center position of the building. With such an aspect, it is possible to easily recognize on the screen that the user is present in the building.

  In the map display device according to the aspect, the type of the feature includes a site, and the drawing unit includes the predetermined position when the attribute information associated with the searched feature is the site. The display as the current position may be drawn at the detected current position. If it is such an aspect, the detected present position can be displayed as it is in the site where a user can move freely, such as a golf course, a ground, and a park, for example.

  In the map display device according to the aspect described above, the type of the feature includes a road, and the drawing unit includes the predetermined position when the attribute information associated with the searched feature is the road. As another example, a display as the current position may be drawn at a position where a perpendicular drawn from the detected current position to the nearest road that is the searched feature intersects with the road. With such an aspect, the current position can be displayed at a position on the road.

  In the map display device according to the aspect described above, the drawing unit displays graphic data in which the type of the first feature that the user cannot exist is associated as the attribute information in the vicinity of the detected current position. When there is a plurality of graphic data associated with the second feature type that the user may exist as the attribute information, the graphic associated with the second feature type After drawing the display as the current position at a position on the feature represented by any one of the graphic data, the data represented by the other graphic data associated with the type of the second feature There may be provided means for restricting the display as the current position from being drawn at a position on the object.

  If it is such an aspect, for example, when the moving means is a vehicle, there are two roads across the river, or when the moving means is walking, there are two sidewalks across the highway. When present, it is possible to suppress the current position from being sequentially displayed across the central feature.

  In the map display device of the above aspect, there may be at least two or more of a water area, a site, a building, a road, a railroad, and a station as the feature type. In this way, by associating various attribute information with the graphic data, it is possible to accurately identify a feature that can include the current position.

  In the map display device according to the aspect described above, the graphic data is further associated with shape type information indicating whether the feature is represented by a line or a surface, and the drawing unit is in accordance with the shape type information. The feature may be drawn with a line or a plane. If it is such an aspect, the drawing part can specify the drawing method of a figure easily.

  In the map display device according to the aspect described above, when the shape type information corresponding to the searched feature is a surface, the drawing unit detects the current position on the feature a plurality of times. As long as it is possible, a display as the current position may be drawn at a predetermined position on the feature. With such an aspect, the current position can be displayed on the feature only when the current position is reliably detected on the feature represented by the surface.

  In the map display device according to the aspect described above, the data acquisition unit may acquire the map data from a predetermined server by wireless communication. According to such an aspect, it is not necessary to provide the map display device itself with a storage device for storing the map data, so that the device can be made compact and the manufacturing cost can be reduced. Further, by storing the map data in a predetermined server, the map data can be easily updated.

  In addition to the configuration as the map display device described above, the present invention can also be configured as a map display method or a computer program. Such a computer program may be recorded on a computer-readable recording medium. As the recording medium, for example, various media such as a flexible disk, a CD-ROM, a DVD-ROM, a magneto-optical disk, a memory card, and a hard disk can be used.

Hereinafter, embodiments of the present invention will be described in the following order based on examples.
A. Schematic configuration of map display system:
B. Route search process:
C. Map display processing:
D. Variations:

A. Schematic configuration of map display system:
FIG. 1 is an explanatory diagram showing a schematic configuration of a map display system 10 as an embodiment of the present invention. As shown in the figure, the map display system 10 of the present embodiment includes a route search server 100, a map server 150, and a mobile phone 200 as a map display device. The mobile phone 200 according to the present embodiment includes a GPS receiver 201 and has a function of performing route guidance using the GPS receiver 201. The mobile phone 200 functions as a pedestrian navigation device when carried by a person, and functions as a car navigation device when used in a vehicle.

  The mobile phone 200 includes a GPS receiver 201, a display panel 202, an audio output unit 203, a wireless communication circuit 205, a command input unit 206, a main control unit 210, and a call control unit 220.

  The main control unit 210 is a controller for controlling each unit of the mobile phone 200. The main control unit 210 includes a CPU 211, a RAM 212, and a ROM 213. The CPU 211 implements various processes to be described later by loading the control program stored in the ROM 213 into the RAM 212 and executing it.

  The GPS receiver 201 is a device that receives radio waves transmitted from artificial satellites that constitute a GPS (Global Positioning System / Global Positioning System). The main control unit 210 detects (positions) the current position based on the radio wave received by the GPS receiver 201. If the GPS receiver 201 can receive radio waves from three satellites, the main control unit 210 can detect a two-dimensional current position, and if the GPS receiver 201 can receive radio waves from four satellites, 3 A dimensional current position can be detected. In addition, if radio waves can be received from five or more satellites, the current position can be detected with high accuracy.

  The display panel 202 includes a liquid crystal display and a drive circuit that drives the liquid crystal display. The liquid crystal display has a resolution of, for example, 480 pixels × 640 pixels (VGA). The main control unit 210 controls the display panel 202 to draw a map image, a recommended route, a current position, and the like. The display panel 202 is not limited to a liquid crystal display, and various display devices such as an organic EL display can be employed.

  The voice output unit 203 includes a speaker for outputting voice during route guidance, a circuit for driving the speaker, and the like.

  The wireless communication circuit 205 is a circuit for performing data communication or voice communication with the base station BS. A route search server 100 and a map server 150 are connected to the base station BS via the Internet INT. The wireless communication circuit 205 can access the route search server 100 and the map server 150 via the base station BS.

  The call control unit 220 is a circuit that performs incoming calls and calls for voice calls, conversion of voice signals and electrical signals, and the like.

  The command input unit 206 includes a group of buttons such as a numeric keypad 206a and a cursor key 206b. By using these buttons, the user can input the starting point and destination used for route search.

  The map server 150 includes a communication unit 152, a control unit 154, and a storage device 155. The storage device 155 stores a map database 156. The communication unit 152 can communicate with the mobile phone 200 via the Internet INT. In the map database 156, map data for the mobile phone 200 to draw a map on the screen is recorded. This map data includes graphic data representing the shape of features such as buildings and roads. When there is a map data acquisition request from the mobile phone 200, the control unit 154 searches the map database 156 for map data in the specified range, and transmits the map data to the mobile phone 200 via the communication unit 152.

  FIG. 2 is an explanatory diagram showing the data structure of the map database 156. As shown in the figure, the map database 156 records graphic data representing the position and shape of features on the map in a vector format with latitude and longitude as coordinates. In the present embodiment, each coordinate constituting one feature is represented by absolute coordinates. However, of course, one coordinate may be represented by an absolute coordinate and the other coordinate may be represented by a relative coordinate.

  Each feature recorded in the map database 156 is assigned a unique number, and each feature is associated with attribute information and a figure type. The attribute information is information indicating the type of the feature. In this embodiment, any one of a water area, a site, a building, a road, a sidewalk, a railroad, and a station is associated with each feature. Each attribute is further classified into detailed attributes as indicated by “detailed attributes” in the drawing. For example, the water area is classified into a river, a lake, and the sea, and the site is classified into a golf course, an airport, a natural green space, a ground, and a leisure facility. These pieces of attribute information are divided to draw the same kind of features together.

  Each feature recorded in the map database 156 is further associated with a type of figure representing the feature. There are “line” and “surface” as graphic types. When the type is a line, the feature is represented by a line segment connecting the coordinates recorded in the graphic data. When the figure type is a plane, the feature is represented by an area surrounded by coordinates recorded in the figure data. In addition to information such as lines and surfaces, information such as the thickness and color of lines and the color of surfaces may be associated as graphic types.

  The route search server 100 includes a communication unit 102, a control unit 104, and a storage device 105. The communication unit 102 can communicate with the mobile phone 200 via the Internet INT. The storage device 105 stores a route database 106 for the mobile phone 200 to perform route guidance. In the route database 106, road connection states and attributes of each road (types such as highways and ordinary roads) are recorded as road network data. The state of road connection is represented by node data composed of latitude and longitude such as intersections and branch points, and link data representing roads by line segments connecting the node data. When there is a route search request from the mobile phone 200, the route search server 100 uses the route database 106 to search for a recommended route connecting the designated departure place and destination. Then, the recommended route data obtained as a result of the search is transmitted to the mobile phone 200 via the communication unit 102.

  As described above, in this embodiment, the route search server 100 and the map server 150 are configured as separate servers. However, these servers can also be configured as an integrated server.

  As described above, the map display system 10 of this embodiment is a communication type system in which the mobile phone 200 displays a map and the server on the network stores the map database 156 and the route database 106. It was supposed to be. However, the map display system 10 is not necessarily a communication type system, and the map display device itself is stored in its own storage device (hard disk, flash memory, various disk media), the map database 156 and the route database 106. May be stored. In this embodiment, an example in which the mobile phone 200 is applied as a map display device is shown, but the present invention is not limited to this, and a stationary or portable navigation device, a personal computer, a game machine, and various personal digital assistants (PDAs) can be used. Of course, it is applicable as a map display device. Even when these devices are applied as the map display device, the map database 156 and the route database 106 may be stored in a server on the network, or stored in a storage device included in the map display device. It is good as well.

B. Route search process:
FIG. 3 is a flowchart of route search processing executed by the main control unit 210 of the mobile phone 200. This process is a process executed when the user calls the route guidance function of the mobile phone 200 using the command input unit 206.

  When the route search process is started, first, the main control unit 210 receives a command from the user via the command input unit 206 as necessary, such as a departure point, a destination, a waypoint, a search condition, and a moving means to be used. An input such as a type is accepted (step S10). The departure point can be the current position detected by the GPS receiver 201. The search conditions are conditions such as necessity of using VICS (Vehicle Information and Communication System) information, designation of departure time and arrival time, whether to use a sidewalk with stairs or a roof. The moving means to be used is selectively input from a choice of “walking”, “bicycle”, “car”, “train”, etc. displayed on the display panel 202 by a predetermined GUI (graphical user interface). can do. Upon receiving these inputs, the main control unit 210 transmits a route search request signal to the route search server 100 using the wireless communication circuit 205 (step S20). This request signal includes the information input in step S10.

  When the route search server 100 receives a route search request signal from the mobile phone 200, the route search server 100 refers to the route database 106 stored in the storage device 105 and connects the departure point and the destination included in the request signal (via route). If the route is set, a recommended route that satisfies the set search condition is calculated. The recommended route can be calculated using, for example, a well-known Dijkstra method. When the route search server 100 calculates the recommended route, it returns data representing the shape of the route to the mobile phone 200 in the form of a vector as recommended route data. In the recommended route data, information indicating the type of the road is recorded as attribute information for each road constituting the route. The types of roads include types such as general roads and highways.

  When the route database 106 is prepared for each moving means in the storage device 105, the route search server 100 obtains a recommended route using the route database corresponding to the moving means input by the user. In this way, a route suitable for the user's moving means can be guided. Further, when the type of moving means is not input from the user, a recommended route suitable for a default moving means (for example, a vehicle) may be obtained. Further, based on a predetermined table or conditional expression, a moving means corresponding to the distance between the departure place and the destination may be automatically selected, and a recommended route suitable for the moving means may be obtained. For example, if the distance between the departure point and the destination is within 500 m, walk, if it is 500 m to 2 km, walk and vehicle, if it is more than 500 km, if it is more than 500 km, use a vehicle, train, aircraft or ship. The path to be included can be searched. Of course, the user can arbitrarily select the moving means by himself.

  When receiving the recommended route data from the route search server 100 (step S30), the main control unit 210 of the mobile phone 200 stores the recommended route data in the RAM 212 (step S40). The recommended route data stored in the RAM 212 is displayed on the display panel 202 in a map display process described later.

C. Map display processing:
FIG. 4 is a flowchart of the map display process executed subsequent to the route search process shown in FIG. In the present embodiment, it is assumed that the main control unit 210 of the mobile phone 200 executes this process once per second. The execution timing may be changed according to the moving means and moving speed of the user. For example, if the moving means is a vehicle, it can be executed several times per second, and if it is walking, it can be executed about once every few seconds.

  When this map display process is executed, the main control unit 210 first detects the current position using the GPS receiver 201 (step S100). Then, the detected current position is compared with the position of the recommended route stored in the RAM 212, and it is determined whether the current position is detected within a predetermined error tolerance centered on the recommended route (step S110). The error tolerance range refers to a range in which a measurement error by the GPS receiver 201 is allowed and the detected current position can be regarded as a position on the recommended route. For example, the allowable error range may be 200 m in the left-right direction of the recommended route. This allowable error range can be varied according to the moving means and moving speed of the user, or the attribute of the route being traveled (whether it is a highway or a general road). For example, by using a predetermined table and conditional expression, the error allowable range can be set wider as the moving means has a higher speed.

  If the current position is detected within the allowable error range (step S110: Yes), the main control unit 210 corrects the detected current position to the closest position on the recommended route (step S120). Specifically, the main control unit 210 draws a perpendicular line with respect to the recommended route from the detected current position, and corrects the current position to a position where the perpendicular line and the recommended route intersect. Also, the current position may be corrected to the nearest latitude / longitude of the latitude / longitude constituting the recommended route. Note that if the detected current position is a position on the recommended route, the processing in step S120 may be skipped.

  When the current position is corrected, the main control unit 210 acquires map data of a predetermined range (for example, 500 m square) including the corrected current position from the map server 150 (step S130). When map data around the current position is buffered in the RAM 212, the main control unit 210 acquires map data corresponding to the current position from the buffered data. The range of the map data to be acquired can be adjusted according to the map display scale set by the user.

  When the map data is acquired, the main control unit 210 superimposes the recommended route stored in the RAM 212 and the map data in the vector format acquired in step S130 on the display panel 202 (step S140). Further, a mark indicating the current position after correction is drawn thereon. Through the above processing, the corrected current position can be displayed on the map image. The main control unit 210 displays the map by drawing features for each of the same type of detailed attributes and overlaying them in layers.

  In step S110, if the current position detected in step S100 is not detected within the allowable error range (step S110: No), the current position deviates from the recommended path even if measurement error is taken into consideration. Can be estimated. Therefore, the main control unit 210 corrects the current position on the feature represented by the graphic data for drawing the map instead of the recommended route by executing the processing described below. In order to correct the current position to the position on the feature, first, the main control unit 210 corrects the current position according to the type of the moving means of the user input in step S10 of the route search process shown in FIG. The attribute of the feature serving as a reference to be specified is specified (step S150). For specifying the attribute of the feature, the attribute specifying table TBL shown in FIG. 5 is referred to. The attribute specifying table TBL is stored in the ROM 213.

  FIG. 5 is an explanatory diagram showing an example of the attribute identification table TBL. In FIG. 5, for each moving means such as walking, vehicle, train, and ship, information indicating whether or not the feature of each attribute can be a reference for correcting the current position is indicated by “◯” and “×”. It is represented. According to the example of FIG. 5, for example, when the moving means is walking, the feature with the attributes of the water area, the road, and the track cannot be a reference for correction, and the ground with other attributes is attached. Objects can be the basis for correction. Further, when the moving means is a vehicle, a feature with a road attribute can be a reference for correction, but a feature with other attributes cannot be a reference for correction. In addition, when the moving means is a train, only the attribute of the track and the station can be a reference for correction. Further, when the moving means is a ship, only a feature having a water area attribute can be a reference for correction. As described above, the attribute specifying table TBL defines whether or not each moving means can be a reference for correction depending on whether or not each attribute can exist on the feature of each attribute. Yes.

  In step S150, when the main control unit 210 identifies the attribute of the feature serving as a reference for correcting the current position, the latitude / longitude information and attribute information associated with each feature in the map data acquired from the map server 150 are displayed. Based on the above, it is searched whether the feature having the attribute specified in step S150 exists in the vicinity of the current position detected in step S100 (for example, within 100 m around) (step S160). Note that the range of “near” can be varied according to the moving means and moving speed of the user. In this case, the faster the moving means, the wider the range.

  When the feature having the attribute specified in step S150 is present in the vicinity of the current position (step S160: Yes), the main control unit 210 corrects the current position to a predetermined position on the feature. (Step S170). A specific example of such a correction method will be described later. When there are a plurality of corresponding features in the vicinity of the current position, the current position is corrected to a position on the feature closest to the current position. When the current position is corrected, the main control unit 210 performs the processes of step S130 and step S140 to draw a map based on the corrected current position. If there is no corresponding feature in the vicinity of the current position (step S160: No), the map is displayed by executing the processing of step S130 and step S140 without correcting the current position. .

  FIG. 6 is an explanatory diagram showing an example in which a map is drawn on the display panel 202. In the illustrated example, an example in which the current position is displayed on a general road along the river is shown. In this display example, it is assumed that the recommended route exists outside the screen.

  In step S170, when the current position is corrected, the main control unit 210 changes the correction method according to the attribute of the feature serving as a correction reference. For example, when correcting the current position to a position on a feature with a road or sidewalk attribute, the main control unit 210 detects the current position detected in the same manner as correcting the current position on the recommended route. A perpendicular is drawn from the position to the nearest feature with the attribute of road or sidewalk, and the current position is corrected to the position where the feature and the perpendicular intersect. FIG. 7 shows how the current position is corrected to the position on the nearest road in this way.

  When the current position is corrected to a position on a feature to which a building or station attribute is added, the main control unit 210 corrects the current position to the center position of the building or station. It is difficult to receive GPS radio waves in buildings and stations, and the exact position cannot be displayed on the screen. Therefore, if the current position is corrected to the center position of the building or station, it is possible to clearly grasp that the person exists in the building or station. FIG. 8 shows how the current position is corrected at the center position of the building. Of course, it is also possible to display the current position not at the center position but at the measured position.

  When a current position is detected at a position on a feature with a water area or site attribute, the main control unit 210 corrects the detected current position as it is only when the current position detection accuracy is high. Treat as the current position after. The detection accuracy of the current position can be determined according to the number of satellites captured when the current position is measured, for example. In this case, it can be said that the greater the number of acquired satellites, the higher the accuracy. In addition, for example, by acquiring a parameter representing the level of accuracy from the GPS receiver 201, it is possible to determine whether the accuracy is superior or inferior.

  In addition, when correcting the current position on a feature marked with “surface” as a figure type, such as a water area or site, only when the current position is detected within the surface multiple times. The current position may be displayed on the feature. This makes it possible to display the current position with high accuracy. In this case, the current position may be corrected at the center of the surface, or the current position may be corrected to the average position of the current positions detected a plurality of times. Further, the current position may be corrected to the position detected with the highest accuracy among the current positions detected a plurality of times. FIG. 9 shows an example in which the current position is detected five times in the site and the current position is corrected to the average position.

  According to the map display system 10 of the present embodiment described above, even if the current position deviates from the recommended route, the current position is displayed on the feature represented by the graphic data for drawing the map. Can be corrected. As a result, even if the mobile phone 200 does not have the route database 106, the current position can be accurately displayed on the screen.

  Further, in this embodiment, the attribute of the feature serving as a reference for correcting the current position is specified according to the type of the moving means of the user. Therefore, it is possible to suppress the current position from being displayed on the feature where the user cannot exist.

D. Variations:
As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention is not limited to such an Example, and can take a various structure in the range which does not deviate from the meaning. For example, the map data and the recommended route data are vector format data, but may be raster format data. In addition, the following modifications are possible.

(Modification 1):
In step S170 of the map display process shown in FIG. 4, the main control unit 210 corrects the current position to a position on the feature according to the positional relationship of the plurality of features. Can be limited. Specifically, as shown in FIG. 6, consider a case where there are two roads across one river. At this time, when the user's moving means is a vehicle and the current position is detected near the river, the current position is corrected to a position on one road. Thus, once the current position is corrected to a position on one road, the main control unit 210 limits the correction of the current position to the other road across the river. By doing so, it is possible to prevent the current position from being corrected over two roads. Such a restriction is not limited to the example of two roads and rivers. For example, when the moving means is walking, there are two sidewalks across the expressway, or the moving means is a ship. In some cases, the same can be done when there are two rivers across the land. In addition, based on the update status of the current position detected multiple times, if it is determined that the feature that initially displayed the current position was clearly incorrect, the display target of the current position is changed to another feature This may be allowed.

(Modification 2):
In the above-described embodiment, the attribute of the feature serving as a reference for correcting the current position is specified based on the attribute specifying table TBL. The specification of the attribute of the feature serving as a reference for correction is not limited to the attribute specification table TBL, and can be performed by other methods. For example, the main control unit 210 obtains the average moving speed of the user based on the update status of the current position that is sequentially detected. If the average moving speed is about the speed of walking or bicycle (for example, up to 10 km / h), the attribute of the highway and the general road is excluded, and the feature with the attribute of the sidewalk is used as a reference for correction. It can be. On the other hand, if the average moving speed exceeds 10 km / h, it is possible to exclude the attribute of the sidewalk and specify a general road as a correction reference. In addition, once the current position is detected at the station, the attribute of the feature that becomes the reference for the subsequent correction can be a track. This is because there is a high possibility that the user moves by train after entering the station.

(Modification 3):
In the above embodiment, the main control unit 210 determines the type of the user's moving means (step S150 in FIG. 4) used when referring to the attribute specifying table TBL in response to the input from the user (see FIG. 3 step S10). On the other hand, for example, the main control unit 210 may obtain the average speed of the moving means from the update status of the current position that is sequentially detected, and estimate the type of the moving means of the user according to the average speed. Good. For example, if the average speed is 10 km / h or more, it can be estimated as “car”, if it is less than 10 km / h, “walking” or the like.

(Modification 4):
In the above embodiment, the current position is corrected for the feature represented by the graphic data only when the current position deviates from the recommended route. On the other hand, the recommended route may be stopped only on the screen, and the current position may be always corrected for the graphic data. Specifically, step S110 and step S120 shown in FIG. 4 are omitted, and when the current position is detected in step S100, the process proceeds to step S150. By doing so, it becomes possible to correct the current position using the graphic data for map drawing regardless of the presence or absence of the recommended route.

(Modification 5):
In the embodiment described above, the attribute information in the map database 156 shown in FIG. 2 is divided in order to draw the same kind of features together. On the other hand, this attribute information may be classified according to whether or not it can be a reference for correction of the current position in relation to the type of moving means of the user.

(Modification 6):
In the above-described embodiment, when the detected current position is displayed on the screen, the current position is corrected to the position on the recommended route or the position represented by the graphic data, and then displayed. . On the other hand, the detected current position itself is not corrected, and the display coordinates when displaying the current position on the screen are adjusted to the position on the recommended route or the position represented by the graphic data. It is good as well.

(Modification 7):
In the embodiment described above, by referring to the attribute specifying table TBL shown in FIG. 5, the cellular phone 200 automatically sets the attribute of the feature serving as a reference for correcting the current position according to the moving means of the user. It was decided to decide. On the other hand, the user may arbitrarily select an attribute. This makes it possible to try on which feature the current position is displayed when the moving means is switched.

It is explanatory drawing which shows schematic structure of a map display system. It is explanatory drawing which shows the data structure of a map database. It is a flowchart of a route search process. It is a flowchart of a map display process. It is explanatory drawing which shows an example of an attribute specific table. It is explanatory drawing which shows the example by which the map was displayed on the display panel. It is explanatory drawing which shows a mode that the present position was correct | amended to the position on a road. It is explanatory drawing which shows a mode that the present position was correct | amended to the center position of a building. It is explanatory drawing which shows the example of correction | amendment of a present position when the present position is detected in the site.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Map display system 100 ... Route search server 102 ... Communication part 104 ... Control part 105 ... Memory | storage device 106 ... Path | route database 150 ... Map server 152 ... Communication part 154 ... Control part 155 ... Memory | storage device 156 ... Map database 200 ... Mobile phone 201 ... GPS receiver 202 ... display panel 203 ... voice output unit 205 ... wireless communication circuit 206 ... command input unit 210 ... main control unit 211 ... CPU
212 ... RAM
213 ... ROM
220 ... Call control unit

Claims (14)

A map display device that displays a current position together with a map,
For a plurality of types of features, a data acquisition unit for acquiring map data in which graphic data representing the position and shape of the features and attribute information representing the types of the features are recorded in association with each other;
A detection unit for sequentially detecting the current position;
A search unit that searches the map data based on the graphic data and the attribute information for a feature that exists in the vicinity of the detected current position and may include the current position;
A map display device comprising: a drawing unit that draws the feature represented by the graphic data and draws a display as a current position at a predetermined position on the searched feature. The map display device according to claim 1,
Furthermore, a discriminating unit for discriminating the type of the moving means of the user is provided,
The map display device, wherein the search unit specifies an attribute of a feature that may include the current position according to the determined type of moving means. The map display device according to claim 2,
The map display device, wherein the determining unit determines the type of the moving means based on the update status of the current position detected sequentially. A map display device according to any one of claims 1 to 3,
The type of feature includes a building,
The drawing unit draws a display as the current position at the center position of the building as the predetermined position when the attribute information associated with the searched feature is the building . A map display device according to any one of claims 1 to 3,
The type of feature includes a site,
The drawing unit draws a display as the current position at the detected current position as the predetermined position when the attribute information associated with the searched feature is the site . A map display device according to any one of claims 1 to 3,
The feature types include roads,
When the attribute information associated with the searched feature is the road, the drawing unit sets the predetermined position from the detected current position to the nearest road that is the searched feature. A map display device that draws a display as the current position at a position where a drawn perpendicular line intersects with the road. A map display device according to any one of claims 1 to 3,
The drawing unit sandwiches graphic data in which the type of the first feature that the user cannot exist is associated as the attribute information in the vicinity of the detected current position, and the attribute information is the attribute information. When there is a plurality of graphic data associated with the type of the second feature that the user can exist, any one of the graphic data associated with the type of the second feature After rendering the display as the current position at the position on the feature represented by the graphic data, the current position is positioned at the position on the feature represented by the other graphic data associated with the type of the second feature. A map display device comprising means for restricting the display of the display as being rendered. A map display device according to any one of claims 1 to 3,
The map display device in which at least two of water, site, building, road, railroad, and station exist as the feature types. A map display device according to any one of claims 1 to 3,
The graphic data is further associated with shape type information indicating whether the feature is represented by a line or a surface,
The said drawing part is a map display apparatus which draws the said feature with a line or a surface according to the said shape classification information. The map display device according to claim 9,
When the shape type information corresponding to the searched feature is a surface, the drawing unit is predetermined on the feature only when the current position is detected a plurality of times on the feature. A map display device that draws the display as the current position at the position of. The map display device according to any one of claims 1 to 10,
The data acquisition unit is a map display device that acquires the map data from a predetermined server by wireless communication. A map display method in which a computer displays a current position together with a map,
For multiple types of features, obtain map data in which graphic data representing the position and shape of the features and attribute information representing the type of the feature are recorded in association with each other,
Detect current position sequentially,
A feature that exists in the vicinity of the detected current position and can include the current position is searched from the map data based on the graphic data and the attribute information,
A map display method for drawing the feature represented by the graphic data and drawing a display as a current position at a predetermined position on the searched feature. A computer program for displaying a current position together with a map,
A data acquisition function for acquiring map data in which graphic data representing the position and shape of the feature and attribute information representing the type of the feature are associated with each other and recorded for a plurality of types of features;
A detection function that sequentially detects the current position;
A search function for searching the map data based on the graphic data and the attribute information for a feature that exists in the vicinity of the detected current position and may include the current position;
A computer program for causing a computer to realize a drawing function of drawing the feature represented by the graphic data and drawing a display as a current position at a predetermined position on the searched feature.   A computer-readable recording medium on which the computer program according to claim 13 is recorded.

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