JP6401894B2 - Navigation device - Google Patents

Description

  The present invention relates to a navigation device that guides the travel of a vehicle by setting a travel route to a destination.

  Conventionally, when performing cost calculation in route search processing, the area traffic cost corresponding to each node is calculated using the traffic cost of each link entering this node and the traffic cost of each link exiting from this node. Such an automobile navigation system is known (see, for example, Patent Document 1). Specifically, the area traffic cost is used in consideration of the traffic cost of all links.

Japanese Patent No. 3994938

  By the way, in the automobile navigation system disclosed in Patent Document 1, even if there is a link for which traffic information is not transmitted, a route search is performed using the area congestion cost set in the node at the end point of the link. For this reason, when a vehicle enters a node (intersection) where a link without traffic information and a link with traffic information (congestion or congestion) intersect, a link with no traffic information is more than a link with traffic information. May be preferentially selected. However, when driving a vehicle to a link with no traffic information, that is, a link where the degree of congestion or congestion is unknown, and the link is actually congested or congested, the actual road condition is There is a problem in that route search processing with low accuracy that is not reflected is performed.

  The present invention was created in view of the above points, and an object of the present invention is to provide a navigation apparatus capable of performing a route search process with high accuracy regardless of the presence or absence of traffic information.

  In order to solve the above-described problems, a navigation device according to the present invention includes a destination setting unit that sets a destination, and a map that stores map data including costs as transit times for each of a plurality of links corresponding to a road. Data storage means, traffic information acquisition means for acquiring traffic information sent from outside the vehicle, first cost correction means for correcting the cost of the link associated with the traffic information based on the traffic information, Focusing on each node between adjacent links, a plurality of links exiting from this node are extracted, and the extracted links are associated with the first link to which traffic information is associated. When there is no second link, the link after the correction by the first cost correcting means of the link with the most severe congestion and congestion in the first link The travel route to the destination is searched using the second cost correcting means for correcting the cost of the second link using the strike and the cost after being corrected by the first and second cost correcting means. Route search means.

  Specifically, the first link with the highest degree of congestion and congestion described above is the first link with the highest cost per unit distance among the costs after correction by the first cost correction means. In addition, it is desirable that the second cost correcting unit corrects the cost of the second link using the maximum cost per unit distance.

  If a link with traffic information and a link without traffic information are mixed across a single node, the cost of the link without traffic information is calculated using the cost of the link with traffic information that is most congested and congested. Therefore, it is possible to reflect the surrounding congestion and traffic congestion to some extent, and to perform highly accurate route search processing. Also, since the cost of links without traffic information is corrected to the larger one using the cost of links with the most severe congestion and congestion, there is no traffic information with unknown actual road conditions (degree of congestion and congestion) It is possible to avoid that the link is preferentially selected, and it is possible to prevent a low-precision route search process that does not reflect actual road conditions from being performed.

  Further, when N is a positive value, N times the cost of the second link before correction is set as the first upper limit value, and the cost of the second link by the second cost correcting means is set. The correction is desirably performed within a range not exceeding the first upper limit value. Alternatively, when M is a positive value, M times the cost corrected by the first cost correcting means of the link with the most severe congestion and traffic jam is set as the second upper limit value. The cost correction of the second link by the cost correction means is preferably performed within a range not exceeding the second upper limit value. As a result, it is possible to prevent the cost after the correction of the link without traffic information from becoming too large and the influence of the cost correction by the estimation from becoming excessive.

  Further, when L is a positive value, L times the cost of the second link before correction is set as the lower limit value, and the correction of the cost of the second link by the second cost correction means is as follows: It is desirable to be performed in a range that does not become less than the lower limit. Thus, by reducing the cost of the link without traffic information by correction, it is possible to prevent the vehicle from being preferentially guided to this link.

  In addition, the above-mentioned node enters the other link without straddling the opposite lane from the first link and the first cost when entering the other link across the opposite lane from the one link. The first cost is set to a value larger than the second cost, and the route search means uses the first and second costs corresponding to the nodes. It is desirable to search the travel route. As a result, it is possible to perform a highly accurate route search process taking into consideration the actual time loss when passing through the intersection.

It is a figure which shows the detailed structure of the navigation apparatus of one Embodiment. It is explanatory drawing which shows the cost correction method of the link without traffic information by a cost correction part.

  Hereinafter, a navigation device according to an embodiment to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a diagram illustrating a detailed configuration of a navigation device according to an embodiment. As shown in FIG. 1, the navigation device 100 of this embodiment includes a navigation controller 1, a map data storage device 2, an operation unit 3, a vehicle position detection unit 4, a display device 5, an audio device 6, a beacon transceiver 7, an FM. A multiplex broadcast receiver 8 is included. This navigation device is mounted on a vehicle.

  The navigation controller 1 executes a predetermined operation program using a CPU, a ROM, a RAM, and the like, thereby performing a map image display operation around the vehicle position and a route search process for setting a travel route connecting the departure point and the destination. In addition, various functions such as a route guidance operation for guiding the traveling of the vehicle along the traveling route and a reception operation of traffic information sent from the VICS (registered trademark) center are realized. The detailed configuration of the navigation controller 1 will be described later.

  The map data storage device 2 is a storage medium that stores map data necessary for map display, facility search, route search, and the like and a reading device thereof. The map data storage device 2 stores map data in units of rectangular figure leaves divided into appropriate sizes by longitude and latitude. The map data of each leaf can be specified and read by designating the leaf number.

  The map data includes (1) a drawing unit composed of various data necessary for map display, and (2) a road unit composed of data necessary for various processes such as map matching, route search, and route guidance. (3) An intersection unit composed of detailed data of the intersection is included.

  Further, the drawing unit described above has a background necessary for displaying the VICS conversion layer data necessary for specifying the corresponding road based on the traffic jam information sent from the VICS center and the buildings or rivers. Layer data and character layer data necessary for displaying a city name, a road name, and the like are included.

  In the road unit described above, a line connecting a certain intersection on the road and another adjacent intersection is called a link, and an intersection connecting two or more links is called a node. The road unit includes a connection node table storing detailed data of all nodes and a link table storing detailed data of links specified by two adjacent nodes.

  In the connection node table, for each node, the first cost (calculated by a statistical method) that is the time required to pass this node when entering the other link across the opposite lane from one link Static cost) is associated with the second cost (static cost), which is the time required to pass this node when entering one link from another link without crossing the opposite lane. . Here, the first cost is set to a value larger than the second cost.

  The link table is associated with a cost (static cost) that is the time required for the link to pass for each link.

  The map data storage device 2 is realized by a hard disk device or a semiconductor memory, or by a DVD and its reading device. Further, the map data storage device 2 may be replaced with a communication device (not shown) to acquire map data from an external map distribution server (not shown).

  The operation unit 3 is for receiving user instructions (operations), and includes various operation buttons and operation knobs. In addition, the operation unit 3 includes a touch panel attached to the screen of the display device 5, and an operation instruction can be performed when a user directly points a part on the screen with a finger or the like. Yes. The vehicle position detection unit 4 includes, for example, a GPS receiver, an orientation sensor, a distance sensor, and the like, detects the vehicle position (longitude, latitude) at a predetermined timing, and outputs the detection result.

  The display device 5 is configured by, for example, an LCD (liquid crystal display device), and displays a map image around the vehicle position based on the video signal output from the navigation controller 1. The audio unit 6 outputs a guidance voice or the like generated based on the voice signal input from the navigation controller 1 into the vehicle interior.

  The beacon transmitter / receiver 7 performs two-way communication via radio waves mainly with radio beacons installed on highways, and both with optical beacon transceivers installed mainly on general roads. The traffic information sent from the VICS center is received by performing the direct communication. The FM multiplex broadcast receiver 8 receives traffic information included in multiplexed data superimposed on a general FM broadcast. The traffic information received by the beacon transmitter / receiver 7 and the FM multiplex broadcast receiver 8 includes traffic information indicating how much the specific section on the road is congested, event information indicating an accident or freezing of the road, It includes regulatory information such as face-to-face traffic.

  Next, a detailed configuration of the navigation controller 1 will be described. A navigation controller 1 shown in FIG. 1 includes a map buffer 10, a map readout control unit 12, a map drawing unit 14, a vehicle position calculation unit 20, a facility search unit 30, a destination setting unit 32, a route search processing unit 34, and a route guidance process. Unit 36, VICS information acquisition unit 40, VICS information drawing unit 42, cost correction units 50 and 52, input processing unit 60, and display processing unit 70.

  The map buffer 10 temporarily stores map data read from the map data storage device 2. This map data includes at least data necessary for drawing a map image, data necessary for searching a facility by specifying a search condition, and data necessary for performing route search and route guidance. The map reading control unit 12 sends a map data reading request within a predetermined range in accordance with the vehicle position calculated by the vehicle position calculating unit 20 or the position designated by the user by operating the operation unit 3. Output to. Based on the map data stored in the map buffer 10, the map drawing unit 14 performs drawing processing necessary for displaying a map image on the display device 5 to create map image drawing data.

  The vehicle position calculation unit 20 calculates the vehicle position based on the detection data output from the vehicle position detection unit 4, and if the calculated vehicle position is not on the road of the map data, the vehicle position calculation unit 20 calculates the vehicle position. Perform map matching processing to correct.

  The facility search unit 30 searches for a facility that satisfies the search conditions set using the operation unit 3 based on the map data stored in the map buffer 10. For example, as a search condition, there may be a case where a facility genre is specified and candidate facilities are narrowed down, or a case where a telephone number or an address is specified to narrow down facilities. After a specific facility is extracted in this way, a route search process using this facility as a destination, a display of a map around the facility and detailed information, and the like are performed.

  The destination setting unit 32 sets a destination necessary for the route search processing performed by the route search processing unit 34. For example, a case where a facility extracted by a search by the facility search unit 30 is set as a destination or a point on a map image directly designated by a user by operating the operation unit 3 is set as a destination. It is done.

  The route search processing unit 34 sets a travel route (guidance route) connecting the departure point and the destination (or waypoint) according to a predetermined search condition by route search processing. For example, the vehicle position calculated by the vehicle position calculation unit 20 is set as the departure place. Further, the destination set by the destination setting unit 32 is set as the destination of the route search process. For specific contents of the route search process, various methods such as Dijkstra method and horizontal search method can be used.

  The route guidance processing unit 36 superimposes and displays the guidance route obtained by the route search processing by the route search processing unit 34 on the map, or creates guidance route drawing data for displaying an enlarged view of a right / left turn intersection. At the same time, an audio signal such as intersection guidance necessary to guide the traveling of the vehicle along the guidance route is generated.

  The VICS information acquisition unit 40 performs a process of acquiring traffic information (VICS information) transmitted from the VICS center and received by the beacon transmitter / receiver 7 and the FM multiplex broadcast receiver 8. The traffic information included in the traffic information may include not only the traffic congestion level (the level of traffic congestion and congestion) but also the travel time of the link (the time required for passing) along with the traffic congestion level.

  The VICS information drawing unit 42 performs drawing processing for creating traffic information image drawing data corresponding to traffic jam information, event information, and restriction information included in the traffic information acquired by the VICS information acquisition unit 40. For example, an arrow image as an auxiliary image having a color corresponding to the content (smooth, congestion, traffic jam) of the section specified by the traffic information is drawn, or the location specified by the event information or the regulation information is added to the content A process for drawing a predetermined icon image is performed.

  One cost correction unit 50 corrects the cost of the link associated with the traffic information (congestion information) based on the congestion information. For example, when only the traffic congestion level is included in the traffic congestion information, the cost corresponding to each link is corrected by multiplying the original static cost by a weighting factor corresponding to this traffic congestion level (smooth, congestion, traffic jam). Is done. For example, assuming that the weighting coefficient in the case of “smooth” is set to 1, the weighting coefficient in “congestion” is set to 2, and the weighting coefficient in “congestion” is set to 4, these weighting coefficients corresponding to the contents of the congestion degree Is multiplied by the original static cost. Further, when both the congestion degree and the travel time are included as the traffic jam information, the cost of each link is corrected so that the cost corresponds to the travel time. In addition, the correction method based on the traffic jam information currently performed can be applied as it is for the correction of the cost by the cost correction unit 50.

  The other cost correction unit 52 pays attention to each node between adjacent links, extracts a plurality of links leaving the node, and traffic information (congestion information) corresponds to the extracted links. In the case where the first linked link and the second unlinked link are mixed, the cost correction unit 50 of the link having the highest degree of congestion (degree of congestion or congestion) in the first link. The cost of the second link is corrected using the corrected cost according to (1).

  Specifically, the first link with the highest degree of traffic congestion (degree of congestion, traffic jam) is the first link with the highest cost per unit distance among the costs corrected by the cost correction unit 50. Yes, the cost correcting unit 52 corrects the cost of the second link using the maximum cost per unit distance.

  The input processing unit 60 outputs commands for performing operations corresponding to various operation instructions input from the operation unit 3 toward each unit in the navigation controller 1. The display processing unit 70 receives the map image drawing data created by the map drawing unit 14 and the traffic information image drawing data created by the VICS information drawing unit 42, and overlays the traffic information image on the map image. The image is displayed on the screen of the display device 5.

  The destination setting unit 32 described above is a destination setting unit, the map buffer 10 is a map data storage unit, the VICS information acquisition unit 40 is a traffic information acquisition unit, and the cost correction unit 50 is a first cost correction unit. The correction unit 52 corresponds to the second cost correction unit, and the route search processing unit 34 corresponds to the route search unit.

  FIG. 2 is an explanatory diagram showing a cost correction method for a link without traffic information by the cost correction unit 52. In FIG. 2, N0, N1, and N2 indicate nodes, and L1, L2, L3, and L4 indicate links.

  In FIG. 2, let us consider a case where the cost of the link L4 from the node N1 to the node N2 is corrected.

  Focusing on the node N1 starting from the link L4 and examining the presence or absence of traffic jam information in the exit direction for the four links L1 to L4 exiting from the node N1, the following is obtained.

Link L1: There is traffic jam information (congestion), the link length is 100 m, the cost is 50 s, the cost per unit distance after correction by the cost correction unit 50 is 0.5 (s / m),
Link L2: Traffic information available (smooth)
Link L3: Congestion information present (congested), link length is 200 m, cost is 80 s, cost per unit distance after correction by the cost correction unit 50 is 0.4 (s / m),
Link L4: No traffic jam information, link length 150m.

  The links L1 to L3 described above are the first links with traffic information, and the links L4 are the second links without traffic information. The cost correction unit 52 examines the cost per unit distance of the three links L1 to L3 as the first link, extracts the largest value 0.5 (s / m) among them, and links L4 to this value. Is multiplied by 150 m to correct the cost of the link L4 to 0.5 × 150 = 75 s.

  As described above, in the navigation device 100 of the present embodiment, when a link with traffic information (congestion information) and a link without traffic information are mixed across one node, the degree of congestion and congestion is the most severe. Since the cost of the link without traffic information is corrected using the cost of the link with traffic information, it is possible to reflect the situation of surrounding congestion and traffic congestion to some extent, and to perform highly accurate route search processing. Also, since the cost of links without traffic information is corrected to the larger one using the cost of links with the most severe congestion and congestion, there is no traffic information with unknown actual road conditions (degree of congestion and congestion) It is possible to avoid that the link is preferentially selected, and it is possible to prevent a low-precision route search process that does not reflect actual road conditions from being performed.

  Also, in each node, the first cost when entering the other link across the opposite lane from one link, and entering the other link without straddling the opposite lane from one link The second cost is associated with the first cost, and the first cost is set to a value larger than the second cost, so the accuracy taking into account the actual time loss when passing the intersection Route search processing can be performed.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment (FIG. 2), only the link L4 has no traffic information among the four links L1 to L4 leaving the node N1, and the other three links L1 to L3 have traffic information. However, the present invention can be similarly applied to a case where there are two or more links without traffic information or a single link with traffic information. For example, if there are two or more links without traffic information, the cost of each of these links may be modified to match the cost per unit distance that is the largest among the links with traffic information. In addition, when there is one link with traffic information, the cost per unit distance of this link may be matched.

  In addition, when links without traffic information and links with traffic information are mixed in multiple links exiting from one node, if all traffic information of links with traffic information is “good”, the cost You may make it abbreviate | omit cost correction with respect to the link without the traffic information by the correction part 52. FIG.

  Moreover, you may make it employ | adopt the modification which determines whether the cost correction by the cost correction part 52 is performed according to the magnitude of the cost after correction.

(Modification 1)
When N is a positive value, N times (for example, 10 times) the cost of the second link (link L4 in FIG. 2) before correction by the cost correction unit 52 is set as the first upper limit value. . The cost correction of the second link by the cost correction unit 52 is performed within a range not exceeding the first upper limit value. That is, when the cost of a link without traffic information is corrected, the correction that exceeds N times the static cost before the correction is not performed. If the first upper limit value is exceeded, the cost of the second link is set to this first upper limit value. As a result, it is possible to prevent the cost after the correction of the link without traffic information from becoming too large and the influence of the cost correction by the estimation from becoming excessive.

(Modification 2)
When M is a positive value, M times (for example, 10 times) the cost (80 s) corrected by the cost correcting unit 50 of the link (link L3 in FIG. 2) with the most severe congestion and traffic congestion is the second. Is set as the upper limit. The cost correction of the second link by the cost correction unit 52 is performed within a range not exceeding the second upper limit value. Exceeding the second upper limit is generally difficult to occur, but may occur when the link length of a link without traffic information is extremely longer than other links. When the second upper limit value is exceeded, the cost of the second link is set to the second upper limit value. As a result, it is possible to prevent the cost after the correction of the link without traffic information from becoming too large and the influence of the cost correction by the estimation from becoming excessive.

(Modification 3)
When L is a positive value, L times (for example, 1 time) the cost of the second link before correction (link L4 in FIG. 2) is set as the lower limit value. The cost correction of the second link by the cost correction unit 52 is performed within a range that does not become less than the lower limit value. That is, the cost after correcting the link without traffic information is set so as not to be less than the lower limit value. If the lower limit is not reached, the cost of the second link is set to this lower limit. Thus, by reducing the cost of the link without traffic information by correction, it is possible to prevent the vehicle from being preferentially guided to this link.

  In the embodiment described above, the traffic information sent from the VICS center is received and the cost of the link is corrected. However, information (probe information) indicating road congestion acquired from each vehicle is predetermined. Instead of the traffic information sent from the VICS center, or in parallel, the traffic information of each road (link) created by the aggregation of the server may be used to correct the cost of the link. .

  As described above, according to the present invention, when a link with traffic information and a link without traffic information are mixed across one node, the link with traffic information with the highest degree of congestion and traffic congestion is included. Since the cost of the link without traffic information is corrected using the cost, it is possible to reflect the situation of surrounding congestion and congestion to some extent, and to perform highly accurate route search processing.

DESCRIPTION OF SYMBOLS 1 Navigation controller 2 Map data storage device 4 Vehicle position detection part 7 Beacon transmitter / receiver 8 FM multiplex broadcasting receiver 9 Communication apparatus 10 Map buffer 12 Map reading control part 14 Map drawing part 20 Vehicle position calculation part 30 Facility search part 32 Destination Setting unit 34 Route search processing unit 36 Route guidance processing unit 40 VICS information acquisition unit 42 VICS information drawing unit 50, 52 Cost correction unit 100 Navigation device

Claims (6)

Destination setting means for setting the destination;
Map data storage means for storing map data including costs as transit times for each of a plurality of links corresponding to roads;
Traffic information acquisition means for acquiring traffic information sent from outside the vehicle;
First cost correcting means for correcting the cost of the link associated with the traffic information based on the traffic information;
Focusing on each node between adjacent links, a plurality of links exiting from this node are extracted, and the traffic information is associated with the first link in the extracted plurality of links. When the second link that is not present is mixed, the second link is used by using the cost corrected by the first cost correcting means of the link having the highest degree of congestion and traffic jam in the first link. A second cost correcting means for correcting the cost of the link;
Route search means for searching for a travel route to the destination using the cost corrected by the first and second cost correction means;
A navigation device comprising: In claim 1,
The first link with the highest degree of congestion and traffic jam is the first link having the highest cost per unit distance among the costs after correction by the first cost correction means,
The second cost correcting means corrects the cost of the second link by using the maximum cost per unit distance. In claim 1 or 2,
When N is a positive value, N times the cost of the second link before correction is set as the first upper limit value,
The navigation device according to claim 2, wherein the second cost correction by the second cost correction means is performed within a range not exceeding the first upper limit value. In any one of Claims 1-3,
When M is a positive value, M times the cost after the correction by the first cost correcting means of the link with the most severe congestion and traffic jam is set as the second upper limit value.
The navigation device according to claim 2, wherein the second cost correcting means corrects the cost of the second link within a range not exceeding the second upper limit value. In any one of Claims 1-4,
When L is a positive value, L times the cost of the second link before correction is set as the lower limit,
The navigation device according to claim 2, wherein the cost of the second link is corrected by the second cost correcting means within a range not less than the lower limit value. In any one of Claims 1-5,
In the node, the first cost when entering the other link across the opposite lane from one link, and the first cost when entering the other link without crossing the opposite lane from one link 2 costs are associated, the first cost is set to a value greater than the second cost,
The navigation device characterized in that the route search means searches for a travel route using the first and second costs corresponding to the node.

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