JPH0644182B2 - In-vehicle navigation system - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle-mounted navigation device.

BACKGROUND ART Recently, a so-called on-vehicle navigation device has been proposed in which a screen display such as a CRT or a liquid crystal display is installed in a vehicle compartment to display a map screen useful for vehicle operation.

It is desirable for such an in-vehicle navigation device not only to display the designated map screen via the keyboard but also to display the image in such a way as to anticipate the needs of the passenger from the viewpoint of reducing the input operation of the passenger. . That is, the driver may read the time required to reach the destination on the screen himself. Also, when selecting a destination from an unspecified number of destinations, it is necessary for the driver himself to read the required time and the like from the map. Therefore, displaying the current location of the vehicle and the map information including it is not sufficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and an object thereof is to effectively display to a driver when grasping a time required to reach a destination and selecting a destination. It is to provide a vehicle-mounted navigation device that can be used.

In the vehicle-mounted navigation device according to the present invention, the current position detection means for detecting the current position of the vehicle, the vehicle speed sensor for outputting the vehicle speed data, the storage means for storing the map information, and the current position of the vehicle from the storage means are displayed. An in-vehicle navigation device having a search means for searching map information including the calculation means, which calculates a reachable distance of the vehicle within a required time based on the vehicle speed data, and a radius of the reachable distance of the vehicle. Display means for displaying an arc centering on the current position together with the map information retrieved by the retrieval means.

Example Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an in-vehicle navigation device for carrying out the method according to the present invention, in which the display 1 comprises a two-dimensional screen display such as a CRT, a liquid crystal display, etc., for example, in front of a passenger in a vehicle compartment. It is provided in or near the instrument panel provided in. The display 1 is controlled by a display control circuit 2 including, for example, a character generator to display a screen such as a road map. The current position measuring device 3 is, for example, a GPS (Glo
bal Positioning System) and the like, and supplies position data (address) such as longitude and latitude corresponding to the current position of the vehicle to the central processing circuit 4 including, for example, a microprocessor. The input device 5 is, for example, a so-called keyboard, and is used by the passenger to input the scheduled time or the time when the scheduled time has passed and input the restaurant position information or schedule table or memorandum to be displayed at that time or time. It is a means. Information input via the input device 5 is written in the memory circuit 6 by the central processing circuit 4. The storage circuit 6 is composed of, for example, a solid-state memory such as a so-called RAM, and acts as a storage unit that stores a program that defines the operation procedure of the central processing circuit 4 and data to be processed by the central processing circuit 4. The recording medium player 7 is composed of, for example, a so-called CD player, and acts as a storage means for storing a large amount of data although the response is not so good. A tape recording medium such as a so-called VTR may be used as this storage means. Vehicle speed sensor 8
Supplies the vehicle speed data to the central processing circuit 4 every moment, and the central processing circuit 4 sequentially writes in the storage circuit 6.

The current position measuring device in the navigation device is not limited to GPS, and other systems may be used, or the current position may be manually input.

In such a navigation device, the central processing circuit 4 cooperates with the storage circuit 6 and the recording medium player 7 to display various images in response to an operation command from the input device 5. In the present invention, in particular, the central processing circuit 4 executes the operation mode as shown in the plot chart of FIG. That is, in this operation mode, first, a scan command is given to the recording medium player 7 to collect index information pieces associated with the plurality of map screen information pieces recorded on the set recording medium (step S _1). , S ₂ ). The index information pieces include the scale factor of the corresponding map screen information piece and the absolute address (for example, longitude and latitude) of the screen reference position. Then, arithmetic processing is performed on the contents of each index information piece to display the absolute upper limit address [X _H (H), Y _H (N)] and lower limit address [X _H (H), Y _H (N)] of each map screen information piece. X _L (N), Y
_L (N)] is obtained, and this is transferred to the memory circuit 6 as the upper and lower address pairs and written (that is, S ₃ ). Note that N is a natural number and is a number assigned to each map screen information piece. On the other hand, if the current position information obtained from the current position measuring device 3 is not an absolute address to convert it to an absolute address (step S _4). The current street address (X _P , Y _P ) thus obtained is compared with the already obtained X _L (N), X _H (N), Y _L (N), Y _H (N), and X _L (N N) <detecting the X P _{<X H} (N) and _{Y L (N) <Y P} <N which satisfies the formula Y _H (N) (step _{S 4 ', S 5, S} 6).

In this case, it is important that numbers are assigned to the map screen information pieces so that the smaller N is, the smaller the scale factor is, and the search operation is performed in order from the smaller scale factor until the above expression is satisfied. By doing so, the screen information having the smallest scale including the current location is displayed. That is, the central processing circuit 4 instructs the reading of the N-th map screen information pieces with respect to the recording medium player 7 (step S _7). Then, when detecting the predetermined time has passed or the scheduled time has elapsed from a reference time point (Step S _8), an average vehicle speed data obtained from the vehicle speed sensor 8 (Step S _9), by multiplying the predetermined time on the average speed It calculates the distance that may be running within a predetermined time (step S _10). Then, the travel distance in terms of the distance on the screen based on the scale of the map screen information pieces read in S ₇ (step S _11). Next, a circular arc image centered on the current point to the converted distance and the radius (step S _12). Then, the reservation information such as the restaurant position display image or the schedule table which has already been reserved is read (step S ₁₃ ). Naturally, the restaurant position display image data corresponds to the selected Nth map screen. When the reservation information is correlated with the map screen, the screen is formed based on the map, the current location, and the reservation information data (step S
₁₄ , S ₁₅ ). When the reservation information is not related to the map screen like the schedule table, only the reservation information is displayed (steps S ₁₄ and S ₁₆ ).

Note that a modification in which only the information not related to the map such as the schedule table is displayed at the reservation time or when the reservation time has passed is also possible.

EFFECTS OF THE INVENTION As is clear from the above, in the vehicle-mounted navigation device according to the present invention, the reachable distance of the vehicle within the predetermined time is calculated based on the vehicle speed data, and the reachable distance is used as the radius to center the current position of the vehicle. Since the arc to be displayed is displayed together with the corresponding map information, it can be effectively displayed to the driver when grasping the time required to reach the destination and selecting the destination. As a result, the driver can easily perform such grasping and selection and concentrate on driving, which is also preferable from the viewpoint of safety. The display image obtained by the present invention is as shown in FIG. The driver compares the destination with the arc and can see at a glance how much more the vehicle should travel before reaching the destination.

[Brief description of drawings]

FIG. 1 is a block diagram showing an in-vehicle navigation device according to the present invention, FIG. 2 is a flow chart for explaining the operation of the device of FIG. 1, and FIG. 3 is a diagram showing an example of a display screen by the device of FIG. is there. Description of symbols of main parts 1 ... Display device, 2 ... Display control circuit 3 ... Current position measuring device, 4 ... Central control circuit 5 ... Input device, 6 ... Storage circuit 7 ... Recording medium player, 8: Vehicle speed sensor

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Claims (1)

[Claims] 1. A current position detection means for detecting the current position of a vehicle, a vehicle speed sensor for outputting vehicle speed data, a storage means for storing map information, and map information including the current position of the vehicle from the storage means. An in-vehicle navigation device having a searching means for searching, wherein the calculating means calculates a reachable distance of the vehicle within a predetermined time based on the vehicle speed data, and the current position of the vehicle is centered around the reachable distance as a radius. And a display means for displaying the arc of the arrow together with the map information retrieved by the retrieval means.