JPH0339780A - On-vehicle navigation device - Google Patents

Abstract

PURPOSE:To display a past travel track on a display in an easy-to-see state and utilize it for the guidance of a route by reading a position data group which is gathered and stored every time a vehicle travels corresponding to a display speed and supplying it to a display means. CONSTITUTION:While the current position of the vehicle is recognized, the position data group indicating the position coordinates of the current position is gathered and stored in the storage means in order every time the vehicle travels by a constant distance. Then the position data group in the storage means 9 is read out in the storage order at a period corresponding to a preset display speed in response to a display command 21 for the travel track of the vehicle and position data groups centering on the position coordinates based upon the read position data group are read out of storage media 10 - 13 and supplied to the display means. Therefore, while a map in a constant range is displayed in order, the travel track can be displayed. Consequently, the past travel track can be displayed on the display 17 in the easy-to-see state and utilized conveniently to guide the route.

Description

[Detailed description of the invention] Technical field The present invention relates to an on-vehicle navigation device.

BACKGROUND ART In recent years, map data obtained by digitizing each point on a road on a map is stored in a storage medium such as a CD-ROM, and a map of a certain range of area including the current location is created while recognizing the current location of the vehicle. The data group is read from the storage medium and displayed on the display as a map around the vehicle's current location.
In-vehicle navigation devices that automatically display the vehicle's current location on the map are being developed and put into practical use.

When a vehicle is traveling using such an in-vehicle navigation device, the travel trajectory data is stored in the memory, and when necessary, the travel trajectory is displayed on the display based on the stored data, so that the past travel route or This is extremely useful, as it helps you to check the reverse route or the next time you travel the same route.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an in-vehicle navigation device that can display past travel trajectories on a display in an easy-to-see manner and can also be used for route guidance.

In the in-vehicle navigation device according to the present invention, while recognizing the current location of the vehicle, a group of point data indicating the point coordinates of the current location is collected every time the vehicle travels a certain distance and sequentially stored in the storage means. In response to a driving trajectory display command, the memory point data group of the storage means is sequentially read out in the storage order or in the reverse order at a cycle according to a preset display speed, and the point coordinates according to the read point data group are set as the center. By controlling the extraction of the map data group from the storage medium and supplying the extracted map data group and the readout point data group to the display means, a map of a certain range of area centered on the point coordinates according to the readout point data group is displayed. The configuration is such that the travel trajectory is displayed sequentially.

Example Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram showing an embodiment of an in-vehicle navigation device according to the present invention. In the figure, 1 is a direction sensor for detecting the running direction of the vehicle using, for example, geomagnetism (earth's magnetic field), 2 is an angular velocity sensor for detecting the angular velocity of the vehicle, and 3 is a distance sensor for detecting the distance traveled by the vehicle. , 4 is a GPS (Global Position) for detecting the absolute position of the vehicle from latitude and longitude information, etc.
The detection output of each of these sensors (devices) is supplied to the system controller 5.

The system controller 5 connects to an interface 6 which processes the detection outputs of each sensor (device) 1 to 4 manually and processes such as A/D (analog/digital) conversion, and processes various image data and sequentially sends the data from the interface 6. A CPU (Central Processing Circuit) that calculates the vehicle's travel distance, travel direction, current location coordinates (longitude, latitude), etc. based on the output data of each sensor (device) 1 to 4.
7, a ROM (read-only memory) 8 in which various processing programs and other necessary information for the CPU 7 are written in advance, and a RAM (random memory) in which information necessary for executing programs is written and read.・Access memory) 8.

As the external storage medium, a read-only nonvolatile storage medium such as a CD-ROM, and a writable and readable nonvolatile storage medium such as DAT (digital audio tape) are used. In addition,
The external storage medium is not limited to CD-ROM or DAT, but it is also possible to use a nonvolatile storage medium such as an IC card. The CD-ROM stores in advance map data obtained by digitizing (numerizing) each point on a road on a map. Information stored in this CD-ROM is read by a CD-ROM driver 10. CD-R
The read output of the OM driver 10 is decoded by the CD-ROM decoder 11 and sent to the pass line L.

On the other hand, the DAT is used as a so-called backup memory, and information is recorded or read by the DAT deck 12. When the vehicle power is cut off, information such as the vehicle's current location coordinates stored in the RAM 9 immediately before is transferred to the DAT encoder/data as buffer knob data.
It is stored in the DAT by being supplied to the DAT deck 12 via the decoder 13, and when the vehicle power is turned on, the
The information stored in the AT is read out by the DAT deck 12. The read information is sent to DAT encoder/decoder 1
RA by being sent to the path line L via
Stored in M9.

Turning the vehicle power on and off is detected by a detection circuit 14 that monitors the output level in front of a so-called accessory switch S of the vehicle. Vehicle power from a battery (not shown) that has passed through the accessory switch S is stabilized by a regulator 15 and supplied as power to each part of the device. Due to the time constant of the circuit, the output voltage of the regulator 15 does not fall instantaneously when the accessory switch S is turned off, and during this falling period, the buffer knob data is stored in the DAT as a sock-up memory. will be carried out.

When the vehicle is running, the CPU 7 calculates the running direction of the vehicle based on the output data of the direction sensor 1 at a predetermined period by a timer interrupt, and calculates the running distance and The vehicle's current location coordinates are determined from the driving direction, map data of a certain area including the current location coordinates is collected from the CD-ROM, and the collected data is stored in the RAM as a buffer memory.
9 and supplies it to the display device 16.

As a method for determining the running direction of the vehicle based on the output data of the direction sensor 1, a method described in Japanese Patent Application Laid-Open No. 130013/1983 may be used.

The display device 16 includes a display 17 such as a CRT, and a V
(Video) - A graphic memory 18 consisting of RAM, etc., one graphic controller that draws map data sent from the system controller 5 as image data in the graphic memory 18 and outputs this image data, and this graphic controller 1. The display controller 20 is configured to control display of a map on a display 17 based on image data output from a display 17. The input device 21 includes a keyboard, etc., including a trajectory key that commands the display of the running trajectory, and a speed UP key and DOWN key that commands acceleration and deceleration of the display speed following the running trajectory. It issues various commands to the system controller 5, such as commands and commands to accelerate or decelerate the displayed speed following the travel trajectory.

Next, the processing procedure for collecting traveling trajectory data executed by the CPU 7 will be explained with reference to the flowchart of FIG. 2. Note that this subroutine uses a constant distance da
While recognizing the current location of the vehicle each time it travels, a group of map data for a certain area including the current location is read out from the CD-ROM and displayed on the display 17 as a map around the current location of the vehicle, and the current location of the vehicle is also displayed on the map. It is assumed that this routine is called and executed at a predetermined timing during the execution of a main routine (not shown) that performs processing such as displaying the position of one's own troops.

The CPU 7 first determines whether the vehicle has traveled a certain distance db(ada) based on the output data of the distance sensor 3 (step 521), and if the vehicle has traveled a certain distance, the current location of the vehicle is recognized. Step 52
2) Then, the write address pointer is advanced by one data group (step 523).

By repeating this process every time the vehicle travels a certain distance db, a number of point data groups corresponding to the storage capacity of the ring buffer are sequentially stored as travel trajectory data. The travel trajectory data is sequentially updated with new travel trajectory data. In addition,
When storing the travel trajectory in the ring buffer, the travel trajectory data may be stored sequentially in all of the storage areas of the Ringer Sofa, or the start and end addresses of a specific area of the ring buffer may be specified using a delimiter pointer. Then, the travel locus data may be sequentially stored in the area defined by this delimiter pointer.

Next, the processing procedure for displaying the traveling trajectory executed by the CPU 7 when a command to display the traveling trajectory is given by manual key input on the input device 21 will be explained according to the flowchart in FIG. In response to a manual command, first set the read address pointer to an address where a group of point data, such as the starting point, of the traveling trajectory is stored (step 531), and read out the point data group from the ring buffer (step 53).
2) Next, a map data group of a certain range of area centered on the point coordinates based on the read point data group is obtained from the buffer memory (for example, the graphic memory 18), and the map and point coordinates are displayed on the display 17 with a cursor. The display device 16 is controlled to display the data (step 53B), and then the read address pointer is advanced by one data group (step 534).

Next, the CPU 7 determines whether the read address pointer matches the write address pointer or not in step 5.
35) If the two pointers do not match, then it is determined whether the read address pointer matches the previous delimiter pointer (step 536). If the read address pointer does not match the write address pointer or the break point, it means that the travel trajectory has not been displayed up to the final travel point, so the program waits for a predetermined time in the standby mode (step 537), and then the program The process moves to step S32. The reason for waiting for a predetermined time in the standby mode in step S37 is to scroll the map at the cycle of the time, and the processing procedure of this standby mode will be described later.

By repeating the above process, the point data group is read out from the ring buffer in order, and a map is set on the display 17 in the standby mode in step S37 so that the coordinate position of the point according to this point data group is the center. The travel trajectory will be displayed by scrolling periodically. If the read address pointer matches the write address pointer or the break pointer, it means that the travel trajectory has been displayed up to the final travel point.
The PU 7 ends a series of processes for displaying the travel trajectory.

Next, the processing procedure of the standby mode mentioned above will be explained according to the flowchart of FIG. 4.

The CPU 7 first sets an initial value in the timer counter (step 541), and then determines whether or not there is a key input from the input device 21 to command acceleration or deceleration of the displayed speed following the travel trajectory (step 542). If there is a key input that commands acceleration or deceleration, the CPU 7 increases or decreases the initial value of the timer counter by an amount corresponding to, for example, the input time of the key input (step 543), and then waits for a unit time (step 544). ). If there is no key human power to command acceleration or deceleration, the program moves directly to step S44. After waiting for unit time, CP
U7 counts down the count value N of the timer counter by "1" (step 545), and then determines whether the count value N is O or not (step 546), N4
If it is 0, the program returns to step S42, and N-0
If so, the program returns to step S32 in FIG.

According to this standby mode processing, by manually issuing a command to accelerate or decelerate the display speed using a key in the human-powered device 21, the scrolling cycle of the map when displaying the travel trajectory is changed to change the display speed at which the travel trajectory is followed. Since it can be set freely, it is convenient when displaying a driving trajectory in a specific section with emphasis among driving trajectories based on a large number of point data groups stored in the buffer memory.

In the above embodiment, the point data group is read out in the order stored in the ring buffer as travel trajectory data and the travel trajectory is sequentially displayed from the start point to the end point. However, in step S31, the read address pointer is set to the end point address. By setting the read address pointer and returning the read address pointer by one data group in step S34, the point data group is read out in the reverse order of the storage order and the travel trajectory is displayed sequentially from the end point to the start point. It is also possible to do so.

As described in detail, the in-vehicle navigation device according to the present invention recognizes the current location of the vehicle and collects and stores a group of point data indicating the point coordinates of the current location every time the vehicle travels a certain distance. In response to a command to display the traveling trajectory of the vehicle, the storage point data group of the storage means is sequentially read out in the storage order or in the reverse order at a cycle according to a preset display speed, and the readout point data is The configuration is such that it controls the extraction of a map data group centered on point coordinates from the storage medium and supplies the extracted map data group and readout point data group to the display means.

As a result, it is possible to display the driving trajectory while sequentially displaying a map of a certain area centered on the point coordinates based on the readout point data group, so it is possible to display the past driving trajectory on the display in an easy-to-read manner. This is useful for checking the driving route or the reverse route, and for providing directions the next time you travel the same route.

In particular, by sequentially reading the point data group at a cycle according to the display speed set by the acceleration or deceleration command,
By changing the scrolling cycle of the map when displaying the driving trajectory, you can freely set the display speed at which the driving path is traced.
This is convenient when displaying a driving trajectory in a specific section in a focused manner among traveling trajectories based on a large number of point data groups stored in the storage means.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the in-vehicle navigation device according to the present invention, FIG. 2 is a flowchart showing the processing procedure for collecting travel trajectory data executed by the CPU, and FIG. FIG. 4 is a flowchart showing the processing procedure for displaying the locus. FIG. 4 is a flowchart showing the processing procedure in standby mode executed by the CPU. Explanation of symbols of main parts 1... Orientation sensor 3... Distance sensor 5... System controller O... CD-driver 6... Display device 17...Display

Claims (2)

[Claims] (1) a display means for displaying an image according to a supplied display information signal; a reading means for reading a plurality of map data groups from a storage medium in which a plurality of map data groups respectively corresponding to a plurality of regions are stored; Current location recognition means that recognizes the current location of the vehicle and obtains a point data group indicating the point coordinates of the current location; and Point data collection that collects the point data group every time the vehicle travels a certain distance and sequentially stores it in a storage means. input means for setting a display command for a travel trajectory of the vehicle and a display speed for following the travel trajectory; and in response to the display command, for causing the display means to display the travel trajectory based on a group of stored point data in the storage means. and a travel trajectory display means for displaying, in response to the display command, the storage point data group of the storage means in the storage order or the reverse order according to the display speed set by the input means. a point data read control means for controlling the point data to be read out sequentially in a periodic manner; and a point data read control means for controlling to extract from the storage medium a map data group centered on point coordinates according to the read point data group from the storage means, and for controlling the extracted map data group and An in-vehicle navigation device comprising: display control means for supplying the readout point data group to the display means as the display information signal. (2) The reading means includes a buffer memory for storing a map data group read from the storage medium, and the display control means extracts a map data group centered on point coordinates according to the read point data group from the buffer memory. 2. The in-vehicle navigation device according to claim 1, wherein the in-vehicle navigation device is controlled to