JPS58221111A - Display for position on vehicle - Google Patents

Abstract

PURPOSE:To enable the visual announcement of the positional relation between a vehicle and an obstruction to the driver by controlling a measuring means for distance and a two-dimensional display means. CONSTITUTION:A system controlling unit SCU controls a measuring means ODC including an ultrasonic transmitter and receiver 20 and 30, and a two-dimensional display means EDU. The information corresponding to the distance between a vehicle and an obstruction measured with the means ODU is displayed on the means EDU, and the display information of the means EDU is updated and displayed on the different display coordinates at the prescribed timings corresponding to the speed of the vehicle, whereby the positional relation between the vehicle and the obstruction is displayed on the two-dimensional coordinates.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an on-vehicle position display device, and more particularly to an on-vehicle position display device that displays the positional relationship between a vehicle and obstacles existing near the vehicle on two-dimensional coordinates.

When driving a vehicle, if there is an obstacle in the driver's blind spot, such as behind a part of the vehicle, the driver will be able to avoid the obstacle even if it is very close to the vehicle. It's hard to notice. Accidents are likely to occur in such cases. For example, when a vehicle with a steering wheel on the right side turns left, if a bicycle, two-axle vehicle, etc. is present in a position that cannot be seen from the window on the left side of the vehicle body, a so-called entanglement accident is likely to occur.

In addition, when parking a vehicle, if the space available for parking is narrow and the distance between the vehicle and other vehicles, walls, etc. is narrow, if a driver with little driving experience is driving the vehicle, the vehicle body may hit an obstacle. Probability is high. Furthermore, even for drivers with a lot of driving experience, situations like the second one place a considerable psychological burden on them.

Therefore, there is a need for a device that allows the driver to know the distance between the vehicle and obstacles in the blind spot. Conventionally, such devices are known that measure the distance between a vehicle and an obstacle using ultrasonic waves or the like, and issue an alarm using a buzzer or the like when the distance gets closer. However, since the second type of device only emits a warning sound, it is difficult for the driver to intuitively understand the positional relationship between the vehicle body and the obstacle. For example, with this type of device, the driver does not know which part of the vehicle the obstacle is closest to and how far away the obstacle is from the vehicle. Therefore, when this type of device is installed in a vehicle, the driver must either slow down the vehicle or stop the vehicle and check the surroundings of the vehicle when the alarm sounds. In other words,
The second type of device does not provide much assistance to the driver.

A first object of the present invention is to provide an on-vehicle position display device that allows a driver to visually know the positional relationship between the vehicle and obstacles, and a second purpose is to provide an on-vehicle position display device that allows a driver to visually know the positional relationship between the vehicle and obstacles. The second purpose is to provide an on-vehicle position display device that provides an indication, and the third purpose is to provide a two-position display device that issues an alarm when the vehicle and an obstacle are in a dangerous positional relationship. That's true.

In order to achieve the following objects, the present invention aims to achieve the following objects.

A distance measuring means and a two-dimensional display means are provided, and information corresponding to the distance between the vehicle and the obstacle measured by the distance measuring means is displayed on the two-dimensional display means, and at a predetermined timing according to the speed of the vehicle. The display information of the dimensional display means is updated and displayed at different display coordinates, and the positional relationship between the vehicle and the obstacle is displayed on the two-dimensional coordinates. According to this, the driver can reliably know the positional relationship between any part of the vehicle and the obstacle on two-dimensional coordinates, and can also visually check the vehicle speed information at the same time as the obstacle. As a result, when the distance between an obstacle and the vehicle approaches, the driver can take optimal action according to the information displayed on the device without visually checking the actual obstacle.

In other words, even if an obstacle exists in a blind spot, the driver can easily drive to avoid the obstacle.

In one preferred embodiment of the present invention, the position detecting means is an ultrasonic transmitting element and an ultrasonic receiving element, and these distance detecting elements are provided at the front and rear sides of the vehicle, respectively, so that when the vehicle moves forward, , the distance information obtained by the detection element at the front side of the vehicle is used, and when the vehicle moves backward, the distance information obtained by the detection element at the rear side of the vehicle is used.

As a result, the latest obstacle information in the vehicle's direction of travel can always be obtained.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 1a shows the appearance of an automobile equipped with the on-vehicle position display device of the embodiment, and FIG. 1b shows the appearance of the driver's seat of the automobile. Referring to FIGS. 1a and 1b, ultrasonic transmitters 20a are provided in the front bumper 1 and rear bumper 2 of the vehicle, respectively.

30a and ultrasound receivers 20b and 30b are attached. A display EL, that is, a two-dimensional display means, is arranged on the driver's seat panel at a position visible to the driver. As will be explained in detail later, this display EL is constructed by two-dimensionally arranging a large number of electroluminescent display elements.

The second display EL displays a large number of vertical lines indicating the shape of the vehicle and the position of obstacles.

FIG. 2 shows the system configuration of the on-vehicle position display device mounted on the automobiles shown in FIGS. 1a and 1b.

This will be explained with reference to FIG. The ultrasonic transmitter 20a
, 30a and the ultrasonic receivers 20b, 30b are each connected to an obstacle detection unit ODU. Briefly, the obstacle detection unit ODU emits ultrasonic waves in a predetermined direction from the ultrasonic transmitters 20a and 30a, detects the ultrasonic waves with an ultrasonic receiver oriented in the same direction, and detects an obstacle. The distance between the obstacle and the ultrasonic transmitter 20a is determined from the time required for the reflected wave to arrive when an object is present.
, 30a and the ultrasonic receivers 20b, 30b, and send the measurement results to the system control unit SCU.
Send to. In this embodiment, the system control unit SCU is composed of a microcomputer as will be described later. This system control unit SCU includes
In addition to the obstacle detection unit ODU, the vehicle speed detection unit V
D.U.

A starting port MSTC, a direction detection circuit DDC, a display control unit DCU, and a sound generation unit VGU are connected. The display control unit DCU includes the display E
It is connected to an EL display unit EDU including L.

FIG. 3a shows a schematic configuration of the obstacle detection unit ODU. This will be explained with reference to FIG. 3a. Said ultrasonic transmitter 2
0a and 30a are drive circuits 50 and 70, respectively.
are connected to the output ends of the ultrasonic receivers 20b and 30b, respectively, and discriminator circuits 60 and 80 are connected to the output ends of the ultrasonic receivers 20b and 30b, respectively.
is connected. The drive circuits 50 and 70 and the discrimination surface [
60 and 80 are microcomputers 90, respectively.
It is connected to the. The microcomputer 90 used in this embodiment is an 8-bit single-chip microcomputer 8748 manufactured by Intel Corporation. 90a is a crystal oscillator for generating clock pulses which are the basis of the operation of the microcomputer. An 8-bit output port of microcomputer 90 is connected to system control unit SCU.

8- FIG. 3b shows a specific configuration of the drive circuit 50 shown in FIG. 3a. Note that in FIG. 3a, the drive circuits HI30 and HI70 have the same configuration, so a description of the structure of the drive circuit 70 will be omitted. This will be explained with reference to FIG. 3b. 51 is a pulse oscillator constructed using an integrated circuit, and always outputs a pulse signal with a duty of 50% and a frequency of 40 KHz. The output signal of the pulse oscillator 51 is transmitted through the Nandt gate 52.
The signal is applied via an inverter 53 to a power amplification circuit 54 composed of two transistors. One input end of the Nant gate 52 is connected to the output port of the microcomputer 90, and when the output level of that port is at a high level H, a pulse signal from the pulse oscillator 51 is generated at the output end of the Nant gate 52. . A voltage vb of 12V from the battery is applied to the power amplifier circuit 54, and a pulse signal having an amplitude of 12V appears at the output terminal of the power amplifier circuit 54. The output terminal of the power amplifier circuit 54 is connected to the primary side of the step-up transformer T, and when a pulse signal is applied to the primary side of the transformer T, a signal with an amplitude of about 100 V is generated on the secondary side. . This boosted 40Kl (z
is applied to the ultrasonic transmitter 20a.

FIG. 3c shows a specific configuration of the discrimination port @60 shown in FIG. 3a. It should be noted that since the discrimination circuits 60 and 80 have the same configuration, it is a discrimination port! The explanation of l1r80 will be omitted.

This will be explained with reference to FIG. 3c. The ultrasonic receiver 20b is
It is connected to the amplifier circuit 61 of the discrimination circuit 60. The amplifier circuit 61 includes three stages of cascaded narrowband amplifiers A.
t, A2 and A3. Each amplifier AI,
A2 and A3 are inverting amplifiers each composed of an operational amplifier, and each feedback path has a frequency of 40KHz.
A parallel resonant circuit consisting of a resonant capacitor and an electric coil is connected.

62 is a variable gain amplifier. This variable gain amplifier 62 is composed of an operational amplifier 62a, an analog switch (analog multiplexer) AS, and a large number of resistors. The analog switch AS used here is CMO5MSI MCI4051 manufactured by Motorola. To briefly explain the variable gain amplifier 62, the second circuit connects the 3-bit control input terminal co of the analog switch AS.
, ci and C2.
A resistor selected according to the signal from 0 is connected to the operational amplifier 62a as a feedback resistor, and the signal is amplified with an amplification degree determined by the resistor and the input resistance rin. In other words, the amplification degree G of this circuit 62 is determined by the combined resistance of the feedback resistors connected between the inverting input terminal and the output terminal of the operational amplifier 62a.
If t, it is expressed by the following formula.

G=-rt/rin... (I) Analog switch AS is connected to its boats XO and XI.

X2. X3. . For example, if the data of the gain setting signal is different for the input terminals GO, CI and C2,
And if it is "0" which is L, port xO is selected and the combined resistance rt becomes rO, so the gain G is -
rO/rin. Similarly, the data of the gain setting signal is rl, 1. r2”.

When r3J, r4J, r5J, r6J and "7", ports XI, X2. X3. X
, 4°×5. X6 and X7 are selected and the combined resistance rt
are rO, ro+r1., respectively. , rO+rl+r2
．． rO+rl+r2+r3. rO-1-rl +r2
+r3+r4. ro+rl+r2+r3+r4+r5
．． rO+r1. +r2+r3+r4+r5+r6 and ro+rl+r2+r3+r4+r5+r6+r7. Therefore, the gain G of the variable gain amplifier 62 is set in eight stages by the gain setting signal. In this embodiment, the maximum gain when the gain setting signal data is "7" is set to about 128 times the minimum gain when the gain setting signal data is "0".

63 is an inverting amplifier, 64 is a rectifying and smoothing circuit, and 65 is a comparator. A reference voltage Vr obtained by dividing the voltage vb by a resistor is applied to one input terminal of the comparator 65, and a DC voltage Vs obtained by the rectifying and smoothing circuit 64 is applied to the other input terminal of the comparator 65. has been done. 66 is a level conversion circuit, that is, an interface circuit 12, the output terminal of which is connected to the microcomputer 9.
Connected to 0. Voltage VCC is 5v.

The general operation of the obstacle detection device will be explained. The second device emits ultrasonic waves from the left ends of the front bumper 1 and rear bumper 2 toward the left side of the vehicle, so if there is an obstacle, the ultrasonic waves reflected by the obstacle will be reflected by the ultrasonic receiver. This is detected by the electrical circuit to detect the presence of an obstruction.

In reflective obstacle detection using ultrasonic waves, the intensity of reflected waves varies greatly depending on the location of the obstacle, and if the detection sensitivity is too high, even objects that are not obstacles may be detected as obstacles. Also, there is a reflected wave that reaches the receiver after being reflected multiple times, and if this reflected wave is detected and the distance is calculated.

This will cause a large error. Therefore, in this embodiment,
The area to be detected is divided into multiple areas based on distance, and different sensitivities are set for each area.
High reliability is achieved by setting a time window and regulating the time for detecting obstacles. Specifically, the sensitivity is set by changing the data of the gain setting signal that sets the analog switch As. Furthermore, the time is determined by changing the reference data to be compared with the data counted by the interval timer inside the microcomputer 90.

Table 1 below shows the relationship between the data D g of the gain setting signal in each region, the reflected wave detection inhibition period data ΔTinh, and the detection end time data Tgmax.

In Table 1, the numbers marked with the alphabet ■ are as follows:
It is shown in hexadecimal notation. Values within 0 are decimal numbers. The data in Table 1 is stored in advance in a ROM (read-only memory) within the microcomputer 90. The value 1 for the time data ΔTinh and Tgmax shown in Table 1 corresponds to a time of 80 μs in the second embodiment.

FIG. 4 shows the configuration of the system control unit.

This will be explained with reference to FIG. To briefly describe the system control unit 15-SCU, this unit is composed of a microprocessor 200 and its peripheral circuits. The microprocessor 200 used in this unit is
This is the Z80 sold by Zilog and others. 201 is a pulse generator that supplies clock pulses to the microprocessor 200. The microprocessor 200 and display control unit DCU include a decoder DEL and a buffer BF.
I.

BF2. They are connected via a bidirectional buffer BDB or the like. Further, an I10 interface PPI is connected to the microprocessor 200.

This I10 interface PPT is Intel's 8
It is 255. Note that the microcomputer 200 and I10 interface PPI have address designation terminals A, I5 to AO and data input/output terminals D7 to DO.
For other terminals, the signals are valid when the level is low (low active). The chip select end of the PPI contains the lower address 8 bits A7 to A of the microprocessor 200.
An AND (OR) signal of the output signal of the decoder DE2 connected to I'10 and the I'10 selection signal selection signal -16RQ is applied.

I10 interface PPI boat PA7~PAO
is connected to the voice generating unit VGU. PPI's boats PB7 to PBO are the aforementioned obstacle detection units OD.
Connected to U.

The direction detection circuit DDC is connected to the PPI boats PC2 to PCO. The switch SWI included in the direction detection circuit DDC is a detector that operates in conjunction with the shift lever of the automobile, and it has three switches that close depending on the state of the shift lever: forward (neutral), stop (neutral), and reverse. It has a contact point. Each of these contacts is P
It is connected to input ports PC2, Pct and PCO of PI. Startup time @STC is PPI input port PC
Connected to 3. The starting circuit STC is the starting switch S
It consists of W2 and a waveform shaping circuit. Start switch S
W2 is of a self-resetting type and has a normally open contact. Switch SW2 is located at the driver's seat.

The vehicle speed detection unit VDU has a microprocessor 200
is connected to the external interrupt terminal INT. The vehicle speed detection unit VDU includes a rotor RT having magnetic poles around it connected to a speedometer cable, and a magnetic? It has general detection means for detecting rotation using an electric coil CL to be detected. The output signal of the electric coil CL is applied to the microprocessor 200 via a waveform training circuit and a branching unit.

FIG. 5 shows the configuration of the display control unit DCU and the EL display unit EDU. This will be explained with reference to FIG. The EL display unit EDU used in this embodiment is S-102LA made by Sharp Electric, and the display control unit DCU is S-1026F, also made by Sharp Electric. S-1
021A is a display unit using an electroluminescent display panel 1. This display panel has display elements horizontally 320. They are arranged in a 240-vertical matrix. This EL display unit EDU includes an EL display panel, a scanning drive circuit for the EL panel, and a logic circuit controlled by an external signal. EL display unit EDU is a data signal.

It operates in response to a data transfer lock signal, horizontal synchronization signal, and vertical synchronization signal.

The EL display unit EDU is a cathode ray tube display.
Power supply voltages of 5V, 30V and 200V are applied to U2.

S-1026F is a full graphic display control unit dedicated to display unit S-1021A.

S-1026F, that is, the display control unit DCU is C
It has an RT controller, pixel memory, multiplexer, etc. The pixel memory is an 8-bit random access memory RAM with a storage capacity of 9600 bytes. The contents of this pixel memory are controlled by control signals output from the CRT controller in the EL display unit E.
The 8-bit data is read out periodically at a predetermined timing according to the scanning timing of the DU, and the read 8-bit data is converted from parallel to serial and sent to the EL display unit ED.
Sent to Tl. In addition, when there is a read or write request from a device connected to the display 19-control unit DCU, the pixel memory switches the signal path using a multiplexer to select the device that made the request, that is, the number of this implementation side.
It is connected to the system control unit SCU. Regarding this switching of the signal path, it is possible to select which of the read requests according to the read timing of the EL display unit EDU and the read or write requests from the system control unit SCU should be given priority.

FIG. 6 shows the configuration of the voice generating unit VGU.

This will be explained with reference to FIG. Briefly speaking, this sound generation unit sequentially reads out digital data corresponding to sound stored in a read-only memory ROM in response to commands from the system control unit SCU, converts it into an analog signal, and converts it into a predetermined signal. This is a device that outputs audio from a speaker SP. This unit uses a microprocessor 300 as a control circuit, and its system bus includes a memory ROM1 that stores the operating program of the microprocessor 300 itself, and a memory ROM2 that stores audio data 20. ROM3 and ROM4
is connected. The microprocessor 300 used in this embodiment is an Intel 8085. The microprocessor 300 has an I10 interface IOI
It is connected to the system control unit SCU via.

7a and 7b show the operation of the microcomputer 90, that is, the operation of the obstacle detection unit ODU.

FIG. 7a shows the main routine, and FIG. 7b shows the obstacle detection processing routine.

First, the general operation of the obstacle detection unit ODU will be described with reference to FIG. 7a. First, step S1 is executed to initialize. This is the RA inside the microcomputer 90.
Predetermined data is written in M (random access memory) and the level of each output port of the microcomputer is set to the initial level. That is, the ports controlling the energization of the drive circuits 50 and 70 are each set to a low level L, and output data indicating that there is no obstruction at the port connected to the system control unit.

The microcomputer 90 then proceeds to step 82 and stores the value "2" in register N.

This value is used for selecting the ultrasound transmitter and ultrasound receiver to be used. The number 2 indicates that the ultrasonic transmitter 30a and ultrasonic receiver 30b provided at the rear of the vehicle are used, and the number l indicates that the ultrasonic transmitter 20a and ultrasonic receiver 20b provided at the front of the vehicle are used. shows.

The microcomputer 90 then proceeds to step S3 and executes an obstacle detection subroutine. The obstacle detection subroutine will be explained in detail later, but in brief, a selected ultrasonic transmitter emits an ultrasonic wave, and a selected ultrasonic receiver hits an obstacle and returns the ultrasonic wave. That is, the presence or absence of a reflected wave is detected, the distance between the vehicle and the obstacle is calculated according to the time required from the emission of the ultrasonic wave to the reception of the reflected wave, and the result is stored in a predetermined register. When no obstacle is detected, "0" is stored in that register.

When the microcomputer 90 proceeds to step S4, it decrements the contents of the register N, that is, minus 1.

Next, the process advances to step S5, and the contents of register N are checked. If the content is "0", the process advances to step S2; otherwise, the process advances to step S3.

Step 82. Through the processing in S4 and S5, the contents of register N become 0, 1, or 2. When the contents of register N are 1 and 2, an obstacle detection subroutine is executed. That is, the microcomputer 90 repeatedly performs a process of alternately detecting obstacles at the front and rear of the vehicle.

Next, the obstacle detection subroutine will be explained with reference to FIG. 7b. First, the microcomputer 90 performs step S6.
1, the gain setting signal is set to "0" and the amplification degree of the variable gain amplifier 62 is set to the lowest level "0".

Next, the process advances to step 862, where the microcomputer 90
is the ultrasonic transmitter 20 according to the contents of the register N.
Select a or 30a and send 80μs to the boat connected to one of the Nantes gates 52.
A high level H is output during the period. As a result, Nantes Gate 5
A 40KHz pulse signal from the pulse generator 51 is generated at the output end of 2 for the duration of its high level, which energizes the ultrasonic transmitters 20a and 30a, and the 40K
A Hz ultrasonic signal is emitted.

Next, the process advances to step S63, where the microcomputer 90
sets the internal interval timer to start.

In the next step S64, the microcomputer 90 reads the state of the port connected to the output terminal of the level conversion circuit 66, and selects the next step according to the result. That boat is at low level L1, i.e. V s
> When V r is at the ultrasonic detection level, step S
Proceed to step 65, and if no ultrasound is detected, proceed to step 86
Proceed to step 9.

When the microcomputer 90 detects the reflected wave and proceeds to step S65, the microcomputer 90 determines whether the time since starting the interval timer, that is, the time since emitting the ultrasonic waves, is between Tmax and T+++in. Check if. Time Tw in this process
ax and T in are the longest and shortest times set by the time data ΔT inh shown in Table 1 above, and these times are the same as those in the detection area described above, that is, the ultrasonic transmitters 20a, 30a and Ultrasonic receivers 20b, 30
This is the time during which detection of reflected waves is prohibited in order to monitor one area out of a plurality of areas divided according to the distance between b and the obstacle. For example, in Table 1, gain level/11. When setting (Dg) to 2, T wax
is 2400μS corresponding to IE old version, and Twin is 0
It is 0 μS corresponding to 01N. Then, during this time, even if a reflected wave is detected, the detection is invalidated, and the process then proceeds to step 869. If a reflected wave is detected during the period in which reflected wave detection is valid, then the process proceeds to step 866.

When the microcomputer 90 proceeds to step S69,
Check whether the time from the timer start exceeds Tgmax. This time Tgmax is the time set by the time data Tgmax shown in Table 1 above, and this time is the time when the ultrasonic waves emitted during one obstacle detection have an influence on the next obstacle detection. Set the time enough so that it does not cause any damage. For example, in a region where the gain level is set to 2, Tgmax is 2CH.
It becomes 3520 μs corresponding to . If the time does not exceed Tgmax, the process returns to step S64. Time is TgIl
If it exceeds ax, the process proceeds to step S70.

In step S70, the microcomputer 90 updates the gain setting and increases the level by one.

For example, if the gain level G is 0, then G is 1
Set to .

In the next step 871, it is checked whether the gain level G set in the previous step 870 has exceeded the maximum level, that is, 7. If G is 7 or less, the process proceeds to step 872, and if G is 8, then "No reflected wave" (for example, data 5rFFHJ) is stored in a predetermined register corresponding to register N, and the next timer reset is performed. Proceed to processing.

In step S72, the microcomputer 90 resets the interval timer, and then returns to step S62.

If a reflected wave is detected after the detection prohibition period Tll1ax has elapsed, this is processed as valid data in step 866, and the ultrasonic wave is transmitted to the ultrasonic transmitters 2°a and 30.
The time from when the ultrasonic wave is emitted at point a until the reflected wave of the ultrasonic wave is detected by the ultrasonic detectors 20b and 30b is checked from the count value of the interval timer, and this value and
The distance between the vehicle and the obstacle is calculated from the speed of the ultrasonic wave, and the result is stored in a predetermined register according to the contents of register N.

In the next step S67, the microcomputer 90 waits until the time elapses above Tgmax, and then proceeds to step 868.

In step 868, the measurement results are stored in a predetermined register corresponding to register N. In step s74, the microcomputer 9o resets the interval timer, and in step S75, outputs the value of N number - 27=value and the value of the measurement result storage memory corresponding to N, and returns to the main routine processing.

In this embodiment, the sensitivity of the obstacle detection device is changed by changing the amplification degree of the amplifier on the receiving device side, but the sensitivity can also be changed by changing the reference voltage Vr of the comparator 65, and vice versa. The sensitivity can also be changed by changing the ultrasonic transmission intensity on the transmitter side.

Next, the operation of the microprocessor 200 shown in FIG.
That is, the overall operation of the on-vehicle position display device will be explained. Before giving a detailed explanation, an outline of the operation will be explained. On the EL display panel, vertical lines indicating the shape of the vehicle and the position of obstacles are displayed as shown in FIG. Car image C
A is always displayed in the same position. The Y coordinate, that is, the vertical position where the vertical line OB appears, corresponds to the distance between the detected vehicle and the obstacle. This vertical line OB first depends on the running direction of the vehicle; for example, when the vehicle is moving forward, this vertical line OB is located on the left side of the front bumper of the image of the vehicle, that is, the position where the ultrasonic transmitter and ultrasonic receiver are located. displayed at the X coordinate of Then, the display position is sequentially updated at a cycle according to the speed of the vehicle. For example, when the vehicle moves forward, the vertical line OB sequentially moves to the left side of the display panel, that is, to the rear side of the displayed vehicle. Further, this vertical line is erased every predetermined period, and the next vertical line is newly displayed. Movement of the vertical line is processed by the microprocessor 200 by an external interrupt generated by a speed signal applied to the INT terminal, and erasure of the vertical line is processed by an interrupt generated by the count result in the internal processing of the microprocessor 200. Ru.

FIG. 9 shows the main routine of the microprocessor 200. This will be explained with reference to FIG. First, step 51
Initialization processing is performed with 00. This includes processing such as clearing the memory RAM, setting the mode of the I10 interface PPI, and initial setting the status of each port.

Microprocessor 200 starts counting an internal timer in step 101.

Next, in step 5102, an image display routine, which will be described in detail later, is executed. This subroutine is a process for displaying an image of a car.

In step 5103, the state of the start switch SW2 is read, and depending on the result, step 5104 or step 8 is read.
Proceed to step 105. If start switch SW2 is not operated,
In step 5104, interrupts are disabled and switch SW2 is
Wait until it is operated.

Microprocessor 200 enables interrupts in step 5105. In subsequent steps, when an interrupt occurs, the process being executed is interrupted and jumps to a predetermined interrupt process.

Proceeding to step 106, the microprocessor 200 selects the ports PBO to PB of the I10 interface PPI.
7, the obstacle data detected by the obstacle detection unit ODU is read.

In step 5107, among the data read in step 5106, the data corresponding to rlJ of register N, that is, the obstacle data obtained by the ultrasonic detectors 20a and 20b on the front side of the vehicle, is stored in register M1, and the data corresponding to rlJ of register N is stored in register M1.
The obstacle data obtained in step 30b corresponding to [2] is stored in register M2.

In step 5108, the I10 interface PPI
The controller checks ports PCO, PC2, and PO2 to read the state of the shift lever switch SWI, and selects the next process to be executed depending on the result.

First, if the shift lever is in the forward direction, step 5109
and stores its state in a register. The process then proceeds to step 5110, where the scrolling start address is set to 5c118x.

This scrolling start address is EL
Of the image memory that stores information displayed on the display,
This is the address of a memory (scrolling memory) that temporarily stores obstacle data to be written in the memory excluding the vehicle image area, and is the movement start address when display data is moved due to an interrupt caused by a vehicle speed signal. Scmax
is the maximum address value of scrolling memory.

-31=In step 5111, the contents of the register M1 are stored in the scrolling memory Xf.

In step Sl12, the contents of register M2 are set to constant D.
Compare with P. This is because the information displayed on the EL panel is data detected in front of the vehicle, and when the vehicle is moving forward and making a curve, the distance between the vehicle and the obstacle at the rear of the vehicle displayed on the EL panel is This is a process for things that are different from the actual distance, and if the distance detected by the rear ultrasonic detector is shorter than DP, the process advances to step 5113 and [
Outputs a voice warning to the VGU saying, ``Look behind you.'' In this embodiment, the distance Dp is set to 20 cm.

Steps 8114 to 8118 are similar to the processes in steps 8109 to 5113 above, and the forward movement is changed to the backward movement, and the scrolling start address Scmax is set to 5c.
m1n, memory Xf is replaced with Xr, and registers M1 and M2 are replaced.

If the shift lever is in neutral, the process proceeds to step 8119, stores the shift lever state in register L, and proceeds to step 5120. Step 5120
Then, the contents of registers M1 and M2 are stored in scrolling memories Xf and Xr, respectively.

When the above processing is completed, the scrolling memory display broroutine of step 5121 is executed.

This subroutine will be explained in detail later.

Then, in step 5122, the content of the timer interrupt memory is checked, and if it is 0, step 512
The process returns to step 03, and if the value is not 0, the process proceeds to step 8123.

In step 5123, the scrolling area of the display memory is cleared, and the process proceeds to step 5124, where a scrolling memory display routine is executed. Then, in step 5125, "0" is stored in the timer interrupt memory. After this, the process advances to step 5103 and the process can be repeated.

Before explaining the image display routine, data for displaying an image of a car will be explained. The data for displaying the image of the car is stored in the R of the system control unit SCU.
Stored in OM. Some of the data is shown in Table 2 below.

Table 2 35- Note that in Table 2, addresses and data are shown in hexadecimal with an H added. This will be explained with reference to Table 2. The start address of these data is 600
H stores the total number of data, that is, the number of points indicating the coordinates of a point or line to be displayed. In this embodiment, the total number of data is 5711, that is, 87 points. The display coordinates on the EL display are as follows: The number of pixels in the X coordinate is 3.
The number of pixels at the 20°X coordinate is 240, and the coordinate value can be expressed as one 8-bit data, but the
Since the coordinates cannot be determined, two pieces of 8-bit data are assigned to the X coordinate. In other words, one point data is
It is represented by three bytes: 8-bit data indicating the upper digit of the X coordinate, 8-bit data indicating the lower digit of the X-coordinate, and 8-bit data indicating the X-coordinate. Although the middle part is omitted in Table 2, addresses 6018 to 7051 (lower digits of the X coordinate from the 1st point to the 87th point,
The data of the upper digits of the coordinates and the X coordinate are stored.

36- Figure 10a shows a blue routine for displaying images. This will be explained with reference to FIG. 110a. First, in step 5201, the total number of point data, ie, the contents of address 600H, is stored in register Nmax.

In step 202, the data at the first point, ie, the data at addresses 60111, 602H and 603H, is read and loaded into registers X and Y. Step 5203 is a subroutine that lights up one pixel specified by registers X and Y. This will be explained in detail later.

In step 5204, register Nmax is set in register N.
Loads the value of minus 1. Step 5205
Now, set the values of registers X and Y to X in the old point coordinate memory.
Load the coordinates and the X coordinates respectively. Next, the process advances to step 5206 to read the 3-byte coordinate data of the next point and load them into the X coordinate and X coordinate of the new point coordinate memory, respectively. Step 52
07 is a subroutine for drawing a line from the coordinates of the new point coordinate memory to the coordinates of the old point coordinate memory, and this will be explained in detail later. In step 8208, the contents stored in the new point coordinate memory are loaded into the old point coordinate memory. And step 52
09, the contents of register N are decremented, and step 5
At 210, the contents of register N are checked and the contents of N are 0.
The process from step 8206 can be repeated until .

As a result, all contents from addresses 600H to 705H are read out, lines or points are displayed at predetermined pixels at positions corresponding to these point coordinate data, and the shape of the car is displayed.

FIG. 10b shows a subroutine for displaying one point, which is used in the image display routine of FIG. 10a. Before explaining this, the pixel coordinates on the EL display,
The correspondence with image memory will be explained. FIG. 11 shows the correspondence. This will be explained with reference to FIG. First, to explain the positional relationship between image memory addresses and display pixels,
■The 8-bit memory data of the address corresponds to the turning on/off of each of eight consecutive pixels in the horizontal direction.
Data bits DO to D7 are arranged from left to right. There are 320 pixels in the horizontal direction of the display screen, and one 8-bit data is data for 8 pixels, so image data for 40 addresses corresponds to one pixel line in the horizontal direction. Since there are 240 line pixels in the vertical direction of the display screen,
The pixels of the entire display screen are 9600 (40X
240) corresponds to data for an address, that is, 9600 bytes of data. In FIG. 11, the upper left of the display surface is shown as address 0, so in this case, the memory from address O to address 9599 becomes the image memory. However, in this example, there are actually 4000
H~657 9600 bytes of FH are allocated to image memory.

Regarding the pixel coordinates of the display screen, in this embodiment, the lower left of the display screen is set to coordinates 1.1 (X, Y), the X coordinate is defined as a coordinate of 1 to 320 from the left side to the right side, and the Y The coordinates are defined as coordinates from 1 to 240 from bottom to top.

Next, referring to FIG. 10b, each step 39-- of the subroutine is Explain the steps.

5300 - The specified loci IIX and Y are checked, and if X=0 or Y=0 outside the display screen is specified, the subroutine is directly terminated; otherwise, the process proceeds to step 5301.

5301-Specified seat 4! ! 1 each for X and Y
Decrement times. That is, the ranges of coordinates X and Y are now set to 0-319 and 0-239. This is a process for establishing correspondence between computer data and coordinates.

5302-X coordinate data is moved to 16-bit register S, and the contents of register S are shifted 3 bits toward the lower bits, that is, 2 bytes of data D15, DI4 . D.I.
3...D2. DI, DO D2. DI and DO
Clear the lower bits DI2 of 015 to D3.
~Move to DO.

Upper 3 bits D15. 0 is stored in DI4 and 013. This means that the coordinate X has been divided by 8. Since one memory address corresponds to eight pixels, this processing is performed to obtain a value obtained by multiplying the X coordinate by 178, which is necessary to calculate the display address by 40.

5303-Stores the starting address of the image memory plus the contents of register S into register AD.

5304-Contents of lower digits (8 bits) of X coordinate and 071
The AND with 1 is stored in register C. Now, the specified coordinates are stored in register C as D7 to DO in the image memory.
Contains data indicating the number of bits.

8305-YJIII! The value of the designated Y coordinate is subtracted from the maximum value of 240, and the value is stored in register D. This is because the image memory address value increases from the top to the bottom of the display surface, whereas the Y coordinate setting in the example is set to increase from the bottom to the top of the display surface. This is the process that has become necessary, and the memory address and Ymlj! This is the process for which response to take.

5306 - Store 40 in register T.

5307 - Store the value of AD plus the contents of register T, ie 40, in register AD.

8308 - Decrement the contents of register D by one.

5309 - Check the contents of register D, and if it is other than 0, proceed to step 5307; if it is 0, proceed to step 5310. In the processing from steps 5307 to 5309, the relative address corresponding to the specified Y coordinate value is added to register AD, and in this processing, register A
D contains the value of the specified address.

5310 - Store 1 in register B.

5311 - Shift the value of register B by the value of register C towards the upper bits. In other words, the contents of register B shift from the initial state where bit 0 is rlJ and other bits are "0", [lJ bits are shifted toward DO to D7. The resulting contents of register B become the bits of the image memory that correspond to the specified coordinates.

5321--Read the contents of the address indicated by register AD in the image memory, logically OR the value with the contents of register B, and store the result in the address indicated by register AD in the image memory. A point will now be displayed at the specified coordinates. Note that turning on a pixel corresponds to an image memory data bit of "1", and turning off a pixel corresponds to a data bit of "0".

FIG. 10c shows a subroutine for delineating the subroutine of FIG. 10a. Each step will be explained with reference to FIG. 10c.

S40〇 - Store the old point data locations @x and y in registers XO and YO, respectively, and store the new point data locations @
Store X and Y in registers Xi and Yl, respectively.

5401 - Compare the contents of registers XO and Xl and YO and Yl, respectively, and if they are equal, this subroutine is directly terminated; otherwise, the process proceeds to step 5402.

5402-Compare the contents of register XO with the contents of register X1. If they are equal, the process proceeds to step 5411; otherwise, the process proceeds to step 5403.

43-8411-register Y] and the contents of YO, and if Yl is thicker than YO, the process proceeds to step 5412; otherwise, the process proceeds to step 5413.

5412 - Load register Y with the contents of YO and load register 'YP with the contents of Yl. Register Y is used to store the Y coordinate at which a line is to be drawn, and register YP is used to store the Y coordinate at which the line ends.

5413 - Load register Y with the contents of Yl and load register Yp with the contents of Yl.

5414 - Increment the contents of register Y once.

5415-Execute the subroutine of the first Ob diagram above. Specify the coordinates of the point using registers XO and Y.

5416 - Compare the contents of register Y with the contents of yp.

Processes 5414, 5415 and 8416 are repeated until the results are equal.

5403-Compare the contents of register YO with the contents of register Y1. If they are equal, the process proceeds to step 5404; otherwise, the process proceeds to 5410.

5404 - Compare the contents of register xO with the contents of Xl,
If Xl is greater than XO, proceed to step 5409;
Otherwise, the process advances to step 5405.

5405 - Load register X with the contents of Xl.

Loads the contents of XO into register XP. Register X is for storing the X coordinate of the starting point of drawing a line, and register XP is for storing data indicating the end coordinate of the line.

5409 - Load register X with the contents of XO, and load register Xp with the contents of XI.

5406 - Increment the contents of register X once.

5407-Execute the subroutine shown in Figure 10b above. Specify the coordinates of the point using registers X and yo.

8408 - Compare the contents of register X with the contents of Xp.

Return to step 8406 until the results are equal;
Processes 8406, 5407 and S408 are repeated.

5410 - Proceed to this step if the coordinates of the old point and new point are different in both X and Y. When this step is entered, the coordinates are specified in registers X1 and Yl, the subroutine of FIG. 10b is executed only once to display one point, and the subroutine for displaying this line is skipped. In other words, in that case, the subroutine that displays this line displays only one point.

FIG. 12a shows a subroutine for displaying obstacle data stored in scrolling memory.

Each processing step will be explained with reference to FIG. 12a.

S501 - Load the scrolling start address 5cIIlin (or Scmax) into the register IX, and load the scrolling end address Scmax (or 5cm1n) into the register IY.

5502-Load register

5503 - Constant Y in register Y, contents of register IX
Load off. Here, the constant Y off is the Y coordinate where E is the largest.

5504 - Compare the contents of register Y with the maximum value of the Y coordinate, ie 240. If this content is larger than 240, the coordinates are outside the display range, so step 551
Go to 1. Otherwise, the process advances to step 5505.

5505 - Register Ye has a constant N in the contents of register Y.
Load the value plus D. Here, the constant ND is the number of pixels (the number of dots) constituting one of the vertical lines OB corresponding to the obstacle shown in FIG.

8506 - Compare the value of register Ya with the maximum Y coordinate value 240 to check whether the coordinate is within the display range. If this value exceeds 240, step 8507
, and then set the maximum value of the Y coordinate, 240, in the register Ye.
Load.

8508--Execute the point display subroutine of Figure 10b. The coordinates of the point are the contents of registers X and Y.

5509-Increment the contents of register Y 47- Ru.

8510 - Compare the contents of register Y with the contents of register Ye. The process from step 8508 is repeated until Y>Ya. When this process is completed, one vertical line is displayed on the EL display.

5511 - Load register X with the contents of register X plus constant a. Here, the constant a corresponds to the coordinate interval of each vertical line OB displayed on the EL display.

5512-Compare the contents of register

Figure 12b shows timer interrupt processing. This timer interrupt is generated at a predetermined cycle by the count of the microprocessor 200. Each step will be explained with reference to FIG. 12b.

8601 - Increment the contents of register Ts once.

5602-Compare the contents of register Ts with constant TP.

Here, the constant TP is the lap 48- This is the value that sets the period.

5603 - Compare vehicle speed data counted at the time of interruption by a vehicle speed pulse described later with a constant VP. Here, the constant VP is set vehicle speed data for determining whether or not to issue a warning.

5604-Vehicle speed is too fast, so voice generating unit vG
Give a command to U and have it output "too fast" audibly.

5605-Load 0 into register Ts and write to register storing vehicle speed data.

5606 - Store 1 to timer interrupt memory. The interrupt processing then returns to the main routine.6 Figure 12c shows the operation of external interrupt processing.

This external interrupt occurs every time the vehicle speed detection unit VDU generates a pulse. Each processing step will be explained with reference to FIG. 12c.

5701 - Increment the contents of the vehicle speed runt register once.

5702 - Check the contents of register L that stores the state of the shift lever. If the value indicates forward movement, the process proceeds to step 5704; if the value indicates reverse movement, the process proceeds to step 8703; and if the value indicates neutral, the interrupt processing is immediately terminated.

5703-Transfer the contents of the scrolling memory to sequentially higher addresses from the scrolling start address.

5704-Transfer the contents of the scrolling memory to sequentially lower addresses from the scrolling start address.

In the above embodiment, an electroluminescent display is used as the display, but a cathode ray tube display (CRT) may be used instead. In that case, the display control device may be, for example, H68CT manufactured by Hitachi.
V1 may be used.

Even in the case of a configuration using this, the pixel configuration is 320
As X240, the same operation as in the above embodiment can be performed.

Further, as the display device, in addition to the above, for example, a light emitting diode display, a liquid crystal display, a plasma display 2, etc. can be used. Regarding the display mode, in addition to line display, dot display is also used.

Bar graph display etc. can be performed.

In the above embodiment, the shape of the vehicle is displayed on the display, but it may be replaced with a sticker or the like recording the shape of the vehicle. However, if you do this, the distance between the obstacle display and the vehicle display will change depending on the viewing angle, depending on the thickness of the display glass, etc.

Accuracy decreases. Furthermore, in the embodiment, the vehicle display is fixed and the obstacles are moved, but this relationship may be reversed.

However, in that case, since the amount of information displayed on the vehicle is large, a control device (microcomputer) capable of high-speed processing is required.

In the above example, the steering wheel is on the right side of the vehicle, so two sets of ultrasonic detection means are installed on the left side. However, in the case of a vehicle with the steering wheel on the left side, a distance detector is installed. It will be placed on the right side. Furthermore, if there are many detectors, they may be provided on both the left and right sides.

51- As described above, according to the present invention, the positional relationship between the vehicle and obstacles is accurately displayed, which helps driving the vehicle and helps prevent traffic accidents that may occur due to blind spots.

[Brief explanation of the drawing]

Figure 1a is a perspective view showing the exterior of a car equipped with the device of the present invention, Figure 1b is a perspective view showing a part of the driver's seat of the car in Figure 1a, and Figure 2 is a perspective view of the vehicle installed in Figure 1a. FIG. 3a is a block diagram showing the configuration of the obstacle detection unit of FIG. 2, and FIG. 3b is a block diagram showing the configuration of the drive circuit 50 shown in FIG. 3a. , FIG. 3c is a block diagram showing the configuration of the discrimination circuit 60 shown in FIG. 3a, FIG. 4 is a block diagram showing the configuration of the system control unit SCU shown in FIG. 2, and FIG. 5 is a block diagram showing the configuration of the system control unit SCU shown in FIG. 2. Unit DCU and EL display unit E
FIG. 6 is a block diagram showing the configuration of the DU. FIG. 6 is a block diagram showing the configuration of the voice generating unit VGU shown in FIG. 2. Figures 7a and 7b are flowcharts showing the operation 52 of the obstacle detection unit ODU, respectively. FIG. 8 is a front view showing the display of the EL display panel EL. Figure 9. 3 is a flowchart showing the operation of the knit SCU. FIG. 11 is a front view showing the correspondence between display pixel coordinates on the EL display panel EL and addresses and data bits of the image memory. 1: Front bumper 2: Rear bumper 20a, 30a: Ultrasonic transmitter (position detection means) 20b
, 30b: Ultrasonic receiver (position detection means) EL: Electroluminescent display (two-dimensional display means ODU: Obstacle detection unit (distance measurement means)) SCU system control unit (control means) OB: Display obstacles
CA: Display vehicle patent applicant Aisin Seiki Co., Ltd. and 1 other person J9 ■ Taku 10a Tsukasa JP 58-221111 (20) 10th b feather start 300 YES X=○ y=() Or N. X=X-I 5301 ”” 5302 -Y ffI”r Shoulder In n7+r++ Dq 1st
2a and start 5 1X=Suf0-Re>7"Start address (Sc
min) IZ=Suf0-ri>Ge thread exhaustion 3 address (Scm
ax) 5502 x=27tl-”7-starting coordinates 55
03 Y = l

Claims (15)

[Claims] (1) At least two sets of position detection means arranged at different positions on the vehicle; distance measurement means for measuring the distance between the vehicle and the obstacle according to information from the position detection means; two-dimensional display means that displays information according to the distance between the vehicle and the obstacle; and controls to update and display information on the distance between the vehicle and the obstacle displayed on the two-dimensional display means to different coordinates at a predetermined timing according to the vehicle speed. An on-vehicle position display device comprising: control means; (2) The on-vehicle position display device according to claim 1, wherein the position detection means is an ultrasonic transmitter and an ultrasonic receiver. (3) The on-vehicle position display device 6 according to claim (1), wherein the position detecting means is disposed at the front and rear parts of the side surface of the vehicle. (4) The on-vehicle position display device according to claim (3), wherein the position detecting means is disposed on a front bumper and a rear bumper of the vehicle. (5) The on-vehicle position display device according to claim (4), wherein the position detecting means is disposed only on the side surface of the vehicle on the passenger seat side. (6) The on-vehicle position display device according to claim (1), wherein the distance measuring means includes a sensitivity changing means for setting the obstacle detection sensitivity to one of a plurality of types. (7) The distance measuring means sets the sensitivity according to the distance between the detected obstacle and the vehicle. Claim No. (6)
On-vehicle position display device as described in section. (8) The on-vehicle position display device according to claim (1), wherein the two-dimensional display means includes an electroluminescent display. (9) The on-vehicle position display device according to claim (1), wherein the two-dimensional display means includes a cathode ray tube display. (10) The on-vehicle position display device according to claim 1, wherein the control means controls the display information to be moved in one predetermined direction on the display surface coordinates of the two-dimensional display means. (11) The on-vehicle position display device according to claim (10), wherein the control means changes the direction in which the display information is moved on the display coordinates of the two-dimensional display means depending on the traveling direction of the vehicle. (12) The control means detects the traveling direction of the vehicle by setting the shift lever of the vehicle.
The on-vehicle position display device described in item 1). (13) The on-vehicle position display device according to claim 1, wherein the control means includes an alarm means for issuing an alarm. (14) The on-vehicle position display device according to claim 13, wherein the control means issues an alarm when the distance between the vehicle and the obstacle measured by the distance measuring means is less than a predetermined value. (15) The on-vehicle position display device according to claim 14, wherein the warning means includes a sound generation circuit.