JP2005321360A - Vehicle-mounted navigation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To permit the search for a more suitable route that is also the route easy of driving. <P>SOLUTION: When the time for turning right is secured at an intersection, in turning the vehicle to the right, a reduced value is set, with respect to the cost of turning right when the time for turning right is not secured. Accordingly, the possibility of performing the search for the route containing the right turn is increased in the route search, and the search for the more suitable route that is also the route easy of driving is permitted. For example, when a right turn arrow signal is installed, the driver can turn to the right, irrespective of an oncoming vehicle. In such an intersection, the reduced cost value of turning right is set. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an in-vehicle navigation device.

  2. Description of the Related Art Conventionally, navigation devices that search for a route connecting two points and perform route guidance according to the searched route are known. This navigation device shows an intersection, and shows a road map having node data to which a passing cost is assigned and road data connecting the intersections to which link data is given. Have data. The passing cost has a left turn cost, a straight travel cost, and a right turn cost. Based on this road map data, when searching for a route connecting two points, a route with a smaller total of passage cost and link cost is searched.

For example, as disclosed in Patent Document 1, when a vehicle turns to the left, it can turn to the left regardless of the oncoming vehicle, so the left turn cost is set lower than the straight travel cost and the right turn cost. Further, when the vehicle turns to the right, it is necessary to sew between the oncoming vehicles and make a right turn. Therefore, the right turn cost is set larger than the left turn cost and equal to or more than the straight traveling cost.
JP 2002-162243 A

  In the conventional apparatus, as described above, the relationship between the magnitudes of the passing costs is expressed by an expression of “left turn cost <straight travel cost ≦ right turn cost”. Thus, since the left turn cost is set to be the smallest, when searching for a route connecting two points, a route that repeats a left turn may be searched. A route searched for only a left turn is generally longer than a route including a right turn.

  The present invention has been made in view of the above-described points, and an object thereof is to provide an in-vehicle navigation device capable of searching for a more appropriate route while being a route that is easy to drive.

In order to achieve the above object, an in-vehicle navigation device according to claim 1 is provided:
A node that indicates a point where a road branches, merges, and intersects, and has node data having a passing cost when passing through the point, and a link data that indicates a road between the points and has a link cost; Road map data comprising:
A route search means for searching for a route connecting two points based on road map data, and for searching for a route so that a sum of a passing cost and a link cost included in the route is reduced,
Route guidance means for performing route guidance as a guidance route between two points, the route searched by the route search means,
The passing cost includes a right turn cost, and the right turn cost is set to a smaller value when the right turn time is secured when the vehicle turns right than when the right turn time is not secured. And

  As described above, in the in-vehicle navigation device according to claim 1, when the right turn time is secured at the intersection when the vehicle turns right, the driver can make a right turn regardless of the oncoming vehicle. The value is reduced with respect to the right turn cost when the right turn time is not secured. This increases the possibility of searching for a route including a right turn in the route search, so that a more appropriate route can be searched for while the route is easy to drive.

  As described in claim 2, it is preferable that the right turn cost is set to a small value when a right turn arrow traffic light is installed at a point corresponding to the node data. When a right turn arrow traffic light is installed, the driver can make a right turn regardless of the oncoming vehicle. For this reason, the possibility of searching for a route including a right turn is increased by setting a reduced value for the right turn cost when the right turn time is not secured.

  As described in claim 3, the right turn cost can be set to a small value when a time difference type intersection is installed at a point corresponding to the node data. When the time difference type intersection is installed, since all the vehicles in the oncoming lane are stopped, the driver can easily turn right. For this reason, compared with the right turn cost when the right turn time is not secured, the possibility of searching for a route including the right turn is increased by reducing the right turn cost.

  As described in claim 4, the passing cost includes the left turn cost, and when the right turn time is secured, it is preferable that the small value at which the right turn cost is set is equal to or less than the left turn cost. As a result, the possibility of searching for a route including a right turn becomes higher than or equal to the possibility of searching for a route that repeats a left turn, and the device can search for a more appropriate route.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a schematic configuration of an in-vehicle navigation device 100 according to the present embodiment. Hereinafter, the in-vehicle navigation device according to the present embodiment will be described in detail.

  As shown in FIG. 1, the in-vehicle navigation device 100 includes a position detector 12 that detects the current position of the vehicle, and a remote controller (not shown) that can input various commands similar to the operation switch 20 for inputting various commands to the device. A remote control sensor 21 for inputting a signal from a control terminal (hereinafter referred to as a remote controller), a map data input unit 22, a display unit 26 for performing various displays such as a map display screen and a TV screen, a speaker 28, and the like described above A navigation control circuit 30 that executes various processes according to inputs from the position detector 12, the operation switch 20, the map data input unit 22, and a remote controller (not shown) and controls the display unit 26 and the speaker 28 is provided.

  The position detector 12 receives a radio wave (GPS signal) from an artificial satellite for a global positioning system (GPS) via a GPS antenna and detects a position, direction, speed, etc. of the vehicle. Are provided with a gyroscope 12b that detects the traveling direction based on the magnitude of the rotational motion applied to the vehicle, and a vehicle speed sensor 12c that includes a vehicle speed sensor, a wheel sensor, and the like for detecting the travel distance of the vehicle. Each of the sensors 12a to 12c has an error of a different property, and is configured to be used while complementing each other. Depending on the accuracy, the sensor may be configured using only a part of the above-described sensors 12a to 12c, or from a geomagnetic sensor for detecting an absolute direction based on geomagnetism, a rotation difference between left and right steering wheels, or the like. You may use the sensor etc. which accumulate | store the steering angle of the vehicle obtained, and obtain | require a direction.

  In addition, as the operation switch 20, a touch switch configured integrally with the display unit 26 and set on the display screen, a mechanical key switch provided around the display unit 26, and the like are used. The touch switch is composed of an infrared sensor arranged indefinitely on the screen of the display unit 26. For example, when the infrared ray is cut off with a finger or a touch pen, the cut-off position becomes a two-dimensional coordinate value (X, X, Y). Thus, a predetermined instruction can be input by directly touching the display screen.

  The operation switches 20 are various switches for operating the vehicle-mounted navigation device 100. Specifically, the operation switches 20 are switches for switching display contents to be displayed on the display unit 26, and a route from the user to the destination. It includes a switch for setting (route).

  On the other hand, the map data input unit 22 is a device for inputting so-called map matching data data for improving the accuracy of position detection and various data including road data representing road connections from a storage medium. As a storage medium, a CD-ROM or a DVD is generally used because of the amount of data, but another medium such as a memory card may be used.

  By the way, the format of the road data includes link data, node data, and link connection information. The link data includes a link ID, which is a unique number for identifying a link, a road type (link class) for identifying, for example, an expressway, a toll road, a general road, or an attachment road, and the width of the road. The road width information indicating the number of lanes or the presence of a median, the start and end coordinates of the link, the road length (link length) indicating the link length, link cost, and the like. On the other hand, the node data includes information such as a node ID that is a unique number of nodes connecting the links, prohibition of turning left and right at intersections, presence / absence of traffic lights, and passing costs.

  The display unit 26 includes, for example, a liquid crystal display panel. On the screen, a mark indicating the current location of the vehicle detected by the position detector 12, road data input from the map data input unit 22, and display on the map Additional data such as guidance routes, names, and landmarks to be displayed can be displayed in an overlapping manner.

  The speaker 28 notifies the user of voice information for various guidance processed by the navigation control circuit 30. The navigation control circuit 30 is configured around a known microcomputer including a CPU, a ROM, and a RAM, and controls the entire apparatus. The navigation control circuit 30 includes a current position calculation unit 31, a destination setting unit 32, a display control unit 33, a guidance control unit 34, a route search unit 35, a calculation parameter table storage unit 36, and a guidance route storage unit 37. .

  The current position calculation unit 31 calculates the current position based on input signals from the GPS receiver 12a, the gyroscope 12b and the vehicle speed sensor 12c, and map data acquired from the storage medium via the map data input unit 22. Since the GPS signal received by the GPS receiver 12a includes time information, the current position calculation unit 31 also outputs current time information.

  The destination setting unit 32 displays a destination setting screen such as a menu screen for setting the destination on the display unit 26 via the display control unit 33 based on an instruction from the operation switch 20 or the remote control sensor 21. To do. When a name, address, telephone number, etc. are input on this destination setting screen, the corresponding facility is set as the destination. The route calculation unit 35 calculates an optimal route from the current location output by the current position calculation unit 31 to the destination. As this route calculation method, a method such as the Dijkstra method is known. The guidance route as the route search result is stored in the guidance route storage unit 37.

  The display control unit 33 highlights the route search result stored in the guide route storage unit 37 over the road data and displays the result on the display unit 26. The guidance control unit 34 detects the current position with respect to the searched route stored in the guidance route storage unit 37 based on the output from the current position calculation unit 31, and performs voice guidance such as the traveling direction of the route by the speaker 28. .

  The route search unit 35 performs a route search using a technique such as the Dijkstra method, and the cost of the entire route is expressed by an equation of cost = total (link cost) + total (passage cost) by this Dijkstra method. The “link cost” is set based on the road length, road width, road type, number of traffic lights, and the like. The “passing cost” includes a left turn cost, a straight travel cost, and a right turn cost.

  Next, the route search process in this embodiment will be described in detail with reference to the flowchart of FIG. FIG. 2 is a flowchart showing a route search processing routine.

  First, in step S10 of FIG. 2, the current position of the vehicle is detected. At this time, the position data by the GPS receiver 12a is acquired in the same form as the coordinate data (latitude and longitude) of the road data described above. Further, data on the traveling direction and travel distance of the host vehicle is acquired by a geomagnetic sensor (not shown), gyroscope 12b, and vehicle speed sensor 12c, and the coordinates of the current position are based on the vehicle position calculated or determined in the past. Calculate data (calculation of coordinate data by self-contained navigation). The current position is basically obtained based on coordinate data calculated by self-contained navigation. However, when the position data by the GPS receiver 12a is acquired, the two are compared, and when the difference is equal to or greater than a predetermined distance, the position data by the GPS receiver 12a is adopted as the current position.

  In step S20, a destination is set. Specifically, for example, a destination setting menu is displayed on the display unit 26. This destination setting menu includes “search by name”, “search by genre”, “search by phone number”, and the like. A destination is set using this destination setting menu.

  In step S30, a route from the current position detected in step S10 to the destination set in step S20 is searched by a technique such as the Dijkstra method. In the route search of this embodiment, cost calculation is performed based on the passage cost and the link cost. Here, the passage cost in the present embodiment will be described with reference to FIG.

  As shown in FIG. 3, the passing cost includes a left turn cost, a straight travel cost, a right turn cost, and depending on the “no traffic light”, “with a traffic light”, or “with a right turn arrow traffic light” at the intersection, A straight traveling cost and a right turn cost are set. First, in the case of “no traffic light”, the passing cost is set as “left turn cost = medium, straight traveling cost = high, right turn cost = high”. For example, when making a left turn at an intersection where there is no traffic light, the driver sets only “left turn cost = medium” because vehicles on one side of the intersection mainly occupy the left turn. On the other hand, when going straight and turning right, vehicles traveling in both lanes become obstacles, so it is necessary to pay close attention to the surrounding traffic conditions in order to go straight and turn right. For this reason, both the straight traveling cost and the right turn cost are set to “large”.

  Next, in the case of “with traffic light”, the passing cost is set as “left turn cost = small, straight traveling cost = small, right turn cost = high”. For example, when the vehicle turns left and goes straight at an intersection with a traffic light, the driver has no obstacle for turning left and going straight, so “left turn cost = small, straight drive cost = small” is set. On the other hand, when making a right turn, the driver sets “right turn cost = high” because the vehicle traveling straight in the opposite lane becomes an obstacle to the right turn.

  Further, in the case of “with right turn arrow signal”, the passing cost is set as “left turn cost = small, straight traveling cost = small, right turn cost = small”. When making a right turn at an intersection with a right turn arrow traffic light, when the right turn arrow is displayed on the traffic light, there is no obstacle to the right turn because the left turn of the oncoming lane and the vehicle that goes straight on are stopped. For this reason, a value reduced with respect to the right turn cost when the right turn time is not secured is set in the right turn cost. As a result, when searching for a route, there is a higher possibility of searching for an appropriate route than including a right turn and repeating a left turn.

  Returning to the flowchart of FIG. 2, in step S40, the route searched in step S30 is displayed. Specifically, the display control unit 33 highlights the searched route on the road data and displays it on the display unit 26. In step S50, route guidance is performed based on the route searched in step S30.

  As described above, according to the present embodiment, when the right turn time is secured at the intersection at the intersection, the value is reduced with respect to the right turn cost when the right turn time is not secured. I did it. Thereby, it is possible to search for a more appropriate route while being a route that is easy to drive.

  Further, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, an example in which a right turn arrow traffic light is installed at a point corresponding to node data has been described. However, the right turn cost may be set to a small value when a time difference type intersection is installed at a point corresponding to the node data. When the time difference type intersection is installed, since all the vehicles in the oncoming lane are stopped, the driver can easily turn right.

  In the above-described embodiment, an example has been described in which a passing cost is set according to the presence / absence of a traffic light and the presence / absence of a right-turn arrow traffic light at a point corresponding to node data included in road map data. However, instead of setting and storing the passage cost in advance, information regarding the presence / absence of a traffic light and the presence / absence of a right turn arrow signal may be acquired and calculated each time a route search is performed. Similarly, the link cost may be calculated based on the road type, the width, the distance, the number of traffic lights, and the like.

  In this way, the degree of freedom regarding what kind of cost is given is improved, the cost is given to give priority to the left turn, and the straight turn priority, the right turn priority when there is a right turn arrow signal, etc. can be freely selected. it can.

  In the above-described embodiment, the example in which the magnitude of the passage cost is divided into three stages has been described. However, the number of divisions of the cost magnitude can be arbitrarily set.

1 is a block diagram showing a schematic configuration of an in-vehicle navigation device 100. FIG. It is a flowchart which shows the routine of the route search process in this embodiment. It is a table | surface which shows the setting value of passage cost in this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Position detector 12a ... GPS receiver 12b ... Gyroscope 12c ... Vehicle speed sensor 20 ... Operation switch 21 ... Remote control sensor 22 ... Map data input part 26 ... Display part 28 ... Speaker 30 ... Navigation control circuit 31 ... Current position calculation part 32 ... Destination setting unit 33 ... Display control unit 34 ... Guidance control unit 35 ... Route search unit 36 ... Calculation parameter table storage unit 37 ... Guide route storage unit

Claims (4)

A node that indicates a point where a road branches, merges, and intersects, and has node data having a passing cost when passing through the point, and a link data that indicates a road between the points and has a link cost; Road map data comprising:
Route search means for searching for a route connecting two points based on the road map data, and for searching for a route so that the sum of the passing cost and the link cost included in the route is reduced. When,
Route guidance means for performing route guidance using the route searched by the route search means as a guidance route between the two points;
The passing cost includes a right turn cost, and the right turn cost is set to a smaller value when a right turn time is secured when a vehicle turns right than when a right turn time is not secured. In-vehicle navigation device characterized.   The in-vehicle navigation device according to claim 1, wherein the right turn cost is set to the small value when a right turn arrow signal is installed at a point corresponding to the node data.   The in-vehicle navigation device according to claim 1, wherein the right turn cost is set to the small value when a time difference type intersection is installed at a point corresponding to the node data.   The said passing cost includes a left turn cost, and when the right turn time is secured, the small value at which the right turn cost is set is equal to or less than the left turn cost. 4. The in-vehicle navigation device according to any one of 3.

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