JPS6281588A - Obstacle detection device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an obstacle detection device that uses radar to detect obstacles.

Conventionally, vehicles are equipped with ultrasonic radars that measure the distance to objects by transmitting pulsed ultrasonic signals and measuring the time it takes for the reflected waves from an object to be received. An obstacle detection device has been developed that detects whether or not there is an obstacle within a certain distance range in the running direction and issues an alarm when an obstacle is detected.
(Refer to Utility Application No. 126744/1983).

In such conventional obstacle detection devices, not only ultrasonic waves but also general radars of this kind have directional properties, so in order to detect obstacles over a relatively wide range, multiple radars must be installed in parallel. Therefore, it is necessary to have each radar perform monitoring within a correspondingly divided area.

However, when using multiple radars to detect obstacles over a relatively wide area,
Obstacle detection resolution, which determines how many obstacles are present in the radar monitoring area when an obstacle is detected, depends on the number of radars installed in parallel. It becomes impossible to obtain resolution.

And moss The present invention has been made in consideration of the above points.

To provide an obstacle detection device capable of obtaining resolution greater than the number of radars installed when a plurality of radars are installed in parallel to detect obstacles over a relatively wide area. It is.

In order to achieve the object, the present invention installs at least two radars in parallel so that the monitoring areas of each radar partially overlap, and performs logical judgment based on the combination of output states of obstacle detection by each radar. In addition, it is possible to detect in which of the three areas in which the monitoring area of the two radars is apparently divided, an obstacle is present.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the obstacle detection device according to the present invention, as shown in FIG.
A signal processing circuit 2 that reads the output signals Sa and Sb of A and IB and performs a predetermined logical judgment for detecting an obstacle, and an alarm 3 that makes a notification that an obstacle has been detected in accordance with the output signal of the signal processing circuit 2. It is made up of.

Here, each radar IA and IB detects an object by transmitting waves such as radio waves, ultrasonic waves, and light, and receives reflected waves from the object, and also measures the time from transmission to reception of the waves. A device that measures the distance to a detected object is used. In the figure, SA and SB are radio waves and ultrasound waves.

Each radar lA, I transmits and receives waves such as light.
The sensor portions of B are shown.

Moreover, each radar IA and IB have their monitoring area A.

The respective monitoring areas A and B are arranged side by side so as to partially overlap so that area B is apparently divided into three areas a, b, and c.

As shown in FIG. 2, the alarm 3 has each radar IA,
Display sections 3a, 3b, and 3e corresponding to areas a, b, and c obtained by dividing monitoring areas A and B of B into three are provided.

FIG. 3 shows a specific example of the configuration of radars IA and IB.

Here, an ultrasonic radar is used as the radar 1 (IA, IB), and the transmitter 11 provides a transmission signal to the transmitter HT.
, a pulse oscillator 12 that provides a pulse drive signal to the transmitter 11, a receiver 13 that receives the reflected wave from the object O through the receiver HR, and a reception signal after the pulse drive signal is generated from the pulse oscillator 12. The distance to object 0 is determined by measuring the time until object 0 is obtained, and when object 0 is detected within a preset distance, output signal S
(Sa, Sb) is set to high level II HII, and if object O is not detected within that distance range, output signal S
The distance measuring circuit 14 sets the low level 11L1g.

The signal processing circuit 2 controls the lighting of the display sections 3a, 3b, and 3c in the alarm 3 based on logical judgment based on a combination of output signals Sa and Sb from each radar IA and IB.

At that time, when the control signals for blinking the respective display parts 3a, 3b, and 3c of the alarm 3 are Da, Db, and DC,
The logical equation in the signal processing circuit 2 is given by the following equation.

Da=Sa-1 Db=Sa-5b Dc=S a -S b In the obstacle detection device configured in this way, the output signal Sa of the radar IA is currently at a high level "H", and the radar When the output signal sb of IB becomes low level "L", the signal processing circuit 2 sets only the control signal Da to high level"
'H'', and the other control signals Db and DC are set to low level II L II, respectively, and the display section 3a of the alarm 3
lights up.

Therefore, when the display section 3a of the alarm 3 lights up, it can be seen that the detected object 0, that is, the obstacle, is within the area a monitored by the radar IA.

The output signal Sa of the radar IA is low level.
TE, L/-ta IB output signal sb is high level “H”
``'', the signal processing circuit 2 outputs the control signal Db
Only the control signal Da is set to high level 11 HII, and the other control signals Da
, Dc are set to low level #L'g, and the display section 3b of the alarm 3 is turned on.

Therefore, by lighting up the display section 3b of the alarm 3, it can be seen that the object O, that is, the obstacle detected at that time, is within the b area monitored by the radar IB.

Further, when the output signal Sa of the radar IA and the output signal sb of the radar IB are both at a high level "tr11", the signal processing circuit 2 outputs only the control signal DC to a high level "I".
I HIN, and the other control signals Da and Db are set to low level II L'', respectively, on the display section 3 in the notification 13.
Turn on c.

Therefore, by lighting up the display section 3C of the alarm 3, it can be seen that the object ○, that is, the obstacle detected at that time, is within the C area under the overlapped monitoring of the radars IA and IB.

Further, when the output signal Sa of the radar IA and the output signal sb of the radar IB both become low level II L PI, the signal processing circuit 2 outputs all the control signals Da, Db,
Display parts 3a, 3b, with Dc set to low level "L",
3c is not lit at all.

Therefore, the alarm 3 does not light up.

It can be seen that there is no object O, that is, no obstacle, in each of the monitoring areas A and B of radars IA and jB.

Thus, according to the invention, two radar IAs.

When looking at each monitoring area A and B of IB, the top three areas a and b
,c, each radar IA.

The resolution of obstacle detection by IB can be substantially increased.

Generally, if the number of installed radars is n, the resolution of obstacle detection according to the present invention is (2n-1).

As described above, in the obstacle detection device according to the present invention, when multiple radars are installed in parallel to detect obstacles over a relatively wide area, the monitoring areas of each radar overlap partially. It has the excellent advantage that the resolution of obstacle detection can be improved by taking a simple means of making a logical judgment based on a combination of the output signals of the respective radars.

[Brief explanation of drawings]

Fig. 1 is a block configuration diagram showing an embodiment of the obstacle detection device according to the present invention, Fig. 2 is a diagram showing an example of the configuration of the display section of the alarm in the same embodiment, and Fig. 3 is applied to the same embodiment. FIG. 2 is a block diagram showing an example of a component of a radar.

Claims (1)

[Claims] At least two radar means provided so that the monitoring areas of the two radars for measuring distances to obstacles are apparently divided into three areas so that the monitoring areas of each radar partially overlap, and obstacles caused by each radar. An obstacle detection device that detects in which area an obstacle exists by performing logical judgment based on a combination of output states of object detection.