JPH029688B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a course guidance device, in particular, an electronic display mounted on the driver's seat of a moving object, such as a passenger car, and a road map displayed on the display screen of the display. The course guidance device extracts the current position of the passenger car based on the outputs of the direction sensor and speed sensor, and displays the current position of the passenger car by superimposing it on the road map. The present invention relates to a course guidance device that, when a point at a predetermined distance is reached, can enlarge the range from the point on the road map to the destination and display it on the display.

Recently, as microcomputers have become relatively easy to obtain, automobile driving navigators using microcomputers have been considered. One of this type of navigator is a direction sensor and a speed sensor.
The vehicle is equipped with a sensor, extracts the driving position of the car based on the outputs of the direction sensor and speed sensor, and plots the driving trajectory on a cathode ray tube display, for example, as well as a storage device that stores information about the road map. A system is being developed that reads the contents of the storage device, displays the road map on the display, and guides the user on a course so that the travel trajectory extends along the roads on the road map.

In such a system, for example, if the vehicle progresses and the vehicle's driving position reaches the peripheral edge of the road map displayed on the display screen and deviates from the road map,
The vehicle is automatically updated with a road map of an adjacent area and the travel trajectory is displayed in correspondence with the updated road map, or the road map displayed on the display is enlarged as necessary. If it were possible to display the information, it would be convenient to use and the effect of course guidance would be even greater, so there is a strong demand for such a course guidance device.

The present invention aims to meet the above-mentioned demands, and in particular, when the current position of the vehicle displayed on the display approaches a pre-entered destination, a map from the current position to the destination is automatically displayed. The purpose is to zoom in on information and enable accurate course guidance. This will be explained below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram illustrating the manner in which position information is stored in the locus memory shown in FIG. 1, and the manner in which it is read out.
The figure is an explanatory diagram explaining the read range of the memory.
Figure 5 and Figure 5 are explanatory diagrams explaining the conversion of map data, Figure 6 is an example of how external map information is divided, and Figure 7 is an explanation explaining how to input the initial settings of the start point and destination. 8 are explanatory diagrams for explaining the zoom up function.

Reference numeral 7 in the figure is a direction sensor, which detects the direction in which the vehicle is traveling, for example, corresponding to a certain reference direction. Reference numeral 8 denotes a speed sensor which generates clock pulses corresponding to, for example, the rotation of the wheels. 9 represents an input key, and 10 represents a display.
The input keys 9 are used for inputting initial settings of the current position and destination on the map information displayed on the display 10, inputting the scale setting of the map information, inputting the traveling trajectory for movement, and the like.

Direction information from the direction sensor 7 is converted into a digital signal by an A/D converter 11, and converted into angle information by an angle conversion section 12. On the other hand, the clock pulses from the speed sensor 8 are counted by a pulse counter 13 so that a sample clock can be output, for example, every 10 revolutions of the wheel. Every time the sample clock is issued, the angle information from the angle converter 12 is
The signal is supplied to the X component calculation section 15X and the Y component calculation section 15Y via the angle correction section 14. Then, the calculation unit 15X extracts the change on the X-axis based on the direction (north), for example, and adds it to the cumulative value of the change on the X-axis up to that point to calculate the current position coordinates on the X-axis, and the trajectory memory 16 The data is supplied to be stored in bank #0 (BANK). In addition, the calculation unit 15Y similarly extracts the change on the Y-axis, adds it to the cumulative value of the Y-axis change up to that point, calculates the current position coordinate on the Y-axis, and stores the coordinates in the #0 bank (BANK) of the trajectory memory 16. Supply to be stored in. That is, for example, when the coordinates at the start point are (0, 0), the coordinate values of the current position are calculated and supplied to the trajectory memory 16.

The contents of the trajectory memory 16 are read out in order to be transferred to the trajectory memory 18, and the memory conversion processing section 17
A predetermined conversion is performed in the locus memory 1.
It is stored on 8. In this case, conversion corresponding to the scale of the map is performed, which will be described later with reference to FIG. The contents of the locus memory 18 are read out to be transferred to the locus display memory 20, subjected to a predetermined transformation such as parallel movement in the memory conversion processing section 19, and then stored in the display memory 20. The contents of the display memory 20 correspond to the image graphics displayed on the display 10, and are read out via the display drive circuit section 21 and supplied to the display 10.

22 is a scale register, which is stored in the external storage device 1.
The display range and scale information of the map information stored in the map information are inputted from the coordinate detection circuit 31 and set. The contents of the register 22 are supplied to the memory conversion processing section 17 and used when transcribing the contents of the trajectory memory 16 to the trajectory memory 18. Further, the contents of the register 22 are stored in the sampling interval determining section 23.
The information is notified to the memory address generator 24 and used for address generation by the memory address generator 24, and the processing during this time will be described later with reference to FIG. The contents of the register 22 are also notified to the memory conversion processing section 3 at the same time, and are used when transcribing the map information stored in the map information register 2 to the display memory 20.

Reference numeral 25 denotes a θ correction register, in which a correction value is set using the input key 9 to correct the angular deviation between the travel trajectory and the map when the vehicle is actually traveling on a road. Then, by using the correction value set in the adjustment mode, that is, the correction value set to correct the angular deviation in the adjustment mode when the direction sensor 7 is mounted on the vehicle body, etc., the contents of the trajectory memory 16 are transferred to the trajectory memory. It is used to correct the above-mentioned angular deviation when transcribing to 18.

Reference numeral 26 denotes an X, Y, and θ correction register, into which correction data is set via the input key 9 in order to correct slight distortion between the road on the map information and the travel trajectory. Then, when the contents of the locus memory 18 are transferred to the display memory 20, the above distortion is corrected in the memory conversion processing section 19.

Reference numeral 27 is a register for parallel movement, and when changing the scale of the map information and the traveling trajectory, movement amount information is input from the coordinate detection circuit 31, and the movement amount information is inputted to the trajectory memory 18.
When transcribing the contents to the display memory 20, the memory conversion processing section 19 performs the above-mentioned parallel movement.

28 is a count value memory in which the contents of the pulse counter 13 are set at the time when the automobile passes, for example, a railroad crossing or a bridge, and are displayed on the display screen of the display 10 in a manner different from the above-mentioned traveling trajectory 32. It is used to plot the above passing position. That is, a memory mark of a brighter point is left in the traveling trajectory 32 and is used to confirm the traveling route. Further, reference numeral 29 denotes a comparison processing section, which is used to write a mark on the display memory 20 corresponding to a point corresponding to the contents of the count value memory 28. Furthermore, 30 is an encoder that generates a code corresponding to input information from the input key 9.

Note that the display drive circuit 21 shown in FIG.
When the driver receives the suppress mode instruction information from the encoder 30 and the driving information from the speed sensor 8 and is traveling alone, by selecting the suppress mode, the display on the display 10 is changed to It has a display suppression function that suppresses the display while driving so that the driver is not undesirably distracted by the display 10 while driving. Note that if the suppress mode is canceled, the display can be displayed on the display 10 even during the above-mentioned driving.

The above-mentioned X component calculation section 15X, Y component calculation section 15
Regarding the main processes in Y, the trajectory memory 16, the memory conversion processing unit 17, and the trajectory memory 18, the second
This will be explained in detail with reference to the drawings.

As described above, the X-component calculation section 15X and the Y-component calculation section 15Y calculate the coordinates of the starting point, for example, (0,
0), the coordinates (x _i , y _i ) of the vehicle traveling position at the time corresponding to each sample clock are calculated. This result is stored in the trajectory memory 16, and if this aspect is illustrated corresponding to the traveling trajectory 32, it can be considered as something like the one on the left side of FIG. 2A.
That is, from the coordinates (0, 0) of the starting point, (x _o-1 , y _o-1 ), ... (x ₂ , y ₂ ), (x ₁ , y ₁ ), (x ₀ ,
y ₀ ) is stored in the trajectory memory 16. The trajectory memory 16 includes, for example, #0 bank (BANK) for 128 words, and #1 bank to #5 for 64 words.
It has a bank. And the illustrated coordinates (x ₀ ,
128 coordinates starting from y ₀ ), i.e. (x ₁₂₇ , y ₁₂₇ )
are sequentially stored in the #0 bank using a push-down method, and the coordinate information overflowing from the #0 bank is extracted one in two and stored in the #1 bank using a push-down method. For example, the overflowing coordinate information is extracted one in two and stored in bank #2 in a push-down manner. The same holds true for storage in banks #3 to #5.

In other words, as shown in FIG. 2B, 128 pieces of coordinate information from the current point (x ₀ , y ₀ ) are stored in bank #0 for each sample clock, and the coordinate information for the current point (x 0 , y ₀ , y ₀ ) from the 129th to 256
Up to the first one, 64 pieces of coordinate information are stored in bank #1 every two sample clocks.
Similarly, from the 513th to the 1024th coordinate information, one piece of coordinate information is stored in bank #2 for 4 sample clocks for 64 pieces. Furthermore, bank #3 has one clock for every 8 sample clocks, bank #4 has one clock for every 16 sample clocks, and bank #5 has one clock for every 16 sample clocks.
One sample is stored in the bank for every 32 sample clocks.

When map information is used as described above, the travel trajectory on the display 10 should be displayed in a form that matches the scale of the map information. For this reason, when displaying the travel trajectory 32 corresponding to the map information with the smallest scale ratio, the coordinate information on the #0 bank is sampled at an interval of "1" (sampling is performed) as shown in FIG. 2C. ) to generate a travel trajectory consisting of 128 points. In addition, when using map information with a scale factor of approximately twice, read coordinate information for 64 pieces from bank #0 at a sampling interval of "2" (extract every other piece), and read coordinate information from bank #1 at a sampling interval of "2" (extract every other piece). "1" reads 64 pieces of coordinate information, totaling 128
A travel trajectory consisting of points is generated. Similarly, if you use a map with a scale of about 32 times,
Every 32 pieces from #0 bank, every 16 pieces from #1 bank, every 8 pieces from #2 bank, 4 pieces from #3 bank
Every two points are read out from bank #4 and every two points are read out from bank #5 to generate a travel locus consisting of a total of 128 points.

When the contents of the trajectory memory 16 are transferred to the trajectory memory 18, scale information is set in the scale register 22 in accordance with the above-mentioned scale rate, and the above-mentioned sampling interval is determined accordingly. A memory address is generated. Then, the locus memory 16 is accessed based on the address. During this time, correction is performed based on the contents of the θ correction register 25 described above, but detailed explanation thereof will be omitted. However, by extracting 128 points from the contents of the trajectory memory 16,
, the memory conversion processing unit 17 performs the following steps.
As conceptually shown on the right side of FIG. 2A, the current coordinate position (x ₀ , y ₀ ) is the origin (0, 0), and the previous coordinate position is (x ₁ −x ₀ , y ₁ − y ₀ ), the previous coordinate position is converted to (x ₂ −x ₀ , y ₂ −y ₀ ), etc., and is transferred to the trajectory memory 18. By doing so, when displaying on the display 10, it is possible to process the current position as a reference, and various adjustments can be made easily.

Further, in FIG. 1, reference numeral 1 denotes an external storage device, which has a larger storage area than the display memory 20. As shown in FIG. The external storage device 1 stores, for example, map information of the largest scale for all of Japan, and its interior is divided into a plurality of blocks, ie, a memory block 1a, . . . , a memory block 1n. The memory block 1a stores only roads that are always displayed regardless of the display scale, such as expressways and national roads, while the memory block 1b stores roads that should be displayed at any scale, such as prefectural roads. Similarly, memory block 1n stores roads that are displayed only at the minimum scale level. That is, in the external storage device 1, weights are assigned to each road so that roads can be selected for display according to the display scale level, and the map information is stored for each weight.

When initializing the starting point and destination, for example, pre-divided map information is displayed on the display 10 and selected using the input key 9, as shown in FIG. In this case, the sixth
In Figure A, by inputting the map number using the input key 9, the scale of the map information is reduced as shown in Figure B, and by repeating this selection operation, as shown in Figure 7. , reduce the scale rate of the map information to the minimum. By doing this,
The operator can input the starting point and destination extremely accurately, improving the setting accuracy. As a means of input, for example, as shown in FIG. 7, a cursor is displayed on the display 10, the cursor is arbitrarily moved in each direction of ± The installed set key allows input in association with map information.

By performing the input operation as described above, coordinate information of the start point and destination is input to the coordinate detection circuit 31. The coordinate detection circuit 31 notifies the display range determination circuit 4 of the coordinate information, and the display range determination circuit 4 determines the range of map information to be displayed on the display 10. Based on this result, the external storage device 1
The map information stored in the third
As will be described later with reference to FIGS. 4 and 5, map information corresponding to the map information register 2 is read out. This map information is subjected to conversion processing for predetermined enlargement etc. by the memory conversion processing section 3, and is transferred to the display memory 20. The map information stored in the display memory 20 has a scale that allows the start point and destination to be displayed on the same screen, and when displayed on the display 10 via the display drive circuit 21, The start point and destination can be viewed on the display 10 at the same time as the above map information.

Driving mode, i.e. when the car is running,
For example, as shown in FIG. 8, the current position 37 of the automobile approaches the destination. Display 1
For example, if the scale rate of the map information displayed at 0 is
Assuming that the ratio is 1/800,000, if the car continues to drive and approaches the destination, the scale of the map information is too large, making it difficult for the driver to judge whether or not the destination has been reached. It is expected that this will be difficult. The present invention enables accurate course guidance using a zoom-up function as described below.

In FIG. 8, the vector distance L between the starting point (X _o , Y _o ) and the destination (X _o , Y _o ) initialized as described above and the current position 37 (X _o-2 ,
Vector distance l between Y _o-2 ) and destination (X ₀ , Y ₀ )
is expressed by the following equation.

The coordinate detection circuit 31 performs the arithmetic processing shown in the above equation (1) from the scale information of the map information displayed on the display 10 and the coordinate information of the current position 37, and calculates vector distances L and l. , Furthermore, for example, it is determined whether the relationship 2l≧L...(2) is satisfied.

If the above equation (2) is satisfied, that is, the current position 37 of the car approaches the destination, and for example, the vector distance l between the current position 37 and the destination is 1/ of the distance L between the start point and the destination. 2 or less, the new scale information is notified to the scale register 22, the memory conversion processing unit 17 is notified of a command to convert the scale rate of the trajectory information, and the current A command is sent to move the position 37 to the coordinates corresponding to the above map information. Further, the scale register 22 sets the scale rate of the map information at a magnification corresponding to the degree of arrival to the destination expressed by the ratio of the vector distances L and l.
The memory conversion processing unit 3 is notified to perform processing to enlarge the map information.

In other words, if the scale of the map information displayed on the display 10 is 1/800,000 as described above, when the current position 37 falls within the area 38 inside the broken line shown in FIG. That is, when the distance has just decreased to 1/2, the scale of the map information is zoomed up to 1/400,000, and the trajectory information is zoomed up accordingly. Similarly, for example, when the distance to the destination becomes 1/4 of the total distance, the scale of the map information is set to 1/200,000, and by zooming up, the destination is constantly It is possible to clearly confirm where the current position 37 of is located on the display 10.

However, if you continue to zoom up as described above, the zoom will continue indefinitely, so
For example, the minimum unit of scale for map information is set to 1/50,000, and when the zoom is repeated until the scale reaches 1/50,000, no further zooming is performed, and the destination of the car is Guide the course until.

Next, a method for displaying the map information stored in the external storage device 1 described above on the display 10 at an arbitrary scale will be described below in FIGS. 1, 3, and 4.
This will be explained with reference to the drawings and FIG.

In FIG. 1, when a start point and a destination are inputted to the coordinate detection circuit 31 by the input key 9 as described above, the start point and the destination are displayed simultaneously on the display 10. The scale factor of the map information is notified to the display range determining circuit 4, and the range of the map information is determined. That is, by specifying the scale factor and the positions of the start point and destination to be displayed, the range of map information to be displayed on the display 10 is determined, and in order to display the map, each memory The readout range of the data stored in the blocks 1a, 1b...1n is determined, and for example, the readout data range 33 of each memory block 1a, 1b...1n as shown in FIG. 3 is determined.

The coordinate detection circuit 31 receives scale data from the input key 9 (the scale at which map information is divided in advance), scale information of map information input from the memory conversion processing section 3, and input from the memory conversion processing section 19. The scale information of the input travel trajectory is input. The display range determining circuit 4 outputs the coordinate position information of the current position, the coordinate position information of the destination, and the range information of the map information to be displayed to the coordinate detection circuit 31.
The range and scale of the map information to be displayed are determined.

The display memory stage determining circuit 5 stores data of memory blocks to be read out from among the memory blocks 1a, 1b, . Then, the display block group 34 shown in FIG. 3 is determined. For example, if you specify a scale of 1/400,000, the traffic information that is necessary is for major roads such as expressways, national highways, and prefectural roads, and there is no need to display other narrow roads, and the determination is stored in the display memory. External storage device 1
Among the stored contents, the one to be displayed is determined and output.

Next, the output of the display memory stage determination circuit 5 is input to the display memory address circuit 6, and the display memory address circuit 6 specifies the address of the memory block to be displayed, reads out the map data of the memory block, and stores the map data in the map information register 2. Store in. The map data stored in the map information register 2 is transferred to the memory conversion processing section 3, and the memory conversion processing section 3 performs the following conversion on the transferred data according to the display scale and transfers it to the display memory 20. .

The memory conversion processing unit 3 stores the map information data stored in the map information register 2 and the scale register 22.
The memory conversion processing unit 3 processes the map information data according to the scale data. For example, map data 35 shown in FIG.
When converting an area having twice the length (four times the area) into one suitable for the display memory 20 of the map data 36 shown in FIG. 4B, the following processing is performed.

Adjacent 4 bits of the map data 35 are made into a set and correspond to 1 bit of the map data 36, and if there is even one "1" indicating a road in the set as shown in FIG. 5A, the map is created. A "1" is written to the corresponding address of the data 36, and if all four bits are "0" as shown in FIG. 5B, a "0" is written to the corresponding address of the map data 36. The map data is converted in this manner, and by specifying the number of conversions of the map data, data corresponding to the scale can be freely set.

As explained above, according to the present invention, from main roads to narrow roads, such as alleys, are stored in the memory, and the desired starting point, current position, and destination of the vehicle are displayed on the display at an arbitrary scale. can. In addition, the displayed map information automatically zooms in according to the degree to which the destination has been reached, allowing accurate and simple course guidance. In other words, for example, when a car is driving far away from its destination, it is likely to be traveling on major roads, and not only are non-major roads unnecessary, but displaying them would actually overwhelm the screen. becomes complicated and difficult to see. on the other hand,
Detailed road information is required when approaching a destination, but according to the present invention, it is possible to meet these demands and automatically display appropriate information. Furthermore, there is no need to manually replace the map sheet, and the displayed map can be changed just by key operation, so it has excellent operability. It is also possible to allow the driver to instruct whether or not to select the automatic zoom-up processing function using an input key or the like.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram illustrating the manner in which position information is stored in the locus memory shown in FIG. 1, and the manner in which it is read out.
The figure is an explanatory diagram explaining the read range of the memory.
Figure 5 is an explanatory diagram explaining the conversion of map data, Figure 6 is an example of how external map information is divided, and Figure 7 is an explanation explaining how to input the initial settings of the start point and destination. 8 are explanatory diagrams for explaining the zoom up function. In the figure, 1 is an external storage device, 2 is a map information register, 3 is a memory conversion processing unit, 4 is a display range determination circuit, 5 is a display memory stage determination circuit, 6 is a display memory address circuit, 7 is a direction sensor, 8 is the speed sensor, 9 is the input key, 16 is the trajectory memory,
20 represents a display memory, and 31 represents a coordinate detection circuit.

Claims (1)

[Claims] 1. Equipped with a direction sensor and a speed sensor,
It is equipped with a display that plots and displays a travel trajectory in response to the output from the direction sensor and speed sensor, and displays a map superimposed on the travel trajectory displayed on the display, A course guidance device that displays a position includes at least a map information storage section in which each memory block stores map information selected according to the scale level, and a map information storage unit that detects the coordinates of the current position and calculates the degree of arrival to the destination. and a coordinate detection/display range determining unit that changes scale information so that the scale rate decreases in multiple steps at a predetermined rate according to the degree of arrival to the destination, and the above map information storage according to the scale information. a first memory conversion processing section that processes map information read out from the map information; and a second memory conversion processing section that converts travel trajectory information to correspond to map information according to scale information; A course guidance device characterized in that the display is configured to display a travel trajectory and a map according to the above.