JP3020584B2 - Obstacle detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an obstacle detection device mounted and used on a moving body such as an automobile.

(Related Art) Recently, progress in safety measures for automobiles has been remarkable, and for example, there is an automobile equipped with an obstacle detection device capable of detecting an obstacle left on a traveling path of the automobile in advance. .

Conventionally, this type of obstacle detection device mounted on an automobile mounts an antenna 2 on the front of a vehicle body 1a of the automobile 1 as shown in FIG. There has been proposed an apparatus that detects the presence or absence of an obstacle by receiving a reflected wave reflected from an object and utilizing the Doppler effect.

(Problems to be Solved by the Invention) However, in such a configuration, the radar radio wave 3 emitted from the antenna 2 provided on the front of the vehicle body 1a of the automobile 1 is directed to the front of the vehicle body 1. , Sixth
When traveling on a curve as shown in the figure, the wheels 1b, 1b in front of the vehicle body 1 move along the curve due to the driver's steering operation, but there is a time delay before the entire body 1a changes direction. Cause the card rail 4
When the vehicle is laid, the reflected wave from the guardrail 4 is detected, and there is actually no obstacle on the traveling path. There was a problem that erroneous detection information was output. Such an erroneous detection is more likely to occur as the curve radius of the traveling road becomes smaller.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an obstacle detection device that can always accurately detect an obstacle regardless of the radius of a curve of a traveling road.

[Configuration of the Invention] (Means for Solving the Problems) According to the present invention, at least two antennas for receiving reflected waves from obstacles are provided at a predetermined interval in front of the moving body in the traveling direction, and these antennas are used. While detecting the presence or absence of the obstacle based on the given received signal, and when the mobile object is running in a curved direction, a received signal from an antenna located on the opposite side to the bending direction of the mobile object is bent in the bent direction. Obstacle detecting means for attenuating the presence of an obstacle detected by the antenna by attenuating according to the degree, and determining a danger in running of the moving body based on a detection result of the obstacle detecting means. It is configured to judge by the following.

(Operation) As a result, according to the present invention, the presence or absence of an obstacle is determined based on the reflected waves received from at least two antennas provided at predetermined intervals in front of the moving body in the traveling direction. In addition, when the mobile body is traveling in a curved direction, even if a received signal is given from an antenna located on the side opposite to the bending direction of the mobile body, the received signal obtained by this antenna is converted into the bending direction. By attenuating according to the degree of bend to the vehicle and neglecting the presence of the detected obstacle, obstacles located on the opposite side to the bending direction of the moving object are neglected, and priority is given to obstacles in the same direction. This makes it possible to make a correct determination that there is no danger of collision even if there is an obstacle.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a circuit configuration of the embodiment.
1 shows an example in which the present invention is applied to an obstacle detection device mounted on an automobile. In the figure, reference numeral 11 denotes a transmitting unit, and the transmitting unit 11 outputs a pulsed transmission signal.

The transmission signal of the transmission unit 11 is sent to the distributor 12, where
And distributed to the circulators 131 and 132, respectively.

These circulators 131 and 132 have two antennas
141 and 142 are connected, and by these antennas 141 and 142,
The pulse transmission signal transmitted from the transmission unit 11 is output as radar radio waves 141a and 142a.

In this case, these two antennas 141 and 142 are mounted on both sides of the front of the vehicle body 31 of the automobile 30 in the traveling direction as shown in FIG. The radar radio waves 141a and 142a output from the antennas 141 and 142 are emitted with a predetermined beam width. Further, the antennas 141 and 142 receive reflected waves of the radar radio waves 141a and 142a reflected by obstacles.

The signals received by the antennas 141 and 142 are sent to circulators 131 and 132, and sent to the receiving units 151 and 152 by the circulators 131 and 132.

The receiving units 151 and 152 convert the received signal into a signal that can be easily processed, that is, an intermediate frequency signal. The outputs of the receiving units 151 and 152 are output from the variable attenuators 161, 1
62 is sent to the synthesizer 17 via each of them.

In this case, the variable attenuators 161 and 162
The weights are given to the outputs of the receiving units 151 and 152 in accordance with the instruction. Here, the weighting of the variable attenuators 161 and 162, that is, the amount of attenuation, is controlled based on the output of the steering wheel operation detecting unit 19. Is detected, control is performed in a direction in which the amount of attenuation in the variable attenuator 161 is increased in accordance with the steering wheel operation amount. Conversely, when the steering wheel operation detecting unit 19 detects a leftward steering wheel operation of the automobile 30, the steering wheel is controlled. The control is performed in a direction to increase the amount of attenuation in the variable attenuator 162 according to the amount of operation.

The combiner 17 combines the outputs from the receiving units 151 and 152 output through the variable attenuators 161 and 162.

The output of the synthesizer 17 is sent to the obstacle detection circuit 20. The detection circuit 20 detects the presence or absence of an obstacle from the output synthesized by the synthesizer 17.

The information on the presence or absence of the obstacle detected by the detection circuit 20 is sent to the signal processing control unit 21.

When the signal processing control unit 21 receives the information on the presence or absence of the obstacle from the detection circuit 20, the signal processing control unit 21 transmits the transmission signal from the transmission unit 11 and the reception unit 15
The distance from the vehicle 30 to the obstacle is calculated from the time difference from the received signal at 1, 152, and the degree of danger is determined based on the speed of the vehicle 30, the direction of the wheels 32, and the like. The result of the signal processing by the signal processing control unit 21 is output from the output terminal 22, and the vehicle 30 is caused to execute an alarm display, a brake operation, and the like according to the degree of danger.

Next, the operation of the embodiment configured as described above will be described.

Now, when a pulse-shaped transmission signal is output from the reception unit 11, the transmission signal from the transmission unit 11 is sent to the distributor 12, where it is distributed in two directions, and each of the circulators.
It is sent to 131,132. And these circulators 13
The antennas 141 and 142 send the signals to antennas 141 and 142, respectively, and output the radar waves 141a and 142a from these two antennas 141 and 142.

In this case, these two antennas 141 and 142 are mounted on both sides of the front of the vehicle body 31 of the automobile 30 so as to face the front, respectively, as shown in FIG.
Radar radio waves 141a and 142a are emitted from 141 and 142 with a beam width having a predetermined spread, respectively.

Here, for example, assuming that there is an obstacle A in front of the automobile 30 traveling on a straight traveling path as shown in FIG. 2A, the radar radio waves emitted from the antennas 141 and 142
141a and 142a respectively catch obstacle A and are reflected,
The reflected waves are received by the antennas 141 and 142. The signals received by these antennas 141 and 142 are sent to circulators 131 and 132, and the circulators 131 and 1
It is guided to the receiving units 151 and 152 by 32.

The received signals received by the receiving units 151 and 152 are converted into intermediate frequency signals that can be easily processed, and the outputs of the receiving units 151 and 152 are sent to the combiner 17 via the variable attenuators 161 and 162.

In this case, the traveling direction of the vehicle 30 is straight ahead, and the steering wheel operation detection unit 19 does not detect the steering wheel operation in the automobile 30. Therefore, the variable attenuators 161 and 162
Is not issued.

Therefore, in this case, the outputs of the receiving units 151 and 152 are sent to the combiner 17 as they are without being attenuated by the variable attenuators 161 and 162 and combined.

Then, the output synthesized by the synthesizer 17 is sent to the obstacle detection circuit 20, and the presence or absence of an obstacle is detected. Here, the obstacle A is detected from the outputs of the receiving units 151 and 152, and this detection information is sent to the signal processing control unit 21.

When the signal processing control unit 21 receives the detection information indicating the presence of an obstacle from the detection circuit 20, the transmission signal of the transmission unit 11 and the reception unit 15 are received.
Obstacle A from the car 30 based on the time difference from the received signal of 1,152
Is calculated, and the degree of danger is determined based on the speed of the automobile 30, the direction of the wheels 32, and the like.

Then, when the signal processing control unit 21 determines that the obstacle A is dangerous for the traveling of the car 30 from these calculation results,
An alarm display and a command output of a brake operation are output from the output terminal 22 to notify the driver that there is a dangerous obstacle, and at the same time, the brake of the automobile 30 is automatically activated, thereby causing a danger from the obstacle A. Is avoided.

Next, as shown in FIG. 2 (b), a case will be described in which an obstacle B is present on the left front of the automobile 30 that turns along a right-curved road. Also in this case, the radar radio waves 141a and 142a are emitted from the antennas 141 and 142, but the obstacle B is
, The radar radio wave 141a emitted from the antenna 141 is caught and reflected by the obstacle B, and is received by the antenna 141 as a reflected wave.

Then, the signals received by the antennas 141 and 142 are
The circulators 131 and 132 send the circulators 131 and 132 to the receivers 151 and 152. Then, the signals are converted into intermediate frequency signals that can be easily processed by the receiving units 151 and 152, and sent to the combiner 17 via the variable attenuators 161 and 162, respectively.

In this case, since the vehicle 30 is turning rightward and the steering wheel operation detecting unit 19 detects the rightward steering wheel operation along the right curve traveling path, the attenuator control circuit 18
A control instruction to increase the amount of attenuation of variable attenuator 161 is output.

Therefore, in this case, the output from the receiving unit 151 is
It is greatly attenuated by the variable attenuator 161 and the receiving unit 1
Only the output from 52 is sent to the combiner 17 through the variable attenuator 162 as it is.

The combined output of the combiner 17 is output to an obstacle detection circuit.
It is sent to 20 and the presence or absence of an obstacle is detected. Here, since the output from the receiving unit 151 is greatly attenuated, the detection circuit 2
0 means that the obstacle B is ignored and the risk is not detected as being high.

That is, as shown in FIG. 2 (b), when the vehicle 30 is turning along a right-curved road, the wheel 32 in front of the vehicle body 31 is turned rightward by the driver's steering operation. Although the vehicle runs along a curve, a time delay occurs when the direction of the vehicle body 31 changes. Therefore, if there is an obstacle B on the left front of the vehicle 30, the obstacle B is emitted from the antenna 141. May be caught by the generated radar radio wave 141a. However, in such a case, the output of the receiving unit 151 to which the reflected wave from the obstacle B is given is output from the variable attenuator 161.
Therefore, the obstacle B in the left direction of the vehicle 30 is neglected, and only the obstacle in the right direction is emphasized. As a result, it can be correctly determined that there is no danger of collision even if the obstacle B is in front of the left side of the vehicle 30.

Note that, in the above description, the case where the obstacle B is located on the left front of the car 30 that turns along the right curve traveling path is described. However, the obstacle B is located on the right front of the car 30 that turns along the left curve traveling path. The same applies when there is an obstacle. in this case,
Since the output of the receiving unit 152 to which the reflected wave from the obstacle on the right front of the car 30 is given is greatly attenuated by the variable attenuator 162, the obstacle in the right direction of the car 30 is neglected,
Only the obstacle in the left direction is regarded as important, so that it is possible to make a correct determination that there is no danger of collision even if the obstacle is right ahead of the vehicle 30.

Next, FIG. 3 shows another embodiment of the present invention.

In this case, the signals received by the antennas 141 and 142 are sent to circulators 131 and 132, and these circulators
Combiner via variable attenuators 161 and 162 separately from 131 and 132
It is sent to 17. The output combined by the combiner 17 is sent to the receiving unit 22. That is, in this case, the receiving unit 22 is configured to be common.

Other configurations are the same as those in FIG. 1, and the same portions are denoted by the same reference numerals and description thereof will be omitted.

By doing so, there is a loss in the received signal at the receiving unit 22, and it is conceivable that the detection accuracy may be slightly reduced. However, by using the common receiving unit 22, the configuration can be simplified and the price is low. Things are obtained. Of course, also in this case, the same effects as described above can be expected.

Next, FIG. 4 shows another embodiment of the present invention.

In this case, the transmission signal of the transmission unit 11 is
Are transmitted to the antennas 141 and 142 via the circulators 131 and 132 alternately by the operation of the first switch 23, and are output as radar radio waves 141a and 142a. Also,
The signals received by the antennas 141 and 142 are
131, 132 to the second switch 24,
By the operation of the switch 24, the data is alternately sent to the receiving unit 25. Then, the receiving unit 25 converts the received signal into an intermediate frequency signal which is easy to process and sends it to the detection circuit 20.

In this case, the first and second switches 23 and 24 operate in synchronization with each other, and when the transmission signal of the transmission unit 11 is supplied to the antenna 141, the signal received by the antenna 141 is When the transmission signal of the transmission unit 11 is supplied to the reception unit 25 and, conversely, the transmission signal of the transmission unit 11 is supplied to the antenna 142, the signal received by the antenna 142 is input to the reception unit 25.

Other configurations are the same as those in FIG. 1, and the same portions are denoted by the same reference numerals and description thereof will be omitted.

By doing so, the first and second switches 23, 24
, The reflected signals received by the antennas 141 and 142 can be detected in a time-division manner, so that the levels of the received signals provided by the antennas 141 and 142 are equal and the distance to the obstacle calculated from each received signal is equal In order to detect that an obstacle is located in front, and to detect only one of the received signals, it is possible to detect that there is an obstacle on the antenna side that outputs the received signal when viewed from the car. From this result, obstacles located on the opposite side of the curve direction of the car can be neglected, and a judgment can be made such that obstacles in the same direction are valued. You can make a correct judgment, such as not having.

The present invention is not limited to the above-described embodiment, but can be appropriately modified and implemented without departing from the scope of the invention. For example,
In the above-described embodiment, the case where there are two antennas has been described, but two or more antennas may be provided. Also,
In the above-described embodiment, the obstacle detection device mounted on an automobile has been described. However, the invention can be applied not only to vehicles other than automobiles but also to ships and the like.

[Effects of the Invention] The obstacle detection device of the present invention is provided with at least two antennas for receiving reflected waves from an obstacle at a predetermined interval in front of the moving body in the traveling direction, and receiving signals provided by these antennas. While detecting the presence or absence of the obstacle on the basis of the above, at the time of the curved running of the moving body, the received signal from the antenna located on the opposite side to the bending direction of the moving body according to the degree of bending in the bending direction Obstacle detecting means for attenuating and lightening the presence of an obstacle detected by the antenna is provided, and the danger of traveling of the moving body is determined by the determining means based on the detection result of the obstacle detecting means. Therefore, the presence or absence of an obstacle is determined based on reflected waves from obstacles received from at least two antennas provided at predetermined intervals in front of the moving body in the traveling direction. In addition, when the mobile body is turning and traveling, when a reception signal is given from an antenna positioned on the opposite side to the bending direction of the mobile body, the presence of an obstacle detected by the antenna is determined as described above. By neglecting according to the degree of bend in the bend direction, obstacles located on the opposite side to the bend direction of the moving object can be neglected, and it can be determined that obstacles in the same direction are important. Even if there is an obstacle, it is possible to always correctly detect obstacles regardless of the radius of the bend of the running path, such as making a correct judgment that there is no danger of collision depending on the traveling direction. become. In addition, the obstacle detection device of the present invention is provided with at least two antennas at a predetermined interval in front of the traveling direction of the moving body and with the receiving direction fixed, so that the receiving direction can be changed. As compared with the case of detecting an obstacle, the configuration and control are simpler and can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration of one embodiment of the present invention, FIG. 2 is a diagram for explaining the operation of the embodiment, and FIG. 3 is a circuit of another embodiment of the present invention. FIG. 4 is a block diagram showing a circuit configuration of another embodiment of the present invention, and FIGS. 5 and 6 are diagrams for explaining the operation of a conventional obstacle detection device. It is. 11 ... Transmission unit, 141, 142 ... Antenna, 151, 152, 22,
25 receiving unit, 161, 162 variable attenuator, 17 synthesizer, 18 attenuator control circuit, 19 steering wheel operation detection unit, 20 obstacle detection circuit, 21 signal processing Control part, 2
3, 24 ... switch, 30 ... car, 31 ... body, 32 ...
…Wheel.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01S 13/93 G01S 7/02

Claims (2)

(57) [Claims] 1. A moving body, at least two antennas provided at a predetermined interval in front of the moving body in a traveling direction and receiving reflected waves from an obstacle, and based on a reception signal given from these antennas. In addition to detecting the presence or absence of the obstacle, a signal received from an antenna located on a side opposite to the bending direction of the moving body is attenuated according to a degree of bending in the bending direction when the mobile body is traveling in a curved direction. Obstacle detecting means for neglecting the presence of an obstacle detected by the antenna; and determining means for determining a danger in traveling of the moving body based on a detection result of the obstacle detecting means. An obstacle detection device characterized by the following. 2. The obstacle detection device according to claim 1, wherein the at least two antennas are provided at a predetermined interval in front of the moving body in a traveling direction and fixed in a receiving direction. apparatus.