JPH0364787A - Map display device - Google Patents

Abstract

PURPOSE:To accurately and rapidly execute the adjustment of a position to a desired spot by providing a means for comparing a linear movement quantity from a scroll starting point with a specified value and a means for changing a scroll speed when the linear moving quantity exceeds the specified value. CONSTITUTION:According to the designation from a keyboard 2, a microcomputer 6 reads out the map of a region where a vehicle is going to travel from an external memory 3 and makes it displayed on a CRT display 1. According to the designation by the joy stick of the keyboard 2, the travel starting position of the vehicle is displayed on a map displayed on the CRT display 1. Then, the travel distance and the moving direction of the vehicle in the case that the vehicle travels from the travel starting position are successively detected by a distance sensor 4 and a direction sensor 5, and the current position of the vehicle which is detected is displayed on the map displayed on the CRT display 1. When the linear moving quantity exceeds the specified value, the scroll speed is changed. Thus, the adjustment of the position to the desired spot is accurately and rapidly executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a map display device that displays a map or the like on a vehicle travel route, for example, for vehicle travel guidance.

(Prior Art) This type of map display device determines the moving direction of the vehicle from an initial position preset on a road map stored in a storage device based on output signals from a vehicle speed sensor and a direction sensor. The current position of the vehicle is calculated by calculating the distance traveled and displayed on the CRT display device inside the vehicle along with the road map stored in the storage device.

In such a map display device, in order to set the current position of the vehicle on the map displayed on the display device, correct the current position, or set the target point of the vehicle,
It is necessary to move a mark indicating the current position of the vehicle or a target point on a map displayed on a display device. Also,
Instead of moving such a mark, there is also a method of fixing the mark at approximately the center of the display screen and scrolling the displayed map with respect to the mark fixed at the center.

In any case, when moving the mark that indicates the vehicle's current position or target point relative to the map and aligning it with the desired point, the relative moving speed between the mark and the map should be adjusted to make alignment easier. If it is slowed down, it will take time to align if the desired point is far away, so the movement speed is set to two stages, and the movement speed is slowed down immediately after the start of movement, and the relative movement between the two is more than a predetermined amount. When this occurs, the moving speed is increased to reach the desired point quickly.

(Problem to be Solved by the Invention) In the conventional map display device described above, the movement speed is slowed down immediately after the start of movement, and when the relative movement amount between the two exceeds a desired amount, the movement speed is reduced. Although it is fast,
Even though it is near the desired point, if you are unable to accurately align with the desired point and wander around near the desired point, this may cause the amount of movement to exceed the specified amount, resulting in , there is a problem in that the moving speed becomes faster and it becomes increasingly difficult to adjust to a desired point.

The present invention has been made in view of the above, and its purpose is to display a map that improves the ease of adjusting to a desired point by changing the scrolling speed when the amount of linear movement reaches a predetermined value. The goal is to provide equipment.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, a map display device of the present invention is a map display device that scrolls a map displayed on a screen to display a desired point on the screen. a comparison means for comparing the amount of linear movement from the scrolling start point with a predetermined value when scrolling of the map displayed on the map is started; The gist is to have a changing means for changing.

(Function) In the map display device of the present invention, the scroll speed is changed when the amount of linear movement exceeds a predetermined value.

(Example) Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a block diagram showing the circuit configuration of a map display device according to an embodiment of the present invention. The map display device shown in the figure is mounted on, for example, a vehicle to guide the vehicle's travel, and has a CRT display 1 that displays a map on the travel route of the vehicle and the current position of the vehicle on the map. , this CRT display 1 is connected to a microcomputer 6. The microcomputer 6 is a CPU
6 a + Consists of ROM 6b, RAM 6c, V-RAM 6d and 1/F circuit 6e, CRT display 1
are connected via an I/F circuit 6e.

In addition to the CRT display 1, a keyboard 2, an external memory 3, a distance sensor 4, and an orientation sensor 5 are connected to the I/F circuit 6e of the microcomputer 6. The keyboard 2 is used to input various information to the microcomputer 6.
has a joystick that moves a cursor displayed on the map displayed on the CRT display 1 to indicate the current position of the vehicle, a target point, etc., or scrolls the map.

The external memory 3 stores map data for a certain range necessary for vehicle driving guidance, supplies the microcomputer 6 with map data of a specific area instructed by the microcomputer 6, and controls the microcomputer 6. The map can then be displayed on the CRT display 1.

The distance sensor 4 detects the distance traveled by the vehicle, and generates a pulse every time the vehicle travels a unit distance. The direction sensor 5 detects the direction of travel of the vehicle by detecting the earth's magnetic field, converts the detected signal direction into a digital signal, and outputs the signal.

The microcomputer 6 stores a map of the area in which the vehicle is going to travel in an external memory 3 based on instructions from the keyboard 2.
It is read out from CRT and displayed on CRT display 1, and the CR
The travel start position of the vehicle is displayed on the map displayed on the T-display 1, and the distance sensor 4 measures the travel distance and moving direction of the vehicle when the vehicle travels from this travel start position.
and the direction sensor 5, and the current position of the detected vehicle is displayed on a map displayed on the CRT display 1.

In such an operation, the map display device of the present invention accurately aligns and displays the starting position, current position, or target point of the vehicle on the map displayed on the CRT display 1. Although it is designed to perform the operation quickly and accurately, the operation will be explained below with reference to the flowcharts from FIG. 2 onwards.

First, referring to FIG. 2, the microcomputer 6
The general flow of operations performed by will be explained.

In FIG. 2, when the map display device starts up, the operator initializes the current position of the vehicle using the keyboard 2 (step 21).
0), this current position is stored in the RAM 6c. Then, after interrupt permission is set (step 220),
Integral integration processing that occurs every time the vehicle travels a unit distance is performed (step 250), and when the current position of the vehicle moves, the current position is updated (step 230.2).
40). In the integration processing, the traveling direction of the vehicle is read from the direction sensor 5; the current position of the vehicle expressed in two-dimensional coordinates is advanced by a unit distance in the direction of travel from the direction sensor 5. Also, if there is a movement in the position of the vehicle,
The map displayed on the CRT display 1 is scrolled relative to the vehicle, or the current position of the vehicle displayed on the map is updated, so that the current position of the vehicle can be changed to, for example, FIG. 6(a) or FIG. As shown in FIG. 7(a), the map is displayed on the CRT display 1 using arrow marks or the like.

Next, with reference to FIG. 3, the operation when scrolling the map in order to match the current position of the vehicle, etc. on the map will be explained.

First, when you operate the joystick to scroll the map in order to match the vehicle's current position etc. on the map, an interrupt occurs and the process shown in Figure 3 starts, and the center of the screen displayed on CRT display 1 is displayed. The map coordinates of are calculated and stored as initial coordinates (Xo, Yo) (step 300). Note that the joystick is specifically provided, for example, near the CRT display 1, and can be operated in eight directions. Further, in this case, a cross mark is always displayed at the center of the screen as shown in FIGS. 6(a) and 6(b). Also, FIG. 6(a).

In (b), the current position mark of the vehicle is indicated by an arrow.

Next, it is determined whether or not the joystick is pressed (step 310). If the joystick is not pressed, the process proceeds to step 370, where the current position mark is erased and the current position is moved to the center of the screen, that is, the center point of the cross mark. The position mark is displayed (step 380), and the process ends.

If the joystick is pressed in step 310, the map is scrolled one dot in the opposite direction to the direction in which the joystick is pressed (step 320). The map coordinates of the center of the display screen after this scroll movement are calculated and stored as coordinates (X, Y) (step 330). Then, the scrolled coordinates (X, Y) and the above-mentioned initial coordinates (Xo, Yo
) is calculated, and it is checked whether this straight line distance is greater than or equal to a predetermined distance (step 340).

If the straight line distance is not greater than the predetermined distance, step 3
Returning to step 10, the map scrolling operation is repeated, but if the distance is greater than the predetermined distance, the process proceeds to step 350, where it is checked again whether the joystick is pressed.
If pressed, scrolls the map 5 dots in the opposite direction of the joystick being pressed, thereby scrolling the map rapidly (step 360);
Returning to step 350, the same process is repeated. Also, if the joystick is not pressed in the check at step 350, the process advances to step 370, where the current position mark is erased as described above and the current position mark is displayed at the center point of the cross mark in the center of the screen. 380),
Finish the process.

Next, referring to FIG. 4, the operation of another embodiment of the present invention in which the cursor is moved instead of scrolling the map as described above will be described.

First, when the joystick is operated, an interrupt occurs and the process shown in FIG. 4 starts, and the current position mark displayed as shown in FIG. 7(a) is erased from the CRT display 1 (step 400). , a cross mark as a cursor mark is displayed at the map coordinate point (Xo, Yo) where this current position mark was displayed (step 410).
. Then, it is checked whether the joystick is pressed (step 420), and if not, the process proceeds to step 470, where the cross mark is erased,
Then, the current position mark is displayed at the point where the cross mark was displayed, and the process ends (step 480).

In the check at step 420, if the joystick is pressed, the cross mark is moved one dot in the direction in which the joystick is pressed, and the map coordinate point of the cross mark is stored as (x, y) (step 43).
0). Then, this moved coordinate (X, Y) and the previously mentioned coordinate (Xo.

Straight line distance between (Xo, Yo) - (X.Yo)

Y) and checks whether this straight line distance is greater than or equal to a predetermined distance (step 44o).

If the straight line distance is not greater than the predetermined distance, step 4
Return to step 20 and repeat the cross mark movement loop,
If the distance is greater than the predetermined distance, proceed to step 450;
Check whether or not the joystick is pressed. If it is pressed, move the cross mark 5 dots in the direction in which the joystick is pressed, thereby moving the cross mark at high speed. Step 460), Step 45
Return to 0 and repeat the same process. Also, step 450
When the joystick is not pressed, the process proceeds to step 470, where the cross mark is erased as described above, and the current position mark is displayed at the point where the cross mark was displayed (step 480). end.

In the above embodiment, there are two types of cursor movement speeds; the slow side is a cursor movement of 1 dot per loop, and the high speed side is a cursor movement of 5 dots per loop. However, the cursor movement speed is different from a loop. Due to the processing power of the microcomputer 6, the high-speed side allows the operator to read the map while the cursor moves from one end of the screen to the other, and the low-speed side allows the operator to accurately position the map at any point. It is preferable to set it as speed. Further, it is preferable that the predetermined distance be within a range that can be adjusted by, for example, 90% of the operators at the higher speed of the two types of cursor speeds.

FIG. 5 is a flowchart showing part of the operation of yet another embodiment of the present invention. The processing flow shown in the same figure is between steps 430 and 440 in FIG.
It is inserted immediately after.

Then, in step 500 of FIG. 5, the map density of the map displayed on the CRT display 1 is calculated, and it is checked whether or not this map density is higher than a predetermined value. If the value is low (step 51o), the cursor is moved three dots in the direction in which the joystick is being pressed, thereby increasing the cursor movement speed (step 520). In this case, the map density calculation is performed using, for example, the CRT display 1.
It is conceivable to do this by using the road display area value on the screen, the number of displayed place names, road names, etc.

〔Effect of the invention〕

As explained above, according to the present invention, when the amount of linear movement exceeds a predetermined value, the scroll speed is changed, so it is possible to accurately and quickly adjust to the desired point.
Operability can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the circuit configuration of a map display device according to an embodiment of the present invention, FIGS. 2 and 3 are flow charts showing the operation of the map display device of FIG. 1, and FIG. 4 is a block diagram showing the circuit configuration of a map display device according to an embodiment of the present invention. FIG. 5 is a flowchart showing a part of the operation of still another embodiment of the present invention, and FIG. 6 is a CRT used to explain the operation of FIG. 3.
Figure 7 shows the screen displayed on the display.
FIG. 3 is a diagram showing a screen displayed on a CRT display used to explain the function of the diagram. 1...CRT display, 2...Keyboard, 3...External memory, 4...Distance sensor, 5...◆Direction sensor, 6...Microcomputer.

Claims (1)

[Claims] A map display device that scrolls a map displayed on a screen to display a desired point on the screen, and when scrolling the map displayed on the screen starts, an amount of linear movement from the scroll start point is set as a predetermined value. A map display device comprising a comparison means for making a comparison, and a changing means for changing a scrolling speed when the linear movement amount exceeds a predetermined value as a result of the comparison.