JPS5938675A - Apparatus for detecting obstacle for vehicle - Google Patents

Abstract

PURPOSE:To prevent the erroneous detection of a distance, by compensating the receiving signal of a receiver for receiving reflected waves from an obstacle on the basis of the receiving signal of a noise detecting receiver provided so as to be directed to a direction not directly receiving incident reflected waves to remove a noise component. CONSTITUTION:An ultrasonic wave noise detecting receiver R3 is arranged to a position not receiving reflected waves from a warning region, for example, to the side surface of a bumper 50. When a vehicle is present in rain, the receiving signal of a receiver R1 is a synthesized wave of reflected waves of an ultrasonic pulse from a transmitter T1 at an obstacle and the ultrasonic wave component of rain sound and the receiving signal of the receiver R3 comprises only ultrasonic noise due to rain sound. A wave form wherein a noise component is removed from the receiving signal of the receiver R1 is formed in a subtraction circuit 42a. A distance detecting circuit 35a operates the distance from the vehicle to the obstacle to display the same by a distance display member 40. The reduction of S/N of the receiving signal is eliminated and the obstacle can be accurately detected.

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, C'li! can be detected by ultrasonic waves, electromagnetic waves or light to obstacles existing in a warning area around a vehicle. Obstacle detection for vehicles that detects and displays 'tlG - Relates to stone surfaces.

Conventionally, this type of obstacle detection for vehicles has the following appearance: Closed.

Taking the ultrasonic method as an example, 1511 is shown in Figure 1.
[There is something like that.

In Fig. 1, 30 is a reference signal oscillator that oscillates a reference clock pulse, and the clock pulse from the base signal generator 1 station 30 is divided into 1 minute by a frequency dividing circuit 31'' and 71''. The transmitter T provided at the rear of the vehicle is activated by the oscillation pulse of the oscillation circuit 32a synchronized with the pulse signal from the circuit 31.
Sound interruption warning: Send sonic pulses at regular intervals to the j1α region VC. and.

The ultrasonic pulse emitted from the transmitter T is reflected by an obstacle present in the warning area behind the vehicle, and the reflected ultrasonic pulse is sent to the receiver R towards the warning area.
The received signal of one reflected pulse received at 1 is subjected to waveform shaping by a tuned detection waveform shaping circuit FNI34a.

On the other hand, the detection of one ton away from an obstacle based on the propagation time of the ultrasonic wave is set by the pulse signal from the frequency dividing circuit 31.
Tuned detection waveforming circuit 34 based on the supermagnetic wave reception signal at 1
Until it is reset by the output signal from 'a', the distance 4φ output circuit (counter) 35a is the base candy 1g oscillator 30.
With the clock pulse f M+7: 1-, the propagation time of the superordinate wave signal ijl iυj added to the pulse signal from the frequency divider circuit 31 is determined to be 1llJ, and this measurement 15〒,
Calculate the distance from the vehicle to the obstacle based on the air propagation speed IW of the ultrasonic wave.
J￥, I'm trying to secretly show the huge distance up to the snout.

Incidentally, in this conventional example 11~, in addition to the signal shaker 30 configured as described above, 〃; Frequency divider circuit 3]
and distance display section, H @ , to share, launch 4 shield times I
热32b Transmission''F-T2, receiver R7, flip-flop 33b.

Tuned detection wave shaping circuit 34 +) *Distance detection circuit 351)
Another rectangular obstacle detection device is installed, and these two sets of devices expand the obstacle warning area by 1 -C.

By the way, in the vehicle obstacle 4/ρ button device as described above,
Measure the distance to the obstacle using ultrasonic waves and calculate the distance 1ij
Since the lI is displayed, even if there are obstacles in the driver's rear blind spot, reliable driving operations can be performed.

However, such conventional obstacle 1 arrow detection devices use ultrasonic waves to measure back the distance to the obstacle, so in rainy weather, for example, the sound of rain when both sides hit the vehicle body or the ground, etc. , ultra-high frequency components included in exhaust noise etc. enter the receiver as noise, and if there is an obstacle far away or if the reflectance of the harmful object is low, there is a problem.
Because the received signal level due to the reflected wave from the proboscis is small, S
There was a risk that the /N ratio would drop and the noise component would cause a malfunction in which the wrong distance [f] was detected.

In addition, even with devices that use light instead of ultrasonic waves to measure the distance to 1) and 3 harmful objects, the S/N ratio of the received signal of reflected light may be similar due to sunlight, street lights, etc. Furthermore, even when installed internally using radio waves, the S/N ratio of the received signal of reflected waves decreases due to noise from the vehicle's ignition system, amateur radio, etc. Similarly, there was a risk of making mistakes.

The present invention has been made in view of the above, and includes a transmitter that is installed toward a warning area around a vehicle and emits ultrasonic waves, electromagnetic waves, or light at a rate of 1σ in one orbit, and obstacles that exist in the warning area. A receiver that receives the reflected wave from the proboscis, and a propagation time from when the ultrasonic wave, electromagnetic wave, or light is emitted by the 1N'C' radio signal until the reflected wave from the proboscis is received by the receiver. In the vehicle obstacle detection system @tL, which consists of calculation display means that calculates and displays the distance to the obstacle based on In order to prevent the signal S/N ratio from decreasing and erroneously detecting the distance, place the 4-tone sound detection receiver near the receiver (in a direction where the reflected waves are not directly incident). established,
Based on the received signal of the miscellaneous FF detection receiver, the received A8 signal of the receiver is corrected to remove the miscellaneous M-component.

The tree will be explained below with reference to the drawings.

PIZ 2 is a block diagram showing one embodiment of the present invention.

First, a super-crossover wave is fired at regular intervals toward a detection area behind the vehicle to detect obstacles. Wakanobuko T,,T,
and the above-mentioned warning area force), which receives the reflected waves from the
, R2 are arranged in front of the rear bumper 50 as shown in Figure 3, and furthermore, the receiver R3 for ultrasonic noise detection is located at a position where it does not receive reflected waves from the stomach area. For example, it is installed at 1111 of Bamba 50.

Next, the configuration of the entire device will be explained. 30 is a reference signal generator that generates a clock pulse.

31 is a frequency dividing circuit that divides the frequency of the clock pulse from the reference signal oscillation type 30; 32a is a tortoise-four circuit that generates four pulse signals in synchronization with the pulse signal from the dividing circuit 31;
Conventional device 4 parts, f; excavation pulse 1 from eye circuit 32a
No. 3 excites the transmitter T installed at the rear of the vehicle to transmit ultrasonic waves toward the rear warning area. 41a
F′i A tuned detection circuit that tunes and detects the received signal due to the reflected wave from an obstacle received by the receiver R, 41C The receiver R3 for ultrasonic noise detection receives 1. Tuned detection circuit that tunes and detects super backwave noise.

44 is the output signal from the tuned detection circuit 4]c multiplied by a coefficient p
etc. (¥, government equipment, 42a is the tuned detection circuit 4
] A subtraction circuit that subtracts the output signal of the coefficient multiplier 44 from the output signal from a, 43a is a subtraction circuit, the output of the circuit 42a is -,
The signal is processed by a waveform shaping circuit. Then, in the conventional equipment 1 and 1, a flip-flora 7' 33a set by the pulse signal from the frequency dividing circuit 31 is used to detect the reflected wave from the ISI harmful object received by the receiver 1 (, The distance detection circuit (counter) 35a counts the clock pulses from the quasi-signal foil sensor 30 until it is reset by the output signal of the shaping circuit 43a based on the received signal. ), the sender ′I゛1
It was fired from. ii'4 Measure the propagation time of the sound wave pulse [
5. Based on this shaving W time and the propagation of the sound wave (3), calculate the distance from the vehicle at i, 'l':'?harm' proboscis dimension based on the general speed, and display the distance '1iff' on the display part 40. Chapter 1 Haramaka 17p fha+
? 15 pa+# is now being used frequently.

f lr, Honjitsu/A I'll also have 11i configured as above! i rha (114, sawa i, 141 words uttered 11% 'd% 30, min L'jJ times Wr
31.

Coefficient unit 44. 71 oscillation path 32b, transmitter T2, receiver R2, flip-flop 33b, distance detection circuit 35b, tuned detection circuit 41
Another set of obstacle detecting devices consisting of a subtracting circuit 42b, and a shaping circuit 43b is provided, and these two sets of devices expand the detection range of obstacles.

Note that the installation location of the receiver R for detecting sonic noise M is not limited to the bumper 500 as shown in Figure 3), but is also used to directly receive reflected waves from obstacles in the warning area. In such a position, if it is near the receivers R, R7, turn the receiving surface toward the receiver and the upper part of the bumper 50 or the receiving surface downward, as shown in FIGS. 41 and 5, respectively. It may also be installed at the bottom of the bumper 50 or the like.

Next, the operation will be explained with reference to the 'f signal waveform diagram shown in FIG.

When a vehicle drifts in the rain, the received signal at receiver 1 consists of the ultrasonic pulse from transmitter T1 reflected by an obstacle and the ultrasonic component of the rain sound when the mountain hits the vehicle body or the ground. The signal received by the receiver R8 is deviated as shown in waveform B with only @ff wave noise due to the rain sound as described above.

Here, the ultrasonic signal received by the receiver R is subjected to a tuned detection circuit 413''r' so that the waveform C is obtained.
The ultrasonic noise received by the receiver R8 is transmitted to the tuned detection circuit 41c.
After the tuning 1 wave is broken, the coefficient is intercepted by the coefficient multiplier 44, resulting in a waveform like that. and.

The output signal of the coefficient 544, which becomes one skin shape from the output signal of the tuned detection circuit 41a, becomes waveform C in the subtraction circuit 42a. The ultrasonic noise component is removed from the locus wave signal, which becomes a waveform, and the output signal of the circuit 42a is shaped by the waveform shaping circuit 43aK.

Next, as in the conventional epitaph, the flip roller 7' 33 is set by a pulse signal from the frequency dividing circuit 31.
a; O', until the output signal of the shaping circuit 43a is reset: the weight detection circuit 35a), (clock pulse 7 from the 4-pin generator 30, -B+I9,
From this count value, the time lI'lr required for the ultrasonic wave emitted by the transmitter T to be reflected by an obstacle and received by the receiver 11 is calculated, and furthermore, this time and the ultrasonic wave The distance (θ) from the vehicle to the obstacle based on the evening speed is calculated, and the distance display member 40 displays the distance M-j l'
+ll is displayed.

In addition, in the above-mentioned embodiment, the combination of the 61-sound wave was explained, but when using light, an optical filter may be used instead of the 4th line and f'L.

In addition, the base No. 4i oscillator 301 frequency dividing circuit 31. Receiver R
,,The wave circuit 41c, the coefficient multiplier 44, and the distance display member 40 are shared in synchronization, and the oscillation circuit 321) is composed of the core 42b and the shaping circuit 43b. Let's do a poem I.

(hereinafter) As explained above, according to the present invention e, obstacles]
Omniscient r (lr7 p that is unaffected by the ultrasound signal used)
The receiver I-3VC installed at the bottom detects the rain sound and the sound component included in the exhaust sound, and this detection signal is connected to 1 R% and the 7-bit fire is detected.しζReceiver■尤1. R
7 to detect...-&n skin 1. If you say no, do you want to gain success from your thrifty spending power and overcome obstacles? 1
1 To remove the influence of ultrasonic background noise associated with the
Therefore, the S/N ratio of the received signal of the foul wave will not decrease due to ultrasonic waves, rain, magnetic waves, or light noise.
It has the added benefit of being able to accurately detect obstacles.

[Brief explanation of the drawing]

A block diagram showing an example of a vehicle obstacle detection device of 11 VI (, Reception of background noise f l-t 3 (,') it'(k rank (・'i
An example of this is an explanatory diagram of the failure, Fig. 4 shows 14 receivers 1t, (1) Installation? ”: An explanatory diagram showing another example of L'L fpe.
The target that accepts 1, hits “Zul, 61st Sol 6:t j′Jb
The various parts of the embodiment shown in Figure 2 ('r?
1 stone in the 7th rule good waveform diagram. 30...Group 1■Signal/Road camera 3j...Frequency dividing circuit 3
2g, 3zb-□q? 1h+Ij7Q 33a, 33b
...Flip-flops 35a, 35b...Distance detection circuit 40...17 Great distance display member 41a, 7111
), 4]C-tuned detection circuit 42a, 42b・-
tjQ q l+1lR143a, 43b...°Liquid type circuit 44...Coefficient unit 'L 19 'r 2 '''
Transmitter R+ -R2, Rs -4N child Patent applicant Nissan Motor Co., Ltd. Patent attorney Hao Tsuchihashi Figure 3 50 395- 4 ii Figure 5 0 7Z Otsu 74 koku l

Claims (1)

[Claims] The ultrasonic wave is installed toward a warning area around the vehicle. A light device that emits rain, magnetic waves, or light at regular intervals. Receive reflected waves from obstacles existing in the above warning area 1-
The receiver calculates the distance to the obstacle based on the propagation time from when the transmitter emits ultrasonic waves, electromagnetic waves, or light until the reflected wave from the obstacle is received by the receiver. In the vehicle obstacle detection device comprising calculation display means which displays '1-', the above '/f: +c Hz in the vicinity of the receiver in a direction where the reflected waves from the Kai IIu region are not directly incident. and a noise removing means for correcting the received signal of the receiver to remove noise components based on the received signal of the noise detecting receiver. Obstacle detection device for vehicles.