JP4546514B2 - Navigation device and its required time calculation method - Google Patents

Description

  The present invention relates to a technique for searching for a recommended route to a destination and calculating an estimated required traveling time of the route in a navigation device or the like mounted on an automobile.

  2. Description of the Related Art A technology for searching a recommended route from a set departure point to a destination based on road map data and presenting it to a user as a recommended route in a navigation device mounted on an automobile is known.

  Such a recommended route search is performed, for example, by searching for a route with the lowest cost among possible routes from the starting point to the destination by a technique called Dijkstra method. Yes. Here, as the cost of such a route, the total distance of the route and the required travel time are often used.

  In addition, the estimated required travel time of such a recommended route is, for example, when the recommended route is obtained, for each road in the recommended route, the road length and the type of road (highway, general road, etc.) A value obtained by weighting a value according to the vehicle travel time is calculated as the required travel time of each road.

  In recent years, a traffic information communication system known as VICS (Trademark of the Traffic Information Communication System Center) that conveys traffic information to automobile users by communication has been put into practical use.

  This traffic information communication system can use real-time traffic information in automobiles by transmitting traffic information such as traffic jams and traffic regulations from the center to automobiles by optical beacons, radio wave beacons and FM multiplex broadcasting placed on the road In a conventional navigation device, when traffic regulation information is received from such a traffic information communication system, the contents represented by the traffic regulation information are displayed to the user by text, voice, graphic display on a map, etc. I was telling.

  According to the technique for calculating the estimated travel time of the recommended route, there are the following problems.

  In other words, because the required time for the recommended route is calculated according to fixed parameters such as the length of each road and the type of road, traffic restrictions such as traffic congestion on one part of the recommended route or traffic restrictions such as one-way traffic If it is carried out, the calculated estimated required travel time may differ significantly from the actual required travel time.

  Therefore, an object of the present invention is to calculate an estimated required travel time that is more suitable for the actual traffic state of the recommended route.

In order to solve the above problems, in the present invention, for example,
A navigation device,
Traffic information receiving means for receiving traffic information;
Map data storage means for storing map data;
A recommended route search means for reading out map data from the map data storage means and searching for a recommended route to the destination;
A required time calculating means for calculating a required time of the recommended route,
The required time calculating means includes
M− (M × Y / X) + N
(Here, X is the section length, M is a static required time which is a predetermined required time for the section, and Y is indicated by the traffic information received by the traffic information receiving means in the section. (N is the time required for the traffic jam point indicated by the traffic jam information received by the traffic jam information receiving means)
Dynamic required time calculation means for calculating dynamic required time using
A static required time calculating means for calculating a static required time from a required time corresponding to a predetermined section constituting the recommended route and a weight corresponding to a road type of the predetermined section;
Comparing means for comparing the dynamic required time and the static required time,
When the dynamic required time is less than a predetermined ratio with respect to the static required time, the dynamic required time is used as the required time of the section constituting the recommended route,
When the dynamic required time is a predetermined ratio or more with respect to the static required time, the static required time is used as the required time of the section constituting the recommended route,
Calculate the sum of the required time used in each section as the required time for the recommended route,
A navigation device is provided.

  According to such a route search device, information on traffic jams is taken from a traffic information communication system such as VICS, and the estimated travel time is calculated in consideration of this, so when traffic jams occur or restrictions are being imposed In addition, it is possible to calculate the estimated required travel time more suitable for the actual traffic condition.

  As described above, according to the present invention, it is possible to calculate the estimated required travel time that is more suitable for the actual traffic state of the recommended route.

  Hereinafter, an embodiment of a route search device according to the present invention will be described taking application to an in-vehicle navigation device as an example.

  FIG. 1 shows a configuration of a navigation device according to the present embodiment.

  In the figure, 1 is a processing unit composed of a microprocessor and a memory, 2 is a display device, 3 is a drive unit responsible for accessing a storage medium such as a CD-ROM storing map data, and 4 is a user instruction. An input device 5 for receiving input is a sensor device including a vehicle speed sensor, a direction sensor, a GPS receiver, and the like. Reference numeral 6 denotes a traffic information receiving apparatus for receiving traffic information from the above-described traffic information communication system such as VICS.

  Here, map data recorded on a storage medium such as a CD-ROM mounted on the drive device 3 will be described.

  As shown in FIG. 2, the map data includes road data 21 provided for each road, and the road data 21 includes road information 22 and link information 23.

  The road information 22 includes a road number 26 that uniquely represents the road, a road name 24 that represents the name of the road, a road type 27 that represents the type of the road (toll road, national road, prefectural road), and other road information. Other attributes 25 representing information are included.

  The link information 23 includes link data 28 representing link information provided for each link constituting the road. Here, the link is a line segment that approximates the shape position of the road as a set.

  The link data 28 describes a link number 29 that uniquely represents a link and a required time 30 that is a value proportional to the length of the link. The node information 31 describes node information described below, for example, information that the node corresponds to an expressway interchange, a service area, or an intersection.

  The link data 28 includes, for each of the two nodes at the two ends, a node number 32 uniquely indicating the node, a node coordinate 35 indicating the position of the node, and all of the nodes connected via the link. The adjacent node number list 34 is a list of node numbers of the nodes. Here, the links are always connected at the nodes. For example, in a crossroad, a node is provided at the center, and four links are connected to the node provided at the center. In this case, the node numbers of the four nodes at the other end of the four links connected to the own node are described in the adjacent node number list 34 of the node provided at the center.

  The link data 28 includes link shape information 36 that specifies the shape of the link. The link shape information 36 includes one or a plurality of subnode coordinates 37. When there are two sub-node coordinates 37, the link shape is such that the first node coordinates of the link, the first sub-node coordinates, the second sub-node coordinates, and the second node coordinates of the link are sequentially arranged in this order. It is specified as a shape connected by a straight line.

  Now, in such a configuration, the processing device 1 receives the map data of the mesh to which the traveling direction of the vehicle inputted from the direction sensor of the sensor device 5, the vehicle speed inputted from the vehicle speed sensor, and the measurement current position inputted from the GPS receiver belong. The current position of the vehicle is calculated by reference, or the destination input by the user via the input device 5 and the input from the user via the input device 5 or the input from the sensor device 5 Based on the current position, the recommended route to the destination is calculated.

  Further, the processing device 1 controls the drive device 3 based on the calculated current position, the traveling direction of the vehicle, and the content specified by the user via the input device 5 to read out the map data, A map to be displayed is displayed on the display device 2. The map can be displayed, for example, by displaying a map of the area around the calculated current position at a predetermined scale, displaying a map of an area designated by the user at a predetermined or specified scale, or from the current position. This is done by displaying a map of the area in the range including the destination at an appropriate scale together with the searched recommended route. At this time, a mark representing the current position and traveling direction of the vehicle is superimposed on the map and displayed.

  Hereinafter, the estimated required travel time calculation process performed by the processing device 1 will be described.

  This process is activated and executed periodically or every fixed distance.

  FIG. 3 shows a processing procedure of this estimated required travel time calculation process.

  In this process, first, the link data 28 of the link on the searched recommended route is examined, and a calculation point for calculating the estimated required travel time is selected. As calculation points, nodes that are described as corresponding to intersections, interchanges, and service areas as node information 31 among nodes within a certain range in the travel direction from the current position and the recommended route travel A node that is a point to transfer to a different road is selected (step 301).

  Next, the estimated required travel time to each calculation point is calculated (step 302).

  Calculation of this estimated required time is performed as follows.

  That is, first, for each link on the recommended route from the current position to the destination, the weight corresponding to the road type 27 of the road information 21 of the road data 21 to which the link data belongs at the required time 30 of the link data 28. Is obtained as the static required travel time. At the same time, the link length of each link is obtained from the link data 28.

  Next, a traffic jam start point, a traffic jam end point, and a required time indicated by the traffic jam information received by the traffic information receiving device 6 are captured. Here, the required time indicated by the traffic jam information received by the traffic information receiving device 6 represents the actual travel time between the traffic jam start point and the traffic jam end point indicated by the actual traffic jam information. Then, the dynamic required travel time of each link for which the static required travel time is obtained is obtained by the following equation.

  Dynamic required travel time = M− (M × Y / X) + N Here, as shown in FIG. 4, X is the link length of the link 400, and M is the static required travel obtained for the link 400. Y is the length of the portion 401 included in the link 400 in the section between the congestion start point and the end point, and N is the required travel of the portion 401 obtained from the required time received by the traffic information receiving device 6 It's time.

  However, if the dynamic required travel time obtained by the above equation is longer than a predetermined ratio (for example, twice or more) compared to the static required travel time, there is a possibility that the received information of the traffic information receiving device 6 has an error. Therefore, the static required travel time is used as it is as the dynamic required travel time.

  Next, for each calculated point, the sum of the dynamic required travel times obtained for each link between the current position and the calculated point is obtained, and this is used as the estimated required travel time from the current position to the calculated point. Further, the link length obtained for each link between the current position and the calculated point is set as the travel distance (step 303).

  Next, a value obtained by subtracting the sum of the static required time of each link from the current position to the destination is obtained from the estimated required travel time, and the ratio of this value to the estimated required travel time is calculated as a traffic jam rate (step 304).

  Then, the required travel time to each calculated point is displayed together with the travel distance to each calculated point, for example, as shown in FIG.

  In FIG. 5, the estimated required travel time 502 up to each calculation point is displayed on the left and right of the name 501 of the interchange or intersection or service area indicated by the node information 31 of a node other than the destination selected as the calculation point, arranged in the recommended route The travel distance 503 is displayed. Further, the road between the calculated points is displayed as a line segment 505 connecting the names of the nodes displaying the road, and the corresponding road name 504 is displayed beside the line segment 505. Also, on this line segment 505, a display 506 with the color of the line segment of the approximate position of the traffic jam section specified by the traffic jam end location of the traffic jam start location received by the traffic information receiving device is performed. Further, a mark 510 representing the restriction content indicated by the restriction information received by the traffic information receiving device 6 is displayed in the vicinity of the restriction portion. In the upper part, a bar graph 509 indicating the estimated required travel time 507 to the destination, the travel distance 509, and the traffic congestion ratio is displayed.

  The embodiment of the present invention has been described above.

  In the calculation of the dynamic required travel time described above, if the dynamic required travel time obtained by the above formula is larger than the static required travel time by a predetermined percentage or more, the static required travel time is determined as the dynamic required travel time. Although the travel time is used as it is, the predetermined ratio is based on the regulation information received by the traffic information receiving device 6, and the dynamic required travel time of the section including the traffic jam portion considered to be caused by the regulation is as follows. It may be made larger than other cases. This is because, when there is a traffic jam caused by the regulation, the dynamic travel time may be increased regardless of the reception error of the traffic receiver 6.

  As described above, according to the present embodiment, the estimated required travel time is calculated in consideration of traffic jams and regulations captured from the traffic information communication system, so even when traffic jams occur or regulations are being performed. Thus, it is possible to calculate the estimated required travel time more suitable for the actual traffic state.

  In this embodiment, the processing device 1 may be an electronic computer equipped with a CPU, a memory, and an appropriate OS. In this case, the processing performed by the processing device 1 is performed by the CPU. This is realized by executing the described program. In this case, these programs are supplied to the processing apparatus 1 via a storage medium such as a CD-ROM.

It is a block diagram which shows the structure of the navigation apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the map data which concern on embodiment of this invention. It is a flowchart which shows operation | movement of the navigation apparatus which concerns on embodiment of this invention. It is a figure which shows the way of the dynamic required travel time calculation which concerns on embodiment of this invention. It is a figure which shows the example of a display in the navigation apparatus which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Processing apparatus 2 Display apparatus 3 Drive apparatus 4 Input apparatus 5 Sensor apparatus

Claims (3)

A navigation device,
Traffic information receiving means for receiving traffic information;
Map data storage means for storing map data;
A recommended route search means for reading out map data from the map data storage means and searching for a recommended route to the destination;
A required time calculating means for calculating a required time of the recommended route,
The required time calculating means includes
M− (M × Y / X) + N
(Here, X is the section length, M is a static required time which is a predetermined required time for the section, and Y is indicated by the traffic information received by the traffic information receiving means in the section. (N is the time required for the traffic jam point indicated by the traffic jam information received by the traffic jam information receiving means)
Dynamic required time calculation means for calculating dynamic required time using
A static required time calculating means for calculating a static required time from a required time corresponding to a predetermined section constituting the recommended route and a weight corresponding to a road type of the predetermined section;
Comparing means for comparing the dynamic required time and the static required time,
When the dynamic required time is less than a predetermined ratio with respect to the static required time, the dynamic required time is used as the required time of the section constituting the recommended route,
When the dynamic required time is a predetermined ratio or more with respect to the static required time, the static required time is used as the required time of the section constituting the recommended route,
Calculate the sum of the required time used in each section as the required time for the recommended route,
A navigation device characterized by that. The navigation device according to claim 1,
The navigation apparatus according to claim 1, wherein the predetermined ratio is set to be larger than in other cases when a section constituting the recommended route includes a traffic jam portion caused by a restriction. A method for calculating a required time of a navigation device comprising map data storage means for storing map data ,
A traffic information receiving step for receiving traffic information;
A recommended route search step of reading map data from the map data storage means and searching for a recommended route to the destination;
Performing a required time calculating step of calculating a required time of the recommended route ,
In the required time calculating step,
M− (M × Y / X) + N
(Here, X is the section length, M is a static required time which is a predetermined required time for the section, and Y is indicated by the traffic information received by the traffic information receiving means in the section. (N is the time required for the traffic jam point indicated by the traffic jam information received by the traffic jam information receiving means)
A dynamic time calculation step for calculating a dynamic time using
A static required time calculating step for calculating a static required time from a required time corresponding to a predetermined section constituting the recommended route and a weight corresponding to a road type of the predetermined section;
Performing a comparison step of comparing the dynamic duration and the static duration;
When the dynamic required time is less than a predetermined ratio with respect to the static required time, the dynamic required time is used as the required time of the section constituting the recommended route,
When the dynamic required time is a predetermined ratio or more with respect to the static required time, the static required time is used as the required time of the section constituting the recommended route,
Calculate the sum of the required time used in each section as the required time for the recommended route,
A required time calculation method for a navigation device.

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