JPS5837543B2 - Siyariyouichihiyoujisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for displaying the position of a vehicle while it is running, and more specifically, it displays the current position of the vehicle on a map having an arbitrary scale as the vehicle travels. The present invention relates to a device that does this.

Devices that detect and display the position of moving vehicles, ships, etc. include radars based on the PPI system, Loran, Detsuka, and the like.

However, these devices detect their own position on the chart by emitting radio waves from themselves and receiving reflected waves from objects, or by receiving radio waves from fixed stations. This is extremely complicated and cannot be applied to a simple position detection device that detects the moving position of a car, for example.

In view of this, the present applicant combines his own traveling distance and the traveling direction detected for each unit traveling distance.
A simple position display device that determines the route and traces it on a display device with a map in the background has already been proposed.

FIG. 1 is a block diagram of this position display device.

1 is a distance determination circuit, 2 is a step pulse generator, 3 is a direction sensor, 4 is a display device drive circuit, 5 is a display device, and 6 is a position adjuster.

The distance determination circuit 1 detects the distance from the trip meter output, sends a signal every unit distance (travel distance corresponding to the basic display interval of the display device 5), and triggers the step pulse generator 2.

Therefore, the step pulse generator 2 generates a step pulse every time the vehicle travels the basic display distance, and drives the display drive circuit 4 one step at a time.

Further, the direction sensor 3 detects the advancing direction of the own army, and is configured using, for example, a magnet.

The output of the direction sensor 3 is detected every time a step pulse is generated, and the display drive circuit 4 determines the drive direction of the display point for each step.

Therefore, if the starting position of the display point is determined in advance on the display device 5 (point a), the display point will automatically move according to the progress of the car, and the display point will be inserted into the back of the display device 5. Combined with the map, it displays the progress position of your army.

The position adjustment device 6 is used to correct long-term errors caused by meandering of the vehicle, etc., and manually drives the display drive circuit 4 to correct the position.

However, in this device, the display device 5 is composed of a display grid, as shown in FIG.
By moving the display point one-dimensionally in both Y directions, a two-dimensional display is achieved as a result.

That is, if a vehicle starts from points e and B in the figure and the direction sensor 3 detects north after traveling a unit distance of, for example, 10 meters, the display point moves to e and C.

Similarly, when the sensor 3 detects east after traveling further Iom, the display points become f and C.

Therefore, the vehicle moves from points e and B to points e and C, and from points e and C to point f.
, C, etc., this is fine when moving along the X and Y axis directions, but when moving diagonally, for example northwest, from points f and D to points e and E, the actual running However, since this 10 m is converted into a strike direction of 1/10 m on the X and Y axes and calculated on the display device 5, it is displayed as a travel of 10 Ji m on the display device.

As described above, in the devices that have already been submitted, errors occur when traveling in diagonal directions, and as these errors are accumulated, a large error that cannot be ignored occurs in the position display on the display device.

The present invention has been made to address this problem, and is an improvement in that the cycle of step pulse generation is controlled based on the output of the direction sensor so that the correct travel distance is displayed when traveling in an oblique direction.

The apparatus of the present invention will be described below in detail by showing examples.

In the embodiment shown below, step pulses are generated by further subdividing the unit step pulse in order to prevent running errors due to zigzag running or sharp curves within a unit distance (for example, 10 m), and the step pulses are generated at these subdivided intervals. Perform direction detection,
This is accumulated to display a display that is closer to the actual distance traveled.

For example, if the interval between the grid points on the display device 5 is 1 mm, on a 1/10,000 scale map, this 1 mm corresponds to 10 doors in actual operation.
Generates every 0m run.

However, if this is further divided into 10 equal parts, a direction detection pulse will be generated every 11 rL of travel, so 1? ? L
The position is detected and stored every time.

Since zigzag travel at a distance less than this is unlikely, more accurate position display is possible.

FIG. 3 shows a schematic configuration of the direction sensor 3 shown in FIG. 1, and FIG. 4 is a circuit diagram of a main part of an embodiment of the present invention.

First, the direction detection method will be briefly described with reference to FIG.

In FIG. 3, reference numeral 7 denotes a magnetic needle rotatably supported on a substrate 8, and light receiving elements 10 are arranged on the substrate 8 in a rectangular shape as shown in the figure.

9 indicates the rotation axis of this magnetic needle 7.

The substrate 8 is fixed to the vehicle body with the direction of the light-receiving elements 11 of the light-receiving elements 10 aligned with the traveling direction, and is irradiated with light from above.

Therefore, at such a direction center 3, the traveling direction of the vehicle is always indicated in the direction of the light receiving element 11, and north is indicated by the magnetic needle 7.
It is detected by the output of the lower photodetector.

Therefore, the traveling direction of the vehicle can be easily detected from the relationship between the two.

If the light-receiving element 11 has an output, it means that the vehicle is moving north, and if the light-receiving element 23 has an output, it means that the vehicle is moving east.

The output of each light-receiving element is determined by the AND gate 30 shown in FIG.
31, 32, . . . , 37 as appropriate.

FIG. 4 is a circuit diagram of a main part of an apparatus according to an embodiment of the present invention.

First, in FIG. 4, 42 is a distance judgment correction circuit, and the first
This corresponds to the distance determination circuit 1 of the conventional device shown in the figure.

43 is an OR gate, 44 is a pulse generation circuit, and the output of this pulse generation circuit 44 is connected to each AND gate 30 described above.
, 31...37 and similarly and gate 3
B, 39, 40. 41.

The output of the AND gate 45 is input to the other input of the OR gate 43 .

Both the low frequency pulse from the low frequency oscillator 46 and the output of the OR gate 47 are input to the AND gate 45 .

Two contact outputs of changeover switches 48 and 49 are introduced to the input side of the OR gate 47.

The changeover switches 48 and 49 are for manually driving the display points on the display device 50, and when the OR gate 47, low frequency oscillator 46, AND gate 45, and OR gate 43 are in the positions shown in FIG. A regulator 6 is configured.

That is, the changeover switches 48 and 49 are each three-contact switches, and are normally set to the state shown in the figure. For example, when the changeover switch 48 is manually operated to the D contact side, the OR gate 47 is opened. , a low frequency pulse is introduced into the OR gate 43 via the AND gate 45, and the pulse generator 44 is driven.

On the other hand, the D terminal side is connected to one input of the AND gate 39, and when the D terminal is grounded, the AND gate 39
The D terminal side input of this gate 3 is set to high level.
9 is developed.

Therefore, the output pulse from pulse generator 44 is
The signal passes through an OR gate 52, which will be described later, and is input to a counter 56, which causes an up-down counter 63 to count down.

The output of the up-down counter 63 is input to the Y driver 65, and therefore, depending on the count of the counter 63, the display point is moved in the Y-axis direction to the minus side.

In this way, by appropriately operating the changeover switch 48, the display point can be moved to manual mode.

The changeover switch 49 is used to manually move the display point in the X direction, and is similar to the operation changeover switch 48.

The pulse starter 44 is the step pulse generator 2 of FIG.
However, in the embodiment of the present invention, in combination with the distance determination circuit 42, the basic display unit on the display device 50 (10 m if the grid spacing of the display device is 1/10,000 and the map is displayed is 10 m).
) is further divided into smaller distances to output step pulses.

For example, in the example in parentheses above, the unit distance Ion
is further divided into four equal parts, and a pulse signal is output every 25 m.

The counters 55, 56, 57, and 58 are for counting the number of subdivided step pulses necessary for the basic display unit shift of the display point on the display device 50, and in the above example, a quaternary counter is used. , counts up by 1 based on the count of four output pulses from the pulse generator 44, drives the up-down counters 63 and 64, and moves the display point by one step via the Y driver 65 and the X driver 66. Let's do it.

The output of the direction sensor 3 is obtained by grouping the light receiving elements at the same position on the X and Y axes, and
, 31,...37.

Therefore, except for the light receiving elements on the X and Y axes, all outputs are input to the two AND gates, and the
, specify the position on the Y coordinate.

The output of each light receiving element group that is now input to the AND gates 30, 32, 34 and 36 is directly input to the counters 55, 56, 57, 5B via the OR gates 51, 52, 53 and 54.
is input, but and game-1-31, 33, 35
The output of each light-receiving element group input to 37 and 37 is input to a binary counter, and then input to a quaternary counter via an intervening OR gate.

59, 60, 61 and 62 indicate binary counters for this purpose.

The output of the binary counter 59, the output of the AND gate 30, and the output of the AND gate 38 for manual driving of the display point are introduced into the OR gate 51.
Therefore, counter 55 is driven by any of these outputs.

The same applies to the OR gates 52, 53, and 54.

Now, each of the above binary counters 59, 60, 61 and 62 is
It is established for the following reasons.

That is, the light receiving elements 12, 14, 16, 18, 20, 22, 2
In 4.26, when displaying the position in the display grid,
The direction and Y direction components do not match and correspond to one half or two times, respectively.

Therefore, of these photodetector outputs, 2
The component that is 1/1, that is, either the X or Y direction component, is introduced into a binary counter and stored, and the counter calculates the number of pulses (2) necessary for the basic unit shift. After counting, one shift pulse is output as a basic unit shift signal.

At this time, the component corresponding to the basic unit in the X and Y directions is of course introduced into the quaternary counter as is.

By providing the binary counters 59, 60, 61, and 62 in this way, the problem of display point shift when the X and Y direction components do not match is solved.

67. Reference numerals 68 denote a JV double distance correction circuit and a F sound distance correction circuit, which are characteristics of the present invention, and are connected to the light receiving element groups 13, 17, 21, 25 and 1, respectively, as shown in FIG.
It operates by detecting any of the outputs 2, 14, 16, 18, 20, 22, 24, and 26, and the outputs ■ and ■ are introduced into the distance judgment correction circuit 42 and output from the circuit 42.
The period of trigger signal generation by the pulse generator 44 is corrected to be fi times or 71 times.

Distance judgment correction circuit 4 including both correction circuits 67 and 68
The details of 2 are shown in FIG.

FIG. 5 shows another embodiment of the circuit shown in FIG. 4, and particularly shows only the differences from the circuit shown in FIG.

The feature of this embodiment is that the binary counters 59, 60 and 61, 62 in the circuit shown in FIG.
The up-down counters 63, 64 for driving the X drivers 65, 66 are replaced by quaternary up-down counters 71, γ2, and the quaternary counters 55, 56 are omitted.

The reason for this configuration is as follows.

In the circuit shown in FIG. 4, for example, after the counter 55 has counted three pulses, the traveling direction of the vehicle suddenly changes, an output is generated to the light receiving element 20, etc., and the counter 56 starts counting. The contents of 55 are held as a display error until the vehicle returns to its original traveling direction and a pulse is input to the counter 55.

However, as shown in FIG. 5, the counter 55. If 56 is omitted and a quaternary up/down counter 71 or 72 is used, this inconvenience will not occur, and the next count in the down direction will be superimposed on the three counts in the up direction, resulting in a more accurate position display. I can do it.

The binary up/down counter 69 substituted for the counters 59 and 60 also reduces display errors for the same reason.

FIG. 6 is a block diagram showing one embodiment of the distance determination correction circuit 42.

With reference to this figure, the mechanism of generating basic shift pulses and distance-corrected shift pulses in the pulse generator 44 will be explained.

In FIG. 6, 80 is a rotation deriving device such as a flexible wire, which derives the rotation of the axle to a converter 81.

The converter 81 converts the rotation of the vehicle into an electrical signal.
Outputs a pulse signal every certain rotation of the vehicle.

This pulse signal is sent to the distance judgment correction circuit 4 in FIG.
This is the trip make output input to 4.

82 is, for example, a 4-digit decimal counter, and converter 81
Accumulate the number of output pulses.

Therefore, the count number of the counter 82 corresponds to the distance traveled.

83 is a 16-bit shift register, for example, which manually inputs the outputs of each stage of the counter 82 in parallel.

The output of this shift register 83 becomes one input of an exclusive OR circuit 84.

In addition, the other input of the exclusive OR circuit 84 is
The output of the 16-bit X register 85 is connected.

A register 86 constitutes a 16-bit Y register together with a 4-bit one-digit register 87, and its output is circulated together with the X register 85.

Reference numeral 88 is a key input section, and 89 is an encoder that converts a key-in signal from the key input section 88 into a BC code.

The output of encoder 89 is arranged to be introduced into X register 85 and control memory 90.

The control memory 90 stores a program for operating the device in predetermined steps.

This program will be explained later in the explanation of its operation.

Reference numeral 91 denotes a data memory which stores a basic scale factor, a conversion factor for generating step pulses for this basic scale factor, and furthermore, an error correction value due to the direction of automatic movement, JS. In the example, correction values for tires such as a, 2, etc., or for differences in tire diameter depending on the vehicle model are stored.

92 is an arithmetic circuit that performs arithmetic processing on the contents of the X register and Y register, and 93 is a conditional flip-flop that specifies the type of operation to the arithmetic circuit 92.

94 is a flip-flop controlled by the output of exclusive OR circuit 84; 95 is flip-flop 9;
4 and a predetermined output of the control memory 90 as inputs.

96.97 is the light receiving element group 13, 17, 21, 25 and 12, 14, 16.1B in the direction sensor 3.
, 20, 22, 24, 26 into the data memory 91,
The output of the pulse generator 44 is used as one input, and the output of the direction sensor 3 is introduced into the data memory 91 in synchronization with the generation of the pulse.

Furthermore, depending on the input of this direction sensor 3, the data memory 9
1 is loaded and outputs a conversion factor for distance correction of fi,"42.

The distance correction circuits 67 and 68 shown in FIG. It corresponds to the output signals of gates 96 and 97.

Furthermore, in FIG. 6, 98 is a decoder, and 99 is a menu link display, which displays the output of the one-digit register 87.

100 is a timing pulse generator, which is appropriately connected to this circuit and provides a predetermined timing signal.

The distance judgment correction circuit 42 is constructed as described above. Next, the operation of this circuit will be explained. reveal the mechanism of

First, the scale factor of the map is inputted from the key input section 88.

For example, if you are using a 1/10,000 scale map, key in 100.

This is done for convenience, as the minimum unit of most general maps is up to the hundredth place, and it is also possible to key in I 0000 if necessary.

At this time, the key-in signal is sent to the encoder 89, and the BCD
Each signal to be converted into a signal and further scaled is the timing signal t1 to t4 from the timing generator 100.
T1 to T4 are used.

The key-in signal converted into a BCD signal by the encoder 89 is serially input to the X register 85.

Now input the scale factor from the key human power section 88 with a minimum unit of 10.
Since the 0th position is set, if the X register 85 is set to 4' digits of 4 bits each, a maximum scale factor of 1/999,900 can be input, which is usually sufficient for maps in general use.

Next, a start signal is introduced from the key human power section 88.

The only operations to be performed on the key manual section 88 are the input of the scale factor and the start signal.

The start signal is converted into a BCD signal by the encoder 89, and then introduced into the control memory 90, where a program specifying the operation of this circuit is executed.

First, as a first step, "1 0 0" stored in the X register 85 is transferred to the Y register 86 (including the 1-digit register 87).

At the same time, the control memory 90 loads the data memory 91 and puts a basic scale factor of 100 (actually 10,000, but since the minimum unit for keying in is 100) into the X register 85.

Therefore, in this step, the X and Y registers also have "100".
has been entered.

As a second step, the control memory 90 sets the conditional flip-flop 93 to division mode, and the arithmetic circuit 92 divides the contents of the X register and the contents of the Y register. =1 is input to the X register 85.

Therefore, at this point, "1" is stored in the X register 85 and "'100" is stored in the Y register 86.

As the third step, the content "1" of the X register 85 is transferred to the Y register 86, and the X register 85 is stored with a conversion coefficient (the basic step pulse is The number of pulses necessary to generate from 44 (here, 16) is derived from the data memory 91 and input.

As a fourth step, conditional flip-flop 93 is set to multiplication mode, and the contents of X register 85 and Y register 86 are multiplied.

The product is input to the X register g5 in the same way as in the case of division.

In this way, the basic pulse number for the input scale factor is determined.

In this case, it is "16".

At this time, "'1" remains in the Y register 86.

Since it is necessary to display the scale factor keyed in here, the basic scale factor "100" is read from the data memory 91.
is taken out, introduced directly into the arithmetic circuit 92, and inputted into the Y register 8.
6 is multiplied by the content ""1'' to obtain the original input scale factor and input it to the Y register 86.

As mentioned above, the 1-digit register 87 is made up of 4 pits, so if it is circulated in synchronization with the digit signals T1 to T4,
On the numerical display 98 it is possible to display a dynamic scale ratio.

This display method is well known.

At the end of the fourth step, "16" is input to the X register 85 and "100" is input to the Y register 86.

If the car is started from this point, a minimum unit distance signal is inputted to the counter 82 in time series from the converter 81 according to the distance traveled.

Since the contents of the counter 82 are input to the shift register 83 separately, the shift register 83 and the X register 85
By circulating once for each pulse input from the converter 81, the exclusive OR circuit 84 can detect whether the contents of the counter '82 and the contents of the X register 85 match.

That is, when the car travels a distance corresponding to the basic display interval, the content of the counter 82 becomes 16 in this example, and X
When a match is found with the contents of the register 85, a low L signal is output from the exclusive OR circuit.

For example, if the input scale rate is 1/20,000, "3 2" is stored in the X register 85, and therefore, unless the contents of the counter 82 become "3 2", the exclusive There is no low signal output from the OR circuit 84.

When the travel distance of the vehicle required to generate the basic step pulse is detected as described above, this detection signal, that is, the low level output signal of the exclusive OR circuit 84 is
The flip-flop 94 is inverted and its output is set to high level.

Therefore, when a determination signal is output from the control memory 90 at this time, the AND gate 95 opens and the pulse generator 44
to generate a basic step pulse.

The low output signal of the exclusive OR circuit 84 is also input to the reset terminal of the counter 82 and resets the counter 82.

Therefore, when the car travels further and there is a pulse output from the converter 81, this pulse is newly accumulated in the counter 82, and after counting ``6'' again, the pulse is sent to the X register 85.
The output of the exclusive OR circuit 84 is set to low level, and the pulse generator 44 is similarly triggered to generate a second step pulse.

At the same time, the counter 82 is also reset again to prepare for the next pulse count.

Note that while the contents of the counter 82 and the contents of the Even if a determination signal is output from 90, AND gate 95 remains closed, so no step pulse is generated.

If there is no output from a predetermined light receiving element in the direction sensor 3, the basic step pulse is generated from the pulse generator 44 as described above, but if the AND gate 96 or 97 is opened by the output of the one-way direction sensor 3. , the data memory 91 is loaded by the output of this AND gate, and outputs the conversion coefficient obtained by multiplying Vl or y to the X.jita.2 85.

In the above example, this value is /T 16x, ff or 16x -.

However, when inputting to the X register 2 register 85, there are four or five decimal places; for example, if it is 16X, /T, it is input as "23".

Therefore, in the exclusive OR circuit 84, there is no output until the content of the counter 82 reaches "23".
Only then does the pulse generator 44 output a shift pulse.

This count number "23" corresponds to the basic actual running distance of the vehicle when traveling in the diagonal direction.

In this circuit, as described above, the generation timing (period) of the step pulse generated from the pulse generator 44 is appropriately corrected based on the output of the direction sensor 3.

The apparatus of the present invention has the above-mentioned structure, and the operation thereof will now be explained with reference to a specific example of position display of the apparatus of the present invention, with reference to the embodiment circuit shown in FIG. 4 above.

7A shows an example of a vehicle traveling on a road, and FIG. 7B shows an example of tracing on the display device 50 in this example of travel.

The thick line frame in Figure a is a virtual line every lOm corresponding to the display grid on the display device 50 (shown in Figure b).

The thin lines are virtual lines every 2.5 m.

The display grid in FIG. b is formed, for example, at intervals of 1, and when a 1/10,000 scale map is used, one grid interval indicates a travel of IOm.

First, in FIG. 4, selector switch 48 for position adjustment.
49 to the contacts U, D, R, and L as appropriate to move the display point to the start point a (shown in Figure b).

This starting point a corresponds to point A on the map in Figure a.

That is, when both the changeover switches 48 and 49 are appropriately switched to the U, D side or the R, L side, the OR gate 47 is opened, and the low frequency pulse from the low frequency oscillator 46 is transmitted via the AND gate 45 and the OR gate 43. It is introduced into the pulse generator 44 and triggers it.

Therefore, a low frequency pulse is output from the pulse generator 44 and input to the AND gate groups 30, 31, . . . , 41.

On the other hand, by the appropriate switching of the changeover switches 48 and 49, one of the AND gates 38 and 39 and one of the AND gates 40 and 41 is opened, and the low frequency pulse from the pulse generator 44 is applied to the AND gates 38 and 39. .

The Y driver 65 and the X driver 66 are driven by the outputs of the up-down counters 63 and 64, and the display point is moved to the start position a.

In this way, the display point is set at a predetermined position by appropriately operating the changeover switches 48, 49, and the vehicle is started from this point.

First, as shown in FIG. 7a, at the starting position A, the direction of travel of the vehicle is north.

Therefore, the magnetic needle is on the light receiving element 11, and an input is generated to the AND gate 30 in the circuit shown in FIG.

Now, the AND gate groups 30 to 41 have a pulse output from the pulse generator 44 when the vehicle travels every 2.5 m, and the changeover switches 48 and 49 are set to the steady position shown in the figure. When there is an output from the direction sensor, the AND gate to which this output is introduced into the input opens or
The pulse output from pulse generator 44 is derived.

That is, from point A to point B, the AND gate 30 is opened depending on the output of the light receiving element 11, so the quaternary counter 55 counts up 4, and the up/down counter 6
Input one pulse per 3.

As a result, one Y driver 65 is driven in the ten direction of the Y axis, and the display point on the display device 50 is shifted from point a to point b.

Furthermore, since the direction is the same until point C in Figure a, the quaternary counter 55 further counts 1.

Even after reaching point C, the direction of travel is still north, so the counter 55 counts 2.

However, when it reached point D, the vehicle was heading east-northeast, so the direction sensor sent an output to the light receiving element 24, and the AND gates 31 and 34 opened, and the 1x distance correction was made. The circuit 68 is driven 52 and outputs a single distance correction signal (2).

52 Distance judgment correction circuit 2 for this single distance correction signal ■
5. Depending on the human input to 42, the pulse generator 44 outputs the next pulse at a period of 12 times, so that at point E, where the vehicle has traveled (2.5 X -) m from point DV, Andgame-1-31. At 34 there is a pulse input from a pulse generator 44 .

The traveling distance in the Y direction from point D to point E is detected by the AND gate 31 and inputted to the binary counter 59, and by the count of two pulses of the counter 59, it is passed through the OR gate 51 and converted into a quaternary value. One pulse is introduced into the counter 55.

On the other hand, the output of the AND gate 34, which detects a certain distance traveled in the X direction, is directly input to the quaternary counter 57 via the OR gate 59.

Therefore, when point E is reached, there is one pulse input to the counter 57 and no pulse input to the counter 55.

When reaching point F from point E, 1 is added to counter 57 in the same way.
There are 2 pulse inputs, and their contents are 2.

At the same time, since there is an input to the binary counter 59, the counter 59 counts up and the quaternary counter 55 has 1.
As a result, the contents of the counter 55 become 3.

At point G, which is further advanced two steps in the same direction, the counter 55 receives one pulse input and the counter 57 receives two pulse inputs, and as a result both counters 55 and 57 receive one pulse input. A pulse is issued to drive up-down counters 63 and 64, and the display point is moved from point b to point g.

During the next run from point G to point H, the counter 57 counts four input pulses and outputs one pulse, drives the up-down counter 64, and changes the display point. Shift by 1 step parallel to the X axis, while 4
Since the advance counter 55 has only two pulse inputs,
There is no pulse output from the counter 55, so the Y driver 65 remains undriven.

As a result, when traveling from point G to point H, the display point is point g.
Shift from to point h.

As the distance determination correction circuit 42 and pulse generator 44 continue to travel northward, the distance judgment correction circuit 42 returns to the steady state of outputting a pulse every 2.5 m, and the counter 55 starts counting up. Since this count-up is superimposed on the "2" that was counted up in the counter 55 when the point was running, the counter 55 outputs an output at the point ■, drives the up-down counter 63 by one step, and sets the displayed point. Shift from h to point i.

Similarly, as the vehicle progresses, the display device 50 displays the following information:
The direction of travel is tracked.

In Fig. 7b, the trajectory connecting each point shows the shift relationship of the display points, and the actual traveling trajectory of the vehicle is displayed overlapping the trajectory of the above display points to show the degree of coincidence. .

Although it does not appear in Figure 7, if the vehicle is located in the northeast, northwest,
When proceeding in the southeast or southwest direction, the light receiving elements 3, 7,
11 and 15, and as a result, the V/T times distance correction circuit 67 is driven, and a 77 times distance correction signal A is derived to the distance determination correction circuit 42.

Therefore, the pulse-to-signal interval output from the pulse generator 44 is every (2.5 x -, IT) m.

At this time, since the distances in the X and Y directions are equal, there is no need to provide a binary counter to match the distances in the X and Y directions, as in the case of traveling in the north-northeast direction described above.

In the above-described embodiment, the pulse generator 44 generates a pulse every 1/4 of the unit shift distance of the display point in order to prevent errors caused by zigzag movement as much as possible. Such a method is particularly effective, for example, when the scale of the map is large and the resolution of the display device 50 is poor.

Further, in the above-described embodiment, a case was shown in which a magnetic needle was used as the direction sensor 3, but it goes without saying that a magnetically sensitive element such as a Hall element may also be used.

Rather, it is preferable to use a Hall element rather than a magnetic needle on a moving object.

As described above in detail with reference to the embodiments, the device of the present invention determines the timing of unit pulse generation for driving the display device when traveling in a direction other than east, west, south, or north based on the direction information from the direction sensor. This correction eliminates display errors when the vehicle is running diagonally, making it possible to more accurately track the progress of the vehicle.

This device can also be used for creating maps by attaching a plotter to the display section.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional device of the present invention, and FIG.
The figures are an explanatory diagram of the operation of the device shown in Fig. 1, Fig. 3 is a diagram of the structure of the direction sensor, Fig. 4 is a main logic circuit diagram of an embodiment of the present invention, and Fig. 5 is a diagram of another embodiment of the present invention. 6 is a logic circuit diagram embodying a part of the logic circuit shown in FIG. 4 shown in blocks; FIG. 7 is used to explain the operation of the device of the present invention. It is a diagram. 5... Direction sensor, 43... Distance judgment correction circuit, 44... Pulse generator, 50...
...Display device, 65, 66...X, Y driver, 6 7. 6 8...--Distance correction circuit.

Claims (1)

[Scope of Claims] 1. A display device on which a road map is placed and displays the vehicle position in accordance with the road map, a means for detecting the traveling direction of the vehicle, and a distance detecting device that generates a step pulse every time the vehicle travels a certain distance. a detecting means; and a display device for counting the step pulses corresponding to the X and Y directions of the display device according to the traveling direction detection output of the vehicle, and displaying the current position while the vehicle is traveling based on the counted contents. and display driving means for driving the display device, and means for correcting the cycle of step pulse generation according to the detection output of the traveling direction detecting means in a direction diagonal to the X and Y directions of the display device. Vehicle position display device.