JPH069080B2 - Vehicle route guidance device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a device mounted on a vehicle for performing route guidance to an occupant.

<< Background of the Invention >> In a vehicle route guidance device, there is a demand for automating the work of setting the shortest route from a departure intersection to a destination intersection.

Conventional EDWARD. F. MOORE "The Shortest P"
"Ath Through a Maze" and "Research Report on Possibility of Introducing Dual Mode Bus System" written by the Research Center for Transportation Economics have some descriptions about shortest route search.

However, the short-circuit route search processing described in these documents is still conceptual only, and the national road, prefectural road, private road,
It cannot be applied as it is to an actual road map in which roads with different degrees of importance such as etc. are mixed, and it has not yet been put to practical use.

<Objective of the Invention> The object of the present invention is to apply from a starting intersection under certain conditions when applied to a concrete road in which roads of different importance such as national roads, prefectural roads, private roads, etc. are mixed. It is an object of the present invention to provide a vehicle route guidance device capable of automatically setting the shortest route to an intersection under the condition of passing through an important road.

<< Configuration of the Invention >> The configuration of the present invention will be described with reference to the first claim correspondence diagram.

In the figure, in the first storage means a, for each intersection,
An intersection type indicating whether or not the important roads intersect with each other and the position coordinates thereof are stored.

The second storage means b stores, for each important intersection, an important intersection adjacent to the important intersection and a section distance up to that point.

The third storage means c stores, for each intersection, the adjacent intersection and the section route up to that point.

The fourth storage means d stores an unimportant intersection string on an important road connecting adjacent important intersections.

Given the position coordinates of the departure point and the destination, the route end intersection selection means e refers to the first storage means a and selects the intersection closest to the departure point and the destination as the departure intersection and the destination intersection, respectively. To do.

The main route end selecting means f refers to the first storage means a based on the selected departure intersection and destination intersection, and refers to the intersection closest to the departure intersection and the destination intersection as the departure important intersection and the destination important intersection, respectively. select.

Based on the selected departure intersection and departure important intersection, the route start end search means g refers to the third storage means c and searches for the shortest route from the departure intersection to the departure important intersection under certain conditions. .

The connection main part search means h is the selected important departure intersection,
Based on the purpose important intersection, refer to the second storage means,
The shortest route from the departure important intersection to the destination important intersection is searched under a certain condition, and the adjacent intersections of the obtained important intersection sequence are interpolated by the unimportant intersection sequence read from the second storage means b. .

The route end portion searching means i uses the selected target important intersection,
Based on the destination intersection, the third storage means c is referred to search for the shortest route from the destination important intersection to the destination intersection under a certain condition.

The partial route combining means j completes the guide route by sequentially connecting the searched route start end parts, main parts and end parts.

<< Description of Embodiments >> First, the hardware configuration of the device of this embodiment is described below.
Description will be given with reference to the drawings.

As shown in the figure, this in-vehicle device mainly includes a control device of a stored program system, which is composed of a CPU 1 mainly composed of a microprocessor, a system ROM 2 storing various control system programs, and a RAM 3 used as a working area or the like. Is configured as.

Then, by causing the CPU 1 to execute various control programs (details will be described later) stored in the system ROM 2, various functions are realized as shown in the general flowchart of FIG.

The current position coordinates (X, Y) and the traveling distance ∫ΔD required during traveling are detected by the distance sensor 4 for each constant distance ΔD traveling.
In response to the interrupt pulse obtained from the CPU 1, the CPU 1 executes the current position calculation process (see FIG. 23), and the unit vector addition process using the vehicle direction θ obtained from the direction sensor 5,
And the unit distance ΔD is simply accumulated.

Video RAM6, C is used to transmit guidance information to the driver.
Mainly RT7, VDT (Visual Display Termina
l) (see FIG. 3).

Various commands to the apparatus are issued by using the input operation unit 8 including a numeric keypad or the like, or a known transparent operation panel 10 mounted on the front surface of the VDT 9 as shown in FIG.

As shown in FIG. 3, when the transparent operation panel 10 is pressed by a fingertip or the like, the CPU 1 causes the operation panel interface 1
It is possible to detect the pressed portion via 1.

The external memory 1 stores various information such as road maps and intersections.
It is performed by 2.

As shown in FIG. 4B, in the external memory 12, blocks (0, 0) to (2, 2) obtained by vertically and horizontally partitioning a reference road map (see FIG. 4A) are provided. Correspondingly,
A plurality of block areas are provided.

Each block area further includes a plurality of intersection Nos. Corresponding to the intersections included in the block. Area (1-8),
It is divided into (9 to 11) and (12 to 18).

Each intersection No. In the area, the X and Y coordinate information area of the intersection, the adjacent intersection No. An area, a route information area to an adjacent intersection, a direction information area to an adjacent intersection, an intersection name information area, a flag area and an inter number area are provided.

In the flag area, there are highway road flags, flyover flags,
Expressway Inter-Flag, Expressway Connection Road-Flag, Intersection Name Present Flag, Expressway Inter Exit Flag,
In addition to the high-speed interchange entrance flag, a flag (important intersection flag) indicating that the road is an important intersection where roads of high importance such as national roads intersect with each other is provided in connection with the present invention.

Further, in the external memory 12, in addition to the information about all the intersections shown in FIG. 4B, as shown in FIG. 4C, some information about only the important intersections where high-importance roads intersect each other. Remembered

That is, this area is divided into areas for each central important intersection, and each area has an adjacent important intersection N.
o. The information, the non-important intersection sequence information sandwiched between the adjacent important intersections, and the journey information to the adjacent important intersections are stored.

As will be apparent with reference to FIGS. 4C and 4D, assuming that the central important intersection is (108), this includes four adjacent important intersections (101), (111), (113),
(104) exists.

Then, between the adjacent important intersections (101, 111, 113, 04) of the central important intersection (108), there are non-important intersection sequences (107), (109, 11), respectively.
0), (112) and (106, 105) exist.

Further, the section distances between the central important intersection (108) and the adjacent important intersections (101, 111, 113, 104) are (7 km, 13 km, 11 km, 14 km), respectively.

The information described above is used for selecting a departure intersection, a destination intersection, route search processing, and guidance display processing (I) to (II), which will be described later.
It is used in case I) (see Fig. 10).

Further, in the external memory 12, in addition to the intersection information described above, various kinds of information related to the present invention are stored as shown in FIGS. 5 to 9.

That is, in the external data ROM 12, as shown in FIG. 5, each area name information storage area, reduced map information storage area corresponding to each area name, enlarged map information storage area corresponding to each Zone of each reduced map, In addition to storing the spot name information included in each enlarged map, a table (see FIG. 6) that stores each other area name and the number of the reduced map in association with each other, each Zone of the reduced map and the number of the enlarged map Table stored in association with each other (see FIG. 7), each Z of the enlarged map
A table (see FIG. 8) for associating and storing one and its center coordinates and a table (see FIG. 9) for associating and storing the name of a destination such as a resort and the point coordinates of the destination are stored. Has been done.

The meaning of each of these pieces of information will be described later in the process of identifying the starting point and the destination.

The description centering on the hardware is completed above, and then the software configuration of the apparatus of this embodiment will be described with reference to the drawings starting from FIG.

As shown in the general flow chart of FIG. 10, the software configuration of the apparatus of this embodiment has a starting point / destination specifying process (step 1001), a starting intersection and a destination intersection selecting process (step 1002), and a route searching process ( Step 1003), guidance display processing I (step 1004), guidance display processing II (step 1005), and guidance display processing II
It is roughly divided into 6 processes consisting of I (step 1006).

Of these processes, the one directly related to the present invention is the process of selecting a departure intersection and a destination intersection (step 100).
2) and route search processing (step 1003),
The other four processes are not directly related.

However, although these five processes have already been filed, they have not been published (for example, Japanese Patent Application No. 59-2204).
81, Japanese Patent Application No. 59-220484, Japanese Patent Application No. 59-2
No. 42435, Japanese Patent Application No. 60-57476, Japanese Patent Application No. 60
-57478, Japanese Patent Application 60-70622, Japanese Patent Application 6
0-70623, August 30, 1985 Patent application etc. ).

Therefore, in the following description, a detailed description will be given in the text regarding the selection process (step 1002) of the departure intersection and the destination intersection and the shortest route search process (step 1003). Instead of attaching flowcharts and various figures and tables specifically described in Chapter, the explanation of the text in the specification shall be kept to the minimum necessary.

(A) Determining Place of Departure / Destination In this process, the screen of VDT 9 is used to interact with the operator to finally identify the place of departure / destination.

That is, a list of area names is displayed on the screen (12th
(See the figure), wait for the transparent operation panel to be pressed, and detect the designated area.

Next, a reduced map of the designated area is displayed (see FIG. 13), the transparent operation panel is pressed, and the designated zone is detected.

Then, an enlarged map of the designated zone is displayed (see FIG. 14), the transparent operation panel is pressed, the final designated area is obtained, and its central coordinates are specified as the starting point or the destination.

In addition, for those who are unfamiliar with geography, a list of spot names is displayed (see FIG. 15), the pressing of the transparent operation panel is waited for, the designated spot name is detected, and the coordinates of the start point,
Recognize as the destination.

The above processing is performed by executing the starting point / destination specifying processing shown in the flowchart of FIG.

The relationship between the pressed area and the reduced map number and the relationship between the pressed area and the enlarged map number are obtained by referring to the tables in FIGS. 6 and 7, and each image information is shown in FIG. The one stored in the data ROM 12 is used as shown in FIG.

Further, the relationship between the pressed part and the center coordinates of each Zone and the relationship between the pressed part and the point coordinates can be obtained by referring to the tables in FIGS. 8 and 9.

(B) Regarding the selection process of the departure intersection and the destination intersection This process includes the departure point coordinates (X _S , Y _S ), the destination coordinates (Xd,
Yd), the XY coordinate information of each intersection shown in FIG. 4 is searched, and as shown in FIG. 17, the registered intersection which is in the direction of the destination as viewed from the departure place and is closest to the departure place. Is selected as the departure intersection and the registered intersection closest to the destination is selected as the destination intersection, as shown in FIG.

This is performed by executing the selection process of the departure intersection and the destination intersection shown in the flowchart of FIG.

(C) Regarding Route Selection Process FIG. 19A shows an overall outline of the shortest route search process.

As shown in the figure, this processing is the selection processing of the starting important intersection and the target important intersection (the end of the main route) (step 1910).
0), route main part search process (step 19200), route start part search process (step 19300), route end part search process (step 19400), and partial route combination process (step 19500). It

FIG. 19B shows details of the selection process of the departure important intersection and the destination important intersection.

When this process is started, first, the departure crossing of FIG.
Departure intersection coordinates (X
ss, Yss) and destination intersection coordinates (Xdd, Ydd)
Is read (step 19101).

Then, it is determined whether or not the read departure intersection is an important intersection based on the important intersection flag shown in FIG. 4B.

Here, when the departure intersection is determined to be an important intersection (Yes in step 19102), the departure intersection (Xss, Yss)
Is stored as it is as the starting important intersection (Xks, Yks) (step 19103).

On the other hand, when it is determined that the departure intersection is not the important intersection (No at step 19102), X satisfying the following expression is satisfied.
The Y area is obtained (step 19104).

(X-Xss) (Xdd-Xss) + (Y-Yss) (Ydd-Yss)> 0 The region determined by this formula is a region shown by hatching in FIG. 19C, that is, the starting intersection ( Xss, Ys
It corresponds to the area on the side of the target intersection with a straight line that is orthogonal to the straight line connecting s) and the target intersection (Xdd, Ydd) and that passes through the departure intersection (Xss, Yss) as a boundary.

Next, the coordinates of the important intersection existing in the obtained XY region are referred to, and the intersection closest to the departure intersection is selected from them (step 19105).

Next, departing from the selected important intersection, the important intersection (Xk
s, Yks) (step 19106).

Similarly, it is determined whether or not the target intersection is also an important intersection (step 19107).

If the target intersection is determined to be an important intersection (Yes at Step 19107), the target intersection (Xdd, Ydd)
Is stored as the target important intersection (Xkd, Ykd) (step 19108).

On the other hand, when it is determined that the target intersection is not the important intersection (No at step 19107), X satisfying the following expression is satisfied.
The Y area is obtained (step 19109).

(X-Xdd) (Xss-Xdd) + (Y-Yd) (Yss-Ydd)> 0 The region determined by the above equation is a region shown by diagonal lines in FIG. 19D, that is, the target intersection ( Xdd, Yd
It corresponds to the area on the side of the departure intersection (Xss, Yss) with a straight line orthogonal to the straight line connecting d) and the departure intersection (Xss, Yss) and passing through the target intersection (Xdd, Ydd) as a boundary.

Next, from the important intersections existing in the obtained XY region, the one closest to the departure intersection is selected (step 19110).

Then, the selected important intersection is set to the target important intersection (Xk
d, Ykd).

As a result, as shown in FIG. 19C, the important intersection on the side of the destination intersection as viewed from the departure intersection is selected as the departure important intersection (Xks, Yks), and as shown in FIG. 19D, from the destination intersection. The nearest important intersection on the side of the departure intersection is the target important intersection (Xkd, Yk
d) is selected.

Next, details of the route main part search processing are shown in FIG. 19E.

In this figure, when this process starts, all important intersections next to the departure important intersection (primary important intersection)
Is searched with reference to the stored information shown in FIG. 4C (step 19201).

Next, as shown in FIG. 19F, the journey from the departure important intersection is stored in the journey storage area corresponding to each important intersection (step 19202).

After that, the value of the intersection counter N is updated from the initial value 1 by 1 (step 19203) +1 by 1 (step 192).
10) Search for all important intersections next to each Nth important intersection, that is, the (N + 1) th important intersection (step 19204), and obtain the route from the departure important intersection to each (N + 1) th important intersection. (Step 1920
5).

Then, if the route is not yet stored in the route storage area of the N + 1st-order important intersection (No in step 19206), the route from the departure important intersection is stored in the route storage area corresponding to each intersection (step 19208), and the other. If the journey has already been stored (Yes at Step 19206), the journey is rewritten only when it is shorter than the already stored journey (Step 19207).

While repeating the above, in the (N + 1) th important intersection,
When the target important intersection is found (Yes at Step 19209), the important transits on the way of the shortest route from the target important intersection to the starting important intersection are sequentially stored by relying on the route information to each important intersection (Fig. 19G). reference).

Next, the interpolation processing between important intersections is executed (step 19212).

Details of the interpolation processing between important intersections are shown in FIG. 19H.

In this process, first, the value of the passage order counter I is reset to zero (step 19213), and then the value of I is updated by +1 (step 19214), so that the I-th important intersection and the (I + 1) -th important intersection are The non-important intersection sequence existing between them is read with reference to the stored information shown in FIG. 4C (step 19215), and the read non-important intersection sequence is read as the I-th important intersection and the (I + 1) -th important intersection. And (step 19216).

Then, the above processing is repeated until the value of the passage order counter I reaches the maximum value Imax (step 19).
217).

Now, as shown in FIG. 190, the departure important intersection P
There are 6 intersections (P ₃ , P ₄ , P ₅ , P ₆ , P ₇ , P ₈ ) between ₂ and the target important intersection P _9, and only P ₅ and P ₇ are important among them. Assume that it is an intersection.

In this case, at the time when the processing of step 19211 in FIG. 19E ends, as shown in FIG. 19I,
The important intersection sequence P ₂ → P ₅ → P ₇ → P ₉ is registered.

On the other hand, when the inter-important-intersection interpolation processing shown in FIG. 19H is completed, as shown in FIG. 19J, the non-important intersections P ₃ and P ₄ are provided between the important intersections P ₂ and P _5.
Is also interpolated, and similarly between the important intersections P ₅ and P ₇ ,
The non-important intersection P ₆ is interpolated, and the non-important intersection P ₈ is interpolated between the important intersections P ₇ and P ₉ .

As a result, when the processing of FIG. 19H is completed, the first
As shown in FIG. 9J, a series of intersection lines P ₂ → P ₃ → P ₄ → P ₅ → P ₆ → P ₇ → P ₈ → existing on the important road.
P ₉ will be obtained.

Here, particularly importantly, if without dividing the entire intersection and important intersections and unimportant intersection mix stored simply on the basis of only the critical intersection flag, from the starting key intersection P ₂ until the desired critical intersection P ₉ When the shortest route is searched on the condition that it passes through an important road, the search time becomes extremely large, whereas in this embodiment, the shortest route is first searched only for the important intersections, and then the adjacent important roads are searched. Since a method of interpolating a preset sequence of non-important intersections between the intersections is adopted, the search time is significantly shortened.

Next, details of the route start end search processing are shown in FIG. 19K.

In this process, first, all intersections (primary intersections) adjacent to the departure intersection are searched (step 19301).

Next, the route from the starting intersection is stored in the route storage area corresponding to each intersection in the same manner as in the case of FIG. 19F (step 19302).

Next, the value of the intersection counter N is updated from the initial value 1 (step 19303) by +1 (step 1
9310), all intersections next to each Nth intersection,
Search for the (N + 1) th intersection (step 19304),
Next, the route from the departure intersection to the (N + 1) th intersection is calculated (step 19305).

If the route storage area of the obtained (N + 1) th intersection is not yet stored (step 193).
No, 06), and stores the journey from the departure intersection in the journey storage area corresponding to each intersection (step 19308),
On the other hand, if the route is already stored (step 19306)
Affirmative), the rewriting of the journey is performed only when it is shorter than the previously stored journey (step 19307).

If a departure important intersection is found in the (N + 1) th intersections while repeating the above processing (step 1930).
9) The intermediate transit intersections of the shortest route from the important departure intersection to the departure intersection are stored in order by relying on the travel distance information between the intersections (step 19311).

This will be explained using the example of FIG. 190 described above. In this case, there is no intersection between the departure intersection P ₁ and the departure important intersection P ₂ , but if there are a plurality of intersections, they are The shortest route that connects the two is required.

Next, details of the route end portion search processing are shown in FIG. 19L.

In the figure, when this process is started, first, all the intersections (primary intersections) next to the one of the important important intersections are searched (step 19401), and subsequently, the important objects are stored in the route storage area corresponding to each intersection. The journey from the intersection is stored (step 19402).

Next, the value of the intersection counter N is updated from the initial value 1 (step 19403) +1 (step 1941).
0), all intersections next to each Nth intersection, (N +
1) The next intersection is searched (step 19404), and the route from the target important intersection to each (N + 1) th intersection is obtained (step 19405).

Next, if the route is not yet stored in the calculated route storage area of the (N + 1) th intersection (step 194).
No 06), the route from the target important intersection is stored in the route storage area corresponding to each intersection (step 1940).
8) On the other hand, if the route is already stored (step 19)
Affirmative (406), the rewriting of the journey is performed only when the journey is shorter than the already stored journey (step 19407).

If the target intersection is found in the N + 1th-order intersections while repeating the above (Yes at Step 19409), relying on the information about the route to each intersection, the intermediate transit intersection of the shortest route from the target intersection to the target important intersection Are sequentially stored (step 19411).

This will be described with reference to the example of FIG. 190 described above. Since there is an unimportant intersection P ₁₀ between the objective important intersection P ₉ and the objective intersection P ₁₁ , P ₉ → P ₁₀ → P ₁₁
The intersection row will be finally formed.

Details of the partial path combination processing are shown in FIG. 19M.

When this process is started, as shown in FIG. 19M, the intersection sequence from the departure intersection to the important departure intersection is set in the passage order memory (step 19501).

Next, the intersection sequence from the departure important intersection to the destination important intersection is set in the passage order memory following the departure important intersection (step 19502).

Finally, the intersection sequence from the target important intersection to the target intersection is set in the passage order memory following the target important intersection (step 19503).

When the above process is completed, the vehicle should go from the departure intersection P ₁ to the destination intersection P ₁₁ and pass through the important intersections P ₂ , P ₅ , P ₇ , and P _{9 in accordance} with the route shown in FIG. 190. The guide route is finally completed under the condition (see FIG. 19N).

As described above, according to the above shortest route search processing, the shortest route connecting the departure intersection and the destination intersection is automatically set by giving priority to a route with high traffic importance. Therefore, if route guidance is performed based on this, Generally, it is possible to avoid a prefectural road or a city road, which has a low traffic importance, which is easily lost, and to drive a vehicle along a national road having a high traffic importance, thereby improving the usability of this type of device.

Moreover, when searching for routes, only the important intersections on the shortest route are first searched for, and then the sequence of non-important intersections set in advance is used to interpolate between adjacent important intersections. It is also possible to significantly reduce

In the above embodiment, the distance information of the intersection section is stored in advance on the vehicle side, but instead of this, the required time correlation amount information calculated on the premise of the speed limit of each road, that is, the expressway. Is short and the city road is long,
Alternatively, when the time correlation amount information calculated under the assumption that all roads are driven at the same speed is stored,
By applying the present invention and correcting it with the current traffic flow velocity information, it is possible to always obtain the optimum shortest required time route information.

(D) Guide display process (I) This process is for guiding the travel route from the departure point to the departure intersection. As shown in FIG. 22, until the vehicle approaches within a radius of 300 m from the departure intersection, as shown in FIG. The direction of the departure intersection is displayed using the and arrow-shaped segments, and after approaching within 300 m, the departure route is filled in using the intersection figure with the vehicle traveling direction right above, as shown in FIG. By displaying it, the departure route direction, that is, the route at the intersection is displayed, and at the same time, the traveling locus is drawn on the screen.

This is performed by executing the processes of FIGS. 20, 22, and 24, respectively.

(E) Guide display processing (II) In this processing, while confirming that the current position is not out of the planned traveling route, the approach to the next passing intersection is monitored, and the current position is confirmed each time the arrival at the intersection is confirmed. To fix
The above operation is repeated with the intersection to be passed next as a new target.

In addition, in front of each intersection, Figs. 33, 35, 3
As shown in FIG. 6, the route at the intersection is displayed as a guide using the intersection graphic and the route arrow.

If the intersection to be bent is a grade separation, the 41st
As shown in the figure, the central part of the intersection figure is outlined,
A route arrow is added to this to guide and display the route at the intersection.

Further, while traveling, the traveling locus is always displayed on the road map in a superimposed manner.

This is performed by executing the respective processes shown in the flowcharts of FIGS. 26, 27, 32, 34, 37 and 38.

(F) Guide display process (III) In this process, as shown in FIG. 41, the direction of the destination is displayed by using the car figure and the arrow-shaped segment, and when the destination is approached, Notifies the driver of this with an arrival notification text, as shown in FIG.

This is performed by executing the processing shown in the flowchart of FIG.

<< Effects of the Invention >> As is apparent from the above description of the embodiments, the vehicle route guidance device according to the present invention can be applied to actual roads in which roads of different importance such as national roads, prefectural roads, city roads, etc. Even when applied, the shortest route from the departure intersection to the destination intersection is
It can be set automatically on condition that priority roads are used preferentially, and based on this, accurate route guidance can be provided from the departure intersection to the destination intersection, and route search The time can be shortened, and the usability of this type of device can be significantly improved.

[Brief description of drawings]

1 is a block diagram showing the hardware configuration of the apparatus of this embodiment, and FIG. 3 is a VD.
FIG. 4 is a perspective view showing a state in which a transparent operation panel is attached to T.
FIG. A is an explanatory diagram showing how to divide a road map, FIG. 4B is a memory map showing the contents of memory information for general intersections provided in an external memory, and FIG. 4C is an important intersection provided in the external memory. A memory map showing the contents of dedicated memory information, FIG. 4D is an explanatory view showing the relationship between the information shown in FIG. 4C and a concrete road, and FIG. 5 is provided in an external memory in connection with the present invention. The area name information storage area, the reduced map information storage area, the enlarged map information storage area, the memory map showing the spot name information storage area, FIG. 6 shows a table in which each area name and the number of the reduced map are stored in association with each other. Memory map showing contents, Fig. 7 shows each zone of reduced map
FIG. 8 is a memory map showing the contents of a table that stores the number of the corresponding enlarged map in association with each other. FIG. 8 is a memory map showing the contents of the table that stores each zone of the enlarged map and the center coordinates of the corresponding zone in association with each other FIG. 9 is a memory map showing the contents of a table that stores the relationship between each point name and the corresponding point coordinates in association with each other, FIG. 10 is a general flow chart of the route guidance device, and FIG. 11 is a starting point and a destination. FIG. 12 is a flowchart showing the details of the specific processing, FIG. 12 is an explanatory view showing a state in which area names are collectively displayed on the VDT screen, and FIG. 13 is an explanatory diagram showing a state in which a reduced map is displayed on the VDT screen, FIG. Is an explanatory diagram showing a state in which an enlarged map is displayed on the VDT screen, FIG. 15 is an explanatory diagram showing a state name list displayed on the VDT screen, and FIG. 16 is a departure intersection and a destination intersection. FIG. 17 is a flowchart showing a point selection process, FIG. 17 is an explanatory diagram showing an algorithm for selecting a departure intersection, FIG. 18 is an explanatory diagram showing an algorithm for selecting a destination intersection, and FIG. 19A is a schematic diagram of the entire shortest route search process. Flow chart, FIG. 19B is a flow chart showing details of the selection processing of the departure important intersection and the destination important intersection,
FIG. 19C is a diagram for explaining an algorithm for searching for a starting important intersection, FIG. 19D is a diagram for explaining an algorithm for selecting a target for important intersection searching, FIG. 19E is a flowchart showing details of route main part searching processing, and FIG. 19F. Is a memory map showing the relationship between each intersection number and the route storage area,
FIG. 9G is a memory map showing the relationship between passing order and important intersection numbers, FIG. 19H is a flowchart showing details of interpolation processing between important intersections, and FIG. 19I is the time when the route search processing for only important intersections is completed. 19K is a memory map showing the relationship between the passing order and the intersection number, and FIG. 19J is a memory map showing the relationship between the passing order and the intersection number at the time when the inter-important-interpolation process is completed.
The figure is a flow chart showing the details of the route start end search processing.
FIG. 19L is a flowchart showing details of route end portion search processing, FIG. 19M is a flowchart showing details of partial route joining processing, and FIG. 19N is a relationship between passage order and intersection number in a state where partial route joining processing is completed. 190 is an explanatory diagram showing a specific example of the set route, FIG. 20 is a flowchart showing details of the guidance display process (I), and FIG. 21 is a current position calculation process executed by interruption. 22 is a flowchart showing details of the departure intersection direction display processing, FIG. 3 is an explanatory view showing a display example on the VDT screen on the way from the departure place to the departure intersection, and FIG. 24 is a departure chart. FIG. 25 is a flowchart showing details of road direction display processing, FIG. 25 is an explanatory view showing a display example on the VDT screen when approaching a departure intersection, and FIG.
The figure is a flow chart showing the details of the guidance display process (II).
FIG. 27 is a flow chart showing details of route guidance preparation processing to the next passing intersection, and FIG. 28 is an example of a road map showing the relationship among the test circle A, the test circle B, the error test oval, etc. in the state of heading to the straight ahead intersection. , FIG. 29 is an example of a road map showing the relationship between the test circle B and the error test oval in the state of going to the bent intersection, and FIG. 30 is an explanatory view showing the test area at the time of entering the bent overpass, FIG. Figure is an explanatory view showing the state of each inspection area when exiting a bent overpass, Figure 32 is a flow chart showing the details of route guidance display processing and current position correction processing when passing straight through an intersection, and Figure 33 is approaching a straight intersection Explanatory drawing which shows the display example of the VDT screen at the time of the 3rd,
FIG. 4 is a flow chart showing the details of the route guidance display processing and the current position correction processing when a normal intersection bend has progressed, FIG. 35 is an explanatory view showing a display example of a VDT screen when a bending plane intersection is approaching, and FIG. Explanatory diagram showing a display example of the VDT screen when the vehicle is approaching a bending plane intersection, FIGS. 37 and 38 are flow charts showing details of route guidance display processing and current position correction processing at the time of passing through a normal intersection, and FIG. Is an explanatory diagram showing a display example of a VDT screen when approaching a three-dimensional bend intersection, FIG. 40 is a flowchart showing details of guidance display processing (III), and FIG. 41 is a display example of a VDT screen when approaching a target intersection. FIG. 42 is an explanatory diagram showing a display example of the VDT screen when the destination is approaching. a ... first storage means b ... second storage means c ... third storage means d ... fourth storage means e ... route end intersection selection means f ... main route end intersection selection means g ... route start end search means h ... route main part search means i ... route end part search means j ... partial route connection means

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kazuhiko Yoshida 2 Takara-cho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (56) Reference JP-A-60-202307 (JP, A)

Claims (1)

[Claims] 1. A first storage means for storing, for each intersection, an intersection type indicating whether or not an important road intersects with another important road and its position coordinates, and for each important intersection, an adjacent important Second storage means for storing the intersection and the section distance up to that point, third storage means for storing the intersection and the section distance up to that point for each intersection, and between the adjacent important intersections When the fourth storage means for storing the sequence of unimportant intersections on the important road connecting the points and the position coordinates of the starting point and the destination are given, the starting point and the destination are referred to by referring to the first storing means. Based on the selected departure intersection and destination intersection, route end intersection selection means for selecting the nearest intersection as the departure intersection and the destination intersection, respectively, and referring to the first storage means, the departure intersection and the destination intersection closest to A main path end selecting means for selecting each crosspoint departure critical intersection, the purpose important intersections, selected starting intersection, based on the starting material intersection, third
Based on the selected starting important intersection and destination important intersection, the route starting end search means for searching the shortest route from the departure intersection to the important departure intersection under certain conditions by referring to the storage means of
By referring to the second storage means, the shortest route from the departure important intersection to the destination important intersection is searched for under a certain condition, and the second between the adjacent intersections of the obtained important intersection sequence is searched.
Based on the route main part searching means interpolated by the non-important intersection sequence read out from the storage means, the selected target important intersection, and the target intersection
By referring to the storage means of, the route end part searching means for searching for the shortest route from the target important intersection to the target intersection under a certain condition, and the searched route end part, main part and end part are connected in order. And a partial route connecting means for completing the guide route.