JPH01138409A - On-vehicle navigation system - Google Patents

Abstract

PURPOSE:To determine the best route by selecting road segments corresponding to parameters for retrieving a route from a road map storage means and retrieving a combination of road segments for reaching a target destination. CONSTITUTION:When there is no initial setting input (specification of target destination, retrieval parameter, and optimization parameter), a road network where the vehicle travels is displayed 1 and an estimated current position is emphasized and displayed 1. When initial settings are inputted, a retrieval range is limited by a retrieval range limiting device 4 and a route retrieval device 5 reads road segments corresponding to retrieval parameters out of a memory 3 within the limited range to retrieve a route set for reaching the target destination. Then, an optimum route extracting device 6 totalizes road segment data corresponding to the optimization parameter for each route set calculated by the device 5; and the total values are compared with each other to select the smallest value as the best course. Then, an emphasizing device 8 generates a signal for the emphasized display of the best route, and the signal is emphasized and displayed on a display device 1 to guide the vehicle.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an in-vehicle navigation system, and more specifically, it detects the current position based on the cumulative distance and the cumulative direction of travel and detects the current position on the road. This invention relates to an in-vehicle navigation system that displays a route from a current location to a destination as well as a map.

<Prior Art> An in-vehicle navigation system displays the current position of a vehicle on a guidance route to facilitate driving in unfamiliar areas or at night. And recently,
When multiple intersections and roads connecting intersections are digitized and displayed on a screen, and the driver sequentially specifies the intersections displayed on this screen to create a guidance route and guide the vehicle, the above guidance is used. There is an on-vehicle navigation system that displays a route on a screen and, when the vehicle approaches the specified intersection, guides the vehicle by instructing the vehicle in the next direction through voice and screen. 60-200399).

As shown in the block diagram of FIG. 5, the above navigation system includes a road map storage means (1') storing a road network, an intersection designated from the road network, and a designated intersection. Display means (2') for displaying adjacent intersections and road segments connecting the intersections
a designation means (3') for sequentially designating the intersections to be passed among the displayed intersections; and a route storage means (4') for inputting the sequentially designated intersections and storing a route connecting each intersection. , a current position detecting means (5') for detecting the current position of the vehicle based on the changed direction and the changed distance from the time of initial setting, and display means for displaying the route created above, and when approaching the intersection to be passed, the above-mentioned Display switching means (2') for switching the display on the display means (2') to the display of the designated intersection and intersections adjacent to the designated intersection;
6').

To explain in more detail the road map data stored in the road map storage means (1'), as shown in FIG. Page group (Figure 6(a)(b))
(see Figure 6(C)), a block group (see Figure 6(C)) which further divides each of the divided areas into blocks, and an intersection group (see Figure 6(C)) in which the intersections existing in each area of the block are classified by number.
(See Figures (d) and (e)). Furthermore, each of the memory areas of the group of intersections that has been saved has data regarding the number, direction, and distance of each intersection and adjacent intersections stored therein.

When creating a guidance route using the above navigation system, the relevant page, relevant block, and intersection closest to the current location are sequentially designated from the road map stored in the road map storage means (1'), and then the current location is The closest intersection and multiple adjacent intersections are displayed on the screen along with the route, and the driver specifies one of the adjacent intersections displayed on the screen. Then, the adjacent intersection designation operation is repeated until the destination is reached, and a guidance route is created. That is, the above-mentioned - group of intersections are arbitrarily designated by the driver based on data regarding numbers, directions, and distances stored in the road map storage means (1').

When the driver starts the guidance system, the display means (2) displays the estimated current position detected based on the memorized guidance route, the cumulative distance traveled from the initial setting position, and the cumulative direction. ’). When the vehicle approaches the designated intersection, the driver is informed via voice or screen that the vehicle is approaching the designated intersection and the next direction of travel. Switch to the screen showing the intersection.

As described above, a route is created from a uniformly displayed road network based on the data stored in the road map storage means (1'), so those who do not know the details of the surrounding roads they are planning to drive can easily I have no choice but to choose the route depending on my mood. That is, the route is set according to the driver's preference or mood at the time. Moreover, since the intersections are set sequentially along the route, there is a problem that the operation is complicated.

<Object of the Invention> The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide an in-vehicle navigation system that can create an optimal route according to the driver's request.

Means for Solving the Problems> To achieve the above object, the in-vehicle navigation system of the present invention uses a road map that stores a plurality of data regarding a road network and road segments constituting the road network. A storage means, a point specifying means for specifying at least a destination, a parameter setting means for setting parameters for searching a route, and parameters for extracting an optimal route, and corresponding to the parameters for searching the route. a route search means for selecting a road segment from the road map storage means and searching for a combination of road segments that can reach the destination; The present invention includes optimal route extraction means for extracting a route corresponding to an optimal route from among combinations of road segments that can reach a destination.

However, the road segments may be stored in the road map storage means in a hierarchical manner corresponding to expressways, national roads, major local roads, and local roads.

Furthermore, the data regarding the road segment may include at least the road width, distance, and required travel time.

Further, the parameters for searching the route may be those from the road map storage means that allow selection of road segments based on at least road type and road width data.

Furthermore, the parameters for extracting the optimal route may be parameters for extracting the optimal route from the road map storage means based on at least distance data and required travel time data; The optimal route may be extracted based on data obtained by weighting data, required travel time data, and road width data respectively with predetermined weights.

Furthermore, the route search means may calculate the straight-line distance between the current location and the destination, and limit the search range based on this straight-line distance.

Further, it is preferable that the optimum route extracting means calculates the total value of predetermined data of road segments for each searched route, and selects the optimum route by comparing the total values.

Furthermore, it is preferable that the current position is displayed using a map matching method.

In the above-described in-vehicle navigation system, after the driver specifies the destination, sets the parameters for searching for a route, and the parameters for extracting the optimal route, the route search means searches for a route. Road segments are selected from the road map storage means based on the parameters, and a route that can reach the destination from the current location is searched by combining the road segments. and,
Based on the parameters for extracting the optimum route in the route extracting means, predetermined data is selected from a plurality of data regarding road segments stored in the road map storage means, and based on the selected data, The route corresponding to the optimal route is extracted. Then, along with the route corresponding to the extracted optimal route, the current position detected based on the accumulated distance traveled and the accumulated direction can be displayed on the road map to guide the vehicle.

The road segments are expressways, national roads, major local roads,
If the road map is stored hierarchically in the road map storage means corresponding to local roads, routes can be easily limited according to the road type.

Furthermore, if the data regarding the road segment is at least the road width, distance, and required travel time, it is possible to limit the route based on the road width data and also create a route based on the distance and required travel time.

Furthermore, if the parameters for searching a route are at least the road type and road width data stored in the road map storage means, when road segments are selected based on the road type and road width data. Based on this, the search route can be limited. If the parameters for extracting the optimum route are based on at least the distance data stored in the road map storage means and the required travel time data, then the optimum route is extracted based on the distance data. Not only can the shortest distance route be extracted, but also the shortest time route can be extracted based on the required travel time data. Furthermore, if the parameters for extracting the optimal route are based on distance data, required travel time data, and road width data, each with predetermined weights, the optimal route will be more optimal. You can create routes.

Furthermore, if the route search method calculates the straight-line distance between the current location and the destination and limits the search range based on this straight-line distance, the number of combinations of road segments can be limited and unnecessary Route inspection can be omitted.

Furthermore, in the case where the optimal route extraction means calculates the total value of predetermined data of road segments for each searched route and compares the total values with each other, the optimal route is selected. , the same effect as above can be achieved.

Further, when the current position is displayed by map matching, the current position of the vehicle can always be displayed on the route of the road map.

<Embodiments> Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 shows a block diagram of an in-vehicle navigation system according to the present invention. The in-vehicle navigation system includes a display device (1), a point designation key for specifying a destination, a specifying device (2) equipped with parameter setting keys, etc. for setting parameters for route searching (hereinafter referred to as search parameters) and parameters for extracting an optimal route (hereinafter referred to as optimization parameters); , a memory (3) that stores road segments hierarchically according to the road type and stores data (road width, distance, required travel time, etc.) attached to each road segment, and a memory (3) that stores the current location and destination. Calculate the straight line distance between
A search range limiting device (4) that limits the route search range based on this straight-line distance, and a memory (3) that limits the route search range based on the search parameters.
), and searches for a combination of road segments (hereinafter referred to as route set) that will reach the destination from the current location (5).
Then, for each route set above, select predetermined data from the incidental data of the road segment based on the optimization parameters, total the selected data for each route, compare these total values, and optimize the minimum value. An optimal route extraction device (6) that extracts a route, and a current position detection device (6) that calculates the cumulative distance and cumulative direction of travel and detects the estimated n1 current position.
7), an emphasizing device (8) that generates a signal to highlight the optimal route and estimated current position on the road network, and a display (8) that generates a signal to highlight the optimal route and estimated current position on the road network. 1) and a guidance device (9) for guiding the vehicle.

More specifically, the display device (1) has a liquid crystal screen capable of two-dimensional display. In addition, it is also possible to use a CRT, plasma display, EL display, etc. as the display device (1).

FIG. 2 is a diagram explaining the designation device (2
) uses a screen input method, transparent electrodes (not shown) are arranged in a matrix on the screen of the display device (1), and road networks, parameters, parameter coefficients, etc. are displayed in response to key operations. A touch panel (21) that allows you to specify a destination and set parameters by touching a position, and a point specification key (21) that allows you to specify a destination, a planned passage point, etc.
22), a parameter setting key (23) for setting search parameters and optimization parameters, a guidance key (24) for starting guidance of the vehicle, and a cursor key (25). Then, the search parameters can be set by touching the predetermined road type and road width position among the plurality of road types and road widths displayed in response to key (23) operation.
and road width. After setting the search parameters, the optimization parameters will be changed to the displayed distance, required travel time,
By touching a predetermined display position of the mixed parameters, the road segment data used for extracting the optimal route is set. When the above mixed parameters are set, multiple data (distance, required travel time,
A coefficient parameter and a number are displayed to give a predetermined weight to road width data, etc., and a predetermined weight is applied by touching the predetermined coefficient parameter and number position. In addition to the above parameters, parameters that can be specified include:
Based on the data stored in the memory (3), the installation interval of traffic lights, etc. can be specified.

The memory (3) consists of a large capacity memory (3) that stores road maps, and a compact disk ROM, optical hard disk, etc. are used as this memory (3). The storage structure of the memory (3) will be explained in detail with reference to FIG. (See Figures 3(a) and (b)) and a block group obtained by further dividing each divided area into blocks (See Figure 3(e))
, a group of layers classified into road networks, intersections, place names, names, railway transportation networks, building names, etc. in each area of the block (see Figure 3 (d)), and a segment that divides the road network into each intersection. and a road segment group (see Fig. 3 (e)) in which these road segments correspond to four road types: expressways, national roads, major local roads, and local roads.
Furthermore, the distance, direction, and required travel time for each road segment,
It stores incidental data such as road width and average traffic light installation interval (see Figure 3(f)). The above required travel time data is the required travel time calculated statistically based on the past actual travel data of the road segment in the map memory (3), the traffic density observed by the control station, and the average speed data.
It is memorized by day of the week and time of day.

The search range limiting device (4) performs a straight-line distance calculation that calculates the straight-line distance between the current location and the destination based on the estimated current position coordinates from the current position detection device (7) and the touch position coordinates when specifying the destination. (41), and a range setting unit (42) that limits the search range to a rectangular range whose diagonal line is the calculated straight-line distance multiplied by a predetermined number.
It has

The route search device (5) includes a road segment search unit (5) that searches the memory (3) for a road segment of the road type and road width corresponding to the search parameters within the above-mentioned limited range.
1), and a route set search unit (52) that searches for a route set that can reach the destination from the current location.

The optimal route extraction device (6) selects predetermined data from the incidental data of the road segment in the memory (3) based on the optimization parameters for each route set that can reach the destination, and uses the selected data. A first data summation unit (61) that sums up the data, a second data summation unit (62) that sums up the multiplication value of the coefficient parameter and a plurality of data when the mixed parameter is set, and a route selection unit (B3) that compares the total values and selects the minimum value as the optimal route; and a temporary storage unit (64) that temporarily stores the data of the selected route and the road segments that make up the selected route. ).

The current position detection device (7) includes a mileage sensor (71) that detects the mileage from the rotational speed of the wheels, etc., a direction sensor (72) that detects the direction of travel of the vehicle based on geomagnetism, and a direction sensor (72) that detects the traveling direction of the vehicle based on geomagnetism. It has an integrator (73) that integrates the accumulated distance and the accumulated direction, and an estimated current position generator (74) that outputs estimated current position data based on the accumulated data.

The highlighting device B) includes a route highlighting section (8) that generates a signal that highlights the optimal route selected by the route searching device (5).
1), and a current position emphasizing unit (82) that receives current position data from the current position detection device (7) and generates a signal that blinks and displays the estimated current position.

The guidance device (9) displays the road network on which the vehicle is to be traveled in response to a guidance start signal from the guidance start key (24).
The current position highlighting section (82) supplies a signal to the display (1) that blinks the estimated current position, and also supplies a signal to the display (1) that highlights the optimal route generated in accordance with the specified destination. 1).

The operation of the in-vehicle navigation system having the above configuration will be explained.

If there is no initial setting input (designation of destination, search parameters, optimization parameters), the road network you are driving on will be displayed and the estimated current position will be highlighted, and if there is initial setting input The search range limiting device (4) limits the search range based on the straight-line distance between the current location and the destination, and the route search device (5) stores road segments corresponding to the search parameters in the memory (3) within the limited range. )
, and search for a route set that can reach the destination. Next, the optimal route extraction device (6) sums up the road segment data corresponding to the optimization parameters for each route set calculated by the route search device (5), and compares the total values. Select the minimum value as the optimal route. The highlighting device (8) generates a signal to highlight the selected optimal route, and the display (1) highlights the selected route to guide the vehicle.

To explain in more detail, in the specifying device (2), a road network is displayed on the screen in response to a point specifying key operation, and by moving the cursor on the road network and touching the cursor position, you can select a point such as a destination. specify. In this case, it is also possible to zoom in on the touch position and specify the point in more detail. In addition, when inputting a place name, a symbol for specifying the destination etc. is displayed according to the input of the point designation key (22), and by touching the symbol position, the intersection stored in the memory (3) is displayed. Enter the name, etc.

Next, a search parameter is displayed in response to the operation of the parameter setting key (23), and by touching the display position, the road type and road width of the road segment used for route search are set.

After specifying the search parameters, the optimization parameters are displayed, and by touching a predetermined parameter position, the attached data of the road segment used for extracting the optimal route is set.

When a mixture parameter is set in the optimization parameter setting described above, a coefficient parameter and a number are displayed, and the driver touches a predetermined coefficient value to weight the incidental data of the road segment.

When the initial setting operation by the driver is completed as described above, the search range limiting device (4) calculates the straight-line distance between the current location and the destination based on the coordinate positions of the current location and the destination, and calculates the straight-line distance between the current location and the destination. The search range is limited to a rectangular range whose diagonal is the distance multiplied by a predetermined number, and the route search device (
In 5), road segments of the road type and road width corresponding to the search parameters are read from the memory (3) within the above range, and a route set that can reach the destination is searched. next,
In the optimal route extraction device (6), a route set corresponding to the optimal route is selected from the route sets described above according to the optimization parameters. That is, when a distance parameter is specified as an optimization parameter, the first data summation unit (61) sums up the distance data of the road segments that constitute the route set to reach the destination, and calculates the total distance. Compare them and select the shortest route. In addition, even when the required travel time parameter is specified, the first data summation unit (61) calculates the time (monthly , day of the week, and time of day) from the memory (3), calculate the required time for each route set by summing the required time for each road segment, and compare the required times for each route to find the minimum Select a time path. Further, when a mixed parameter and a coefficient parameter coefficient are specified, the second data summation unit (62) calculates the product of the total distance and the distance coefficient for each route set that can reach the destination. , the multiplication value of the total required travel time and the time coefficient, and the multiplication value of the average road width and the road width coefficient are calculated, the multiplication values are summed, and the total values are compared to select the optimal route.

To explain in more detail about the calculation of the total value of the above data, let the above initial setting parameter be X, the number of road segments be j, and F-ΣX ・ ・
The total value of the data is calculated based on the function indicated by mJ.

Then, when the mixing parameter is set, the parameter coefficient is set as G-ΣΣ, x x , ,
The total value of the data is calculated based on the function represented by (I[)1 1J.

That is, assuming that the distance data of each road segment is t for the required travel time data, d for the road width data, and the parameter coefficients are respectively distance coefficient; k, time coefficient: k, and road width coefficient; kd, then the function (I[ ) The total value of the data calculated based on
Shown as a circle. The above total values are compared and the route showing the minimum value is selected as the optimal route. For example, if a distance parameter is specified, the total value of the data is
) is calculated based on the function shown in the formula. That is, the distance data of the road segments stored in the memory (3) are totaled, the total values are compared, and the shortest distance route is selected. In addition, if a time parameter is specified, the required travel time corresponding to the date, day of the week, and time zone for which the destination is specified is read out, the required travel time is totaled, and the total values are compared to calculate the shortest route. calculate. In addition, if multiple parameters are specified, they are calculated based on the function shown in formula (1) above, and the route with the smallest value is selected by comparing the total values (Σ, xJj + Σktxtj + Σkdxdj). .

Next, the highlighting device (8) generates a signal that highlights the selected optimal route, and when the driver operates the guidance key (24), the guidance program starts, and the guidance device (9) generates a signal that highlights the selected optimal route. Display the net (1
), and a signal from the highlighting device (8) that highlights the optimal route and a signal that flashes the estimated current position are supplied to the display (1) to start guiding the vehicle.

Vehicle guidance and optimal route creation procedures will be explained in detail based on the flowchart in FIG. 4.

In step ■, it is determined whether or not a destination has been specified. If it is determined that a destination has not been specified, in step ■, a road map around the current point and the estimated current position are displayed, and the destination is determined. If it is determined that they have been specified, the search parameters and optimization parameters are displayed in step (2), and the user is prompted to set the predetermined parameters. In step ■, it is determined whether or not a mixture parameter has been set. If it is determined that a mixture parameter has not been set, in step ■, road segments corresponding to the search parameters are combined to create a route set that can reach the destination. search for. Next, in step 2, the total value of the data is calculated based on the function (F-ΣX1.) shown by formula (I) according to the optimization parameter Extract the route and perform the following steps.

If it is determined that the mixed parameters have been set in step ■ above, the coefficient parameters are displayed in step ■, the coefficient values are set, and the road segments corresponding to the search parameters are combined in step ■ to reach the destination. Search for possible route sets. Next, in step [phase], the total value of the data is calculated based on the function (G-ΣΣ, Extract the route. In step (2), the optimal route and total data are stored in the temporary storage section (64), and in step (2), the optimal route and total data are displayed. Then, in step [Yes], it is determined whether or not the destination has been reached, and if it is determined that the destination has not been reached,
If the process in step [Yes] is repeated and it is determined that the destination has been reached, step
) and delete the optimal route and total data stored in ), and perform the process of step (2).

In addition, if the search parameters and optimization parameters are not set even after a predetermined period of time has elapsed in step (3) above, the preset default value or the previously set parameters are set as the optimal parameters. It is also possible.

In summary, after the driver sets the destination, search parameters, and optimization parameters, the route search device (5) combines road segments corresponding to the search parameters to create a route set that can reach the destination. The optimal route extracting device (6) selects a route set corresponding to the optimal route from among the route sets described above based on the optimization parameters. Then, the highlighting device (8) generates a signal that highlights the optimal route. Next, in response to the guidance start signal, the guidance device (9) highlights the vehicle's current position on the display (1) along with the optimal route, thereby making it possible to guide the vehicle along the optimal route. That is, an optimal route can be selected based on a plurality of data according to the driver's request, and this optimal route can be displayed to guide the vehicle.

The present invention is not limited to the above-mentioned embodiments. For example, if an in-vehicle navigation system is provided with a receiving function, and sudden information such as an accident is obtained while driving along the above-mentioned guidance route, , it is possible to search for a new optimal route from roads other than the route where the failure occurred, and when data information regarding a new road network is obtained, it can be stored in the memory (3). Furthermore, the optimal route extraction device (6) sequentially compares the total value of each route set searched by the route search means (5), stores the route set with the lowest total value, and stores the route set with the lowest total value. It is possible to select the route set with the lowest total value as the optimal route, and it is also possible to reconfigure only a predetermined section of the optimal route based on other parameters. It is possible to determine whether or not the end point of a segment has been approached, and if it is determined that the end point of the segment is approaching, the road segment to be proceeded next can be displayed blinking or arrowed to indicate the direction of travel, and other points of the invention Various design changes can be made without changing the design.

<Effects of the Invention> As described above, according to the in-vehicle navigation system of the present invention, when the driver specifies a destination,
Parameters for searching a route and parameters for extracting an optimal route are set, and the route search means selects road segments corresponding to the route search parameters from the road map storage means, and combines the road segments. A route that can reach the destination is searched, and the route extraction means extracts a route that corresponds to the optimal route from among the routes that can reach the destination based on the road segment data that corresponds to the parameters for extracting the optimal route. is extracted. In other words, by setting the desired search parameters and optimization parameters, the driver can create a route according to the driver's wishes and display it to guide the vehicle, thereby increasing the efficiency of vehicle operation. This has the unique effect of reducing driver fatigue.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the in-vehicle navigation system of the present invention, Fig. 2 is a front view of the display device and designation device, Fig. 3 is a diagram explaining the storage structure of the memory, and Fig. 4 is a flowchart. , FIG. 5 is a block diagram of a conventional in-vehicle navigation system, and FIG. 6 is a diagram illustrating the storage configuration of a road map storage means of the conventional in-vehicle navigation system. (2...designated device, (3)...memory, (5)...
・Route search device, (6)...optimum route extraction device, (8
)...Emphasis device, (9)...Guidance device (2 idiots)

Claims (9)

[Claims] 1. Total distance traveled and how to accumulate it Road map that detects your current location based on location Display on top as well as destination from current location In-vehicle device that displays the route to the destination In type navigation system, the road Road network and road segments that make up the road network Store multiple data about road map storage means and at least an eye A point specifying means for specifying a destination and a route. Parameters to search, and optimal Set parameters for route extraction parameter setting means and the above route. Path corresponding to the parameters to search Select the road segment from the road map storage means. road segments that can be selected and reach the destination. A route search method that searches for combinations of points. and the parameters for extracting the above optimal route. on the road segment corresponding to the meter. It is possible to reach the above destination based on the data of the combinations of road segments Optimal strategy for extracting routes corresponding to suitable routes and path extraction means. In-vehicle navigation system. 2. Road segment is expressway, national highway, major Hierarchical roads corresponding to local roads and regional roads It is stored in the map storage means. The in-vehicle device according to claim 1 above type navigation system. 3. There is little data on road segments. At least the road width, distance, and required travel time. The in-vehicle device according to claim 1 above type navigation system. 4. There are few parameters for searching routes. At least stored in the road map storage means based on road type and road width data. to select the road segment. The in-vehicle device according to claim 1 above type navigation system. 5. Parameters for extracting the optimal route is stored in at least the road map storage means. Distance data and required travel time The optimal route is extracted based on the Paragraph 1 of the above claims In-vehicle navigation system. 6. Parameters for extracting the optimal route Includes distance data, travel time data and road Each road width data is given a predetermined weight. The optimal route is extracted based on the data obtained. Paragraph 1 of the above claims In-vehicle navigation system described. 7. The route search method is between the current location and the destination Calculate the straight line distance of The above is to limit the search scope. Claims 1 to 6 In-vehicle navigation system described in either stem. 8. The optimal route extraction means of the given data of the road segment for each road. Calculate the total value and compare the total values The above patent that selects the optimal route Any of claims 1 to 7 In-vehicle navigation system described in Kani Mu. 9. Current location display now map matching Claim 1 of the above claims filed by Vehicle-mounted as described in any of paragraphs to paragraphs 8 type navigation system.