JP2840946B2 - Search display method of recommended route in navigation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Industrial Field of the Invention The present invention relates to a navigation device for searching and displaying a recommended route from a current position to a target position based on input of road information and route selection conditions. How to search and display recommended routes.

Such a navigation device is mounted on an automobile or the like and is used for displaying a road map, a current position, a target position, and the like.

(2) Conventional technology Recently, large-capacity storage devices such as CD-ROMs have been used for navigation devices mounted on automobiles and the like. As such a navigation device, Nikkei Electronics No.434 (Issued November 16, 1987) P119-130
And the like are known.

The navigation device reads necessary road map data from the CD-ROM, displays the data on a CRT display device or the like, and detects the current position using a geomagnetic sensor, a gyro, a vehicle speed sensor, a steering sensor, or the like. it's shown.

In addition, as a system for transmitting traffic information such as traffic congestion status to vehicles, there is a "road-to-vehicle information system" developed by the Ministry of Construction as a joint research project between the public and private sectors. "AMTIC
S ”(Advanced Mobile Traffic Information & Commun
Communication Systems) are known.

Further, as a navigation device for displaying the shortest route, those described in JP-A-55-23535 and those described in JP-A-62-95423 are known.

(3) Problems to be Solved by the Invention However, in a conventional navigation device, a recommended route is searched from a large number of routes from a current position to a target position based on route selection conditions such as a shortest distance. There is a problem that it takes a long time to search, so that even if traffic information such as an accident or traffic congestion is obtained, it is not possible to respond quickly.

The present invention has been made in view of the above-described circumstances, and has as its object to shorten the time required for searching for a recommended route in a navigation device, and to promptly display the route.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 provides a recommended route from a current position to a target position based on input of traffic information and route selection conditions. In a navigation device capable of searching and displaying, and capable of switching a scale of a map on a display screen thereof, a first step of determining a candidate route between a current position and a destination is within a predetermined restriction condition for the candidate route. A second step of searching for a route, and a third step of searching for a recommended route based on the traffic information and the route selection condition from the route searched in the second step, and the third step is performed. The recommended route is displayed based on the search result of the above. In the second stage, the condition range of the route narrowed down by the control condition is set to the size of the scale of the map on the display screen. Change in Flip, characterized by narrowing the range of conditions than when smaller when the scale factor is large.

Further, in the invention of claim 2, in addition to the above feature of the invention of claim 1, the restriction condition includes that the distance is within a predetermined distance range from the candidate route.
The distance range is changed according to the magnitude of the scale of the map on the display screen, and when the scale is large, the distance range is made narrower than when the scale is small. In addition to the above feature of the first aspect of the present invention, the restriction condition includes that a road rank is within a predetermined rank range, and in the second step, the rank range is displayed on a map on a display screen. Change according to the size of the reduction scale,
When the reduced scale is large, only routes having a high rank are searched, and when the reduced scale is small, routes having a low rank are also searched.

Note that, in the present invention, the “scaled scale” is an index indicating the extent to which the distance on the map on the display screen has been reduced from the actual distance (therefore, a scale which is a ratio of the actual distance to the distance on the map). Means that the magnitude relation is reversed), that is, when the scale is small, the map on the display screen is large (ie, the screen is enlarged), and when the scale is large, the map on the display screen is small (ie, the scale is small). Screen).

(2) Operation According to the above feature of the first aspect of the present invention, among a large number of routes from the current position to the target position, a route within a predetermined restriction condition with respect to the candidate route is searched, so that many routes are searched. The search can be performed in a short time even if the search is from. Then, a recommended route is searched based on traffic information such as traffic conditions such as accidents, traffic congestion, and construction, and route selection conditions such as the shortest time, avoiding bad roads, best fuel efficiency, avoiding narrow roads, and selecting snow-removing roads. The search performed in the third stage requires a relatively long time. However, in the third stage, since the route searched in the second stage is set as a search target, the search can be performed in a shorter time than in the case where all routes from the current position to the target position are searched. Therefore, the search target of the recommended route based on the input traffic information and the route selection condition is narrowed down by the predetermined restriction condition, so that the search (and hence the display) of the recommended route can be promptly performed as a whole.

In particular, in the second stage, the condition range of the route narrowed by the restriction condition is changed according to the magnitude of the scale of the map on the display screen, and when the scale is large (when the display screen is a reduced scale). The search time can be shortened by relatively narrowing the condition range, and the search accuracy can be reduced by relatively widening the condition range when the reduced scale is small (when the display screen is an enlarged view). Therefore, priority is given to shortening the search time and improving the search accuracy in accordance with the user's selection of the reduced scale (that is, the intention to roughly or specifically know the route contents) of the user. The degree selection can be made rationally.

According to the second aspect of the present invention, the degree of narrowing down the route to be searched can be easily and accurately changed according to the magnitude of the distance range from the candidate route.

According to the above-mentioned feature of the third aspect of the invention, the degree of narrowing down the route to be searched can be easily and accurately changed depending on the rank of the road.

(3) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, FIG. 1 shows an example of a configuration of a navigation device for performing a method of searching and displaying a recommended route in a navigation device according to the present invention. The processing device 1 includes a microcomputer in which a CPU 11, a ROM 12, a RAM 13, and an input / output interface 14 are connected by a bus 15.

The traffic information receiver 2 is transmitted from the traffic information processing center via a transmitter installed on a road information board, a signal pillar, or the like.
Traffic information and the like are received by the guidance radio system or the quasi-microwave system. The traffic information includes information on the total length of the congested section, the average vehicle speed, the congestion status such as the cause of the congestion, traffic regulation due to accidents and construction, and various warnings. The compact disc player 3 reads data stored on a compact disc, and operates as a read-only external storage device. The compact disk is a so-called CD-ROM in which information useful for driving related to place names, intersection names, famous places, historic sites, public facilities, gas stations, etc. is recorded as data together with road maps. The CRT display 4 performs display based on various data converted into display signals by the processing device 1.
The operation unit 5 includes input devices such as a key switch and a light pen. The self-contained navigation type position sensor unit 6
It is composed of a geomagnetic sensor and a vehicle speed sensor.
The traffic information receiver 2, the compact disc player 3, the CRT display 4, the operation unit 5, and the self-contained navigation type position sensor unit 6 are connected to the input / output interface 14 of the processing device 1.

Next, a processing procedure of the processing apparatus 1 having the above-described configuration will be described with reference to FIG. 2 showing a flowchart and FIGS. 3 to 5 showing screens displayed on the CRT display 4. In the first step S1, traffic information is input from the traffic information receiver 2 and data relating to the current position, the target position, and the display format such as reduction of the road map are input together with the route selection conditions such as the shortest time from the operation unit 5. Is done. Then, based on the input data and the like, necessary information such as a road map is read from the compact disc player 3 and displayed on the CRT display 4.

In the second step S2, it is determined whether or not a candidate route has been input, and if not, the third step S3
Proceed to. The third step S3 corresponds to the first step of the present invention. In this step S3, a suitable candidate route is input by the light pen of the operation unit 5. At this time, the candidate routes are distinguished from each other by, for example, being displayed thicker than other portions, as in a candidate route 30 shown in FIG. 3A. Instead of directly inputting the candidate route 30 by the operation of the operation unit 5, it is also possible to linearly connect the inputted current position and destination to each other to form a candidate route.

Next, the process proceeds to a fourth step S4 corresponding to the second stage of the present invention. In this step S4, a route that is within predetermined restriction conditions for the candidate route 30 is searched. For example, as shown by a chain line in FIG. 3A, the restriction condition is that at least one condition is that the vehicle has an intersection within a certain range from the candidate route 30, and a certain distance from the candidate route 30. May be one of the conditions, and one of the conditions may be to have a certain range of distance with respect to the distance of the candidate route 30. On this occasion,
The search area may be clarified by deleting a portion of the route (shown by a broken line) that is outside the restriction condition, changing the color of the screen, or changing the type of line.

Next, the process proceeds to a fifth step S5 corresponding to the third stage of the present invention. In this step S5, a search is performed from the route searched in the fourth step S4 based on the information such as the traffic information and the route selection condition such as the shortest time. As a result of this search, a route that satisfies the condition is set as a recommended route, a route that satisfies the next condition is set as a next candidate for a recommended route, and so on, and about three types of recommended route candidates are stored.

In a sixth step S6, the recommended route 31 is displayed in the same display form as the candidate route 30, as shown in FIG. 3 (b). At this time, based on the entered traffic information, traffic jam display
32 and additional information 33 such as the cause of traffic congestion and the average vehicle speed are also displayed at the same time. In the next seventh step S7, when the displayed recommended route 31 is not appropriate for another reason or the like, a request for a next candidate is input from the operation unit 5, and it is determined that this input has been made. Return to step S5. And
The route of the next candidate stored in the fifth step S5 is displayed as a recommended route in a sixth step S6. If it is determined in the seventh step S7 that the vehicle has reached the target position based on the input from the self-contained navigation type sensor 6, the operation is terminated. Otherwise, the operation returns to the first step S1 to continue the operation.

Then, in the first step S1, the information of the traffic information receiver 2 is input again, and if there is a change in the condition, the condition to be changed is input from the operation unit 5. At this time, since the candidate route has already been input, the process proceeds from the second step S2 to the eighth step S8. In the eighth step S8, if there is no change in the information input from the traffic information receiver 2 and no input of conditions to be changed from the operation unit 5, the process returns to the first step S1 again.

In the eighth step S8, when there is a change in the information input from the traffic information receiver 2, the information is displayed. For example, when the information is related to the occurrence of an accident, an accident display 42 is displayed as shown in FIG. Further, a current position display 41 on the recommended route 40 is also displayed. Then, the process proceeds to the fifth step S5 to perform a search again. At the sixth step S6, as shown in FIG.
43 is displayed.

The process also proceeds from the eighth step S8 to the fifth step S5 when a condition to be changed is input from the operation unit 5. For example, a recommended route 50 and a condition display 51 are displayed as shown in FIG. At this time, if the condition is changed to the rough road avoidance condition, the search is performed again in a fifth step S5, and a new recommended route 52 as shown in FIG. Displayed with 53.

Further, in this embodiment, when the scale of the map on the screen displayed on the CRT display 4 changes, the restriction condition in the second stage is changed (that is, the condition range of the route narrowed by the restriction condition is displayed on the display screen). The condition range is changed according to the size of the reduced scale of the map above, and when the reduced scale is large, the condition range is made narrower than when the reduced scale is small. For example, when the scale of the map on the display screen shown in FIG. 6A is, for example, 1 / 240,000 and a search is performed within Akm from the candidate route 3, the display screen as shown in FIG. For example, when the scale becomes 1/15000,
The search range may be within Bkm (A <B) from the candidate route 3. In addition, conditions such as the rank of a road, for example, a first-class national highway and a highway, are added to the restriction conditions. When the scale of the map is small, that is, when the map on the display screen is large (in the case of the enlarged screen), the road with a low rank is Is included as a search target, and when the scale of the map is large, that is, when the map on the display screen is small (in the case of the reduced screen), only high-ranked roads such as a first-class national highway and an expressway are used. It may be a search target. In this way, when the scale of reduction is large and the screen is reduced, the route to be searched can be narrowed down as much as possible (for example, roads and the like that are not displayed are excluded from the search target). On the other hand, when the scale is small and the screen is enlarged, the search target route can be widened as much as possible to improve the search accuracy.

As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to the embodiments, and various design changes may be made without departing from the present invention described in the claims. It is possible.

For example, instead of using the light pen for the operation unit 5, it is possible to use a tablet made of a transparent body as described in, for example, JP-A-55-99685.
In addition, a self-contained navigation type sensor unit 6 is used to detect the current position.
However, the accumulated error may be corrected by position information as additional information of the traffic information received by the traffic information receiver 2.

Further, in place of the self-contained navigation sensor unit 6, for example, GPS (Global Position
The receiver of a radio navigation system such as an ing system can also be used.

C. Effects of the Invention As described above, according to the invention of each claim, the first step of determining a candidate route between the current position and the destination, and searching for a route that is within predetermined restriction conditions for the candidate route Since the second stage and the third stage of searching for a recommended route from the routes searched in the second stage based on traffic information and route selection conditions are sequentially performed, the search target of the recommended route is limited. Since it is possible to narrow down the conditions and search for the search target in a short time and search the recommended route as a whole quickly, it is possible to quickly display the recommended route, and also to display traffic information or route selection conditions. Can be quickly changed.

In particular, in the second stage, the condition range of the route narrowed by the restriction condition is changed according to the magnitude of the scale of the map on the display screen, and when the scale is large (in the case of the reduced screen), The search time can be shortened by making the condition range relatively narrow, and when the reduction scale is small (in the case of an enlarged screen), the search accuracy can be improved by making the condition range relatively wide. According to the user's selection of the reduced scale (that is, the intention of roughly or detailedly knowing the contents of the route), it is determined which of the search time reduction and the search accuracy is prioritized. It can be selected automatically reasonably.

According to the invention of claim 2, the restriction condition includes that the distance is within a predetermined distance range from the candidate route. In the second step, the distance range is displayed on a map on a display screen. The distance scale is changed according to the size of the contraction scale, and when the contraction scale is large, the distance range is made narrower than when the contraction scale is small. Can be easily and accurately changed.

According to the invention of claim 3, the restriction condition includes that the road rank is within a predetermined rank range. In the second step, the rank range is displayed on a map on a display screen. Since the scale is changed according to the size of the scale, only the route with the higher rank is searched when the scale is large, and the route with the lower rank is searched when the scale is small. The degree of narrowing down the route to be searched can be easily and accurately changed depending on the rank.

[Brief description of the drawings]

1 to 5 show an embodiment of the present invention. FIG. 1 is a diagram showing an example of the configuration of a navigation device, and FIG. 2 is a diagram for explaining the operation of the navigation device in FIG. Flowchart of FIG. 3, FIG. 4, and FIG.
The figure shows an example of the display screen of the navigation device.
The figure is a diagram showing an example of a display screen for explaining that the search range is changed according to the difference in the scale of the map on the display screen. 30 …… Candidate route, 31,40,43,50,52 …… Recommended route

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-213718 (JP, A) JP-A-62-91811 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G08G 1/0969 G01C 21/00

Claims (3)

(57) [Claims] 1. A navigation device which retrieves and displays a recommended route from a current position to a target position based on input of traffic information and route selection conditions, and is capable of switching a reduced scale of a map on the display screen. A first step of determining a candidate route between the grounds, a second step of searching for a route that is within predetermined restriction conditions for the candidate route, and the traffic information and the traffic information from the route searched in the second step. A third step of searching for a recommended route based on a route selection condition is sequentially performed, and a recommended route is displayed based on a search result of the third step. In the second step, the control condition Is changed according to the magnitude of the scale of the map on the display screen, and when the scale is large, the condition range is narrower than when the scale is small. Serving method recommended route in which the feature that the navigation device to. 2. The restriction condition includes that the distance is within a predetermined distance range from the candidate route. In the second step, the distance range is determined according to the size of a scale of a map on a display screen. 2. The method according to claim 1, wherein the distance range is narrowed when the scale is large compared to when the scale is small. 3. The restriction condition includes that a road rank is within a predetermined rank range, and in the second step,
The rank range is changed according to the magnitude of the scale of the map on the display screen, and when the scale is large, only the route with a high rank is searched, and when the scale is small, the route with a low rank is also searched. The method for searching and displaying a recommended route in the navigation device according to claim 1, wherein the method is a search target.