KR101970010B1 - System and Method for Car Detecting by Using Plural Ultrasonic Sensors - Google Patents

Abstract

A vehicle detecting apparatus using a plurality of ultrasonic sensors and a detecting method thereof are disclosed. The vehicle detecting apparatus of the present invention can detect a vehicle using a plurality of ultrasonic sensors, measure the traveling direction of the vehicle, and the width of the vehicle. By controlling a plurality of ultrasonic sensors based on one synchronizing signal, So that the ultrasonic transmission of the sensor is synchronously output at the same time. With this synchronous control, the detection device can eliminate or ignore the noise generated by the ultrasonic wave directly received by the other ultrasonic sensor in the process of processing the received signal of the ultrasonic sensor. Naturally, detection errors can also be prevented.

Description

Technical Field [0001] The present invention relates to a vehicle detecting apparatus using a plurality of ultrasonic sensors,

The present invention relates to an apparatus for detecting a vehicle using a plurality of ultrasonic sensors, and more particularly, to a vehicle detection apparatus and method for eliminating detection errors by eliminating noise among a plurality of ultrasonic sensors by a synchronization technique will be.

Ultrasonic sensors, which are widely used as proximity sensors, can output ultrasonic waves of a certain frequency forward and receive sound waves reflected from the object. The ultrasonic sensor includes a vibration element for generating ultrasonic waves, an oscillator for oscillating the vibration element at its natural frequency (or a vibration frequency), and a signal processing unit for extracting and amplifying a signal from the received sound wave do.

A vibration plate having a natural frequency of about 40 kHz is often used as the vibration plate. When the oscillator oscillates the oscillation element at its natural frequency, the oscillation element generates ultrasonic waves corresponding to the natural frequency and outputs the generated ultrasonic waves forward. And then receives again the sound waves reflected from the forward object. Since the ultrasonic wave transmitted forward and the ultrasonic wave reflected from the object travel at almost the same speed, the time of flight (TOF) from the generation of the ultrasonic wave to the forward direction, And the distance between the objects can be calculated.

The speed of the ultrasonic wave is affected by the temperature. The traveling speed Vu of the ultrasonic wave according to the temperature is approximated as shown in the following equation (1).

Here, T is the temperature (占 폚).

Therefore, the distance P from the ultrasonic sensor head to the sensing object is calculated by the following equation (2).

Here, Tm represents a flight time (TOF) until ultrasonic waves are emitted, reflected on an object, and received again. The distance to the target object can be measured based on Equation (2) by measuring the flight time from the point of time when the ultrasonic wave is generated to the point of time when it is reflected and received again. Therefore, the ultrasonic sensor includes a transmitter for generating ultrasonic waves and emitting the ultrasonic waves, and a receiver for detecting the reflected ultrasonic waves.

The transmitting part and the receiving part of the ultrasonic sensor may be configured as separate parts physically separated from each other, or the transmitting part and the receiving part may be integrally formed for various purposes. In the case of an integrated type, it is very important to control the timing of transmission and reception, since a single diaphragm must be used to transmit and receive signals.

Fig. 1 shows an example of controlling transmission and reception timings of a transceiver integrated ultrasonic sensor. Referring to FIG. 1, the transmission of the ultrasonic signal is repeated at regular intervals, and the interval needs to be spaced apart so as not to overlap the reception of the signal.

An ultrasonic sensor can be used to detect an object in front of the vehicle by installing it on the entry / exit path of the vehicle, such as an entrance of a parking lot, to detect entry of a vehicle or the like. For example, two ultrasonic sensors arranged side by side along the passage of the vehicle can be used to detect the approach direction of the vehicle. Each of the two ultrasonic sensors detects an object ahead according to its own setting. As the vehicle travels in the direction of traffic and the two sensors are arranged along the direction, when the vehicle enters the traffic lane, one of the two ultrasonic sensors will detect the vehicle first, The direction of travel can be determined.

On the other hand, the width of the corridor is considerably wide, so that the ultrasonic sensor installed on one side of the corridor may not detect the entire width of the corridor. In this case, it is necessary to install both sides of the corridor so that the vehicle passing through the wide corridor can be detected without missing.

The problem is that if the two ultrasonic sensors are arranged to face each other across the path, each ultrasonic sensor can receive the ultrasonic waves emitted by the opposing ultrasonic sensors arranged to face each other. This is because the ultrasonic sensor can effectively measure the flight time, but the ultrasonic wave emitted from the ultrasonic sensor can reach the opposite side of the path, relatively far away from the front.

Such direct reception of ultrasonic waves from other ultrasonic sensors interferes with the measurement of normal flight time, thus making it impossible to measure the distance of an object or confirm the entry of a vehicle based on the distance measurement.

[Related Prior Art]

Korean Utility Model Publication No. 20-1994-0006909 (Distance Recognition Circuit Using Ultrasonic Sensor)

It is an object of the present invention to provide a vehicle detecting apparatus and method for detecting a vehicle using a plurality of ultrasonic sensors by removing noise between a plurality of ultrasonic sensors by a synchronization technique to eliminate detection errors.

In order to attain the above object, a vehicle detecting apparatus according to the present invention is provided in a traffic passage to detect a traveling vehicle, and includes a plurality of integrated ultrasonic sensors, a timing controller, and a controller.

A plurality of integral type ultrasonic sensors are disposed in the passage in at least one pair to transmit and receive ultrasonic waves. The timing controller controls the plurality of ultrasonic sensors to simultaneously transmit ultrasonic waves in accordance with a synchronizing signal of a predetermined period, and the controller controls the reception signal of the plurality of ultrasonic sensors, On the basis of the detected vehicle. In the process of processing the received signal of the ultrasonic sensor, the controller can remove or ignore the ultrasonic wave received directly from the other ultrasonic sensor based on the synchronous signal, thereby eliminating the noise and preventing the detection error.

The ultrasonic sensor includes an oscillation element that emits and receives an ultrasonic wave, an oscillation unit that oscillates the oscillation element at a predetermined oscillation frequency, and a controller that processes the signal output from the oscillation element that receives the ultrasonic wave to output the reception signal .

According to an embodiment, the timing controller may control the simultaneous transmission of the ultrasonic waves by providing the synchronization signal to the oscillation units of the plurality of ultrasonic sensors.

According to another embodiment, the ultrasonic sensor may further include a switching unit provided between the oscillation unit and the oscillation unit and connecting the oscillation unit and the reception unit to the oscillation unit. In this case, the timing controller may control the switching unit of each of the plurality of ultrasonic sensors according to the synchronization signal to simultaneously transmit the ultrasonic waves.

In the embodiment in which the first ultrasonic sensor and the second ultrasonic sensor are arranged across the passage, the control unit performs the following mathematics based on the received signal provided from the first ultrasonic sensor and the second ultrasonic sensor after the synchronization signal, The width D of the vehicle can be obtained according to the equation.

Here, L is a distance between the first ultrasonic sensor and the second ultrasonic sensor, a is a distance between the first ultrasonic sensor and the vehicle measured by the first ultrasonic sensor, and b is a distance between the first ultrasonic sensor and the second ultrasonic sensor measured by the second ultrasonic sensor. It is a street.

The first reference time Tn may be calculated according to the following equation.

[sec] 및

[sec] and

[m/s]

[m / s]

Where L is the distance between two ultrasonic sensors disposed opposite each other across the path, T is the temperature in degrees Celsius, and Vu is the velocity of the ultrasonic waves.

The present invention also relates to a vehicle detection method of the above vehicle detection device. The vehicle detecting method of the present invention includes the steps of disposing at least one pair of integrated ultrasonic sensors on the passage, and controlling the timing controller to simultaneously transmit ultrasonic waves in accordance with a synchronizing signal of a predetermined cycle by the plurality of ultrasonic sensors And detecting the vehicle on the basis of the received signals received from the synchronous signal within the first reference time from the received signals of the plurality of ultrasonic sensors.

The vehicle detecting apparatus of the present invention can detect a vehicle using a plurality of ultrasonic sensors, measure the traveling direction of the vehicle, the width and speed of the vehicle, etc., and control the plurality of ultrasonic sensors based on one synchronizing signal So that the ultrasonic waves emitted from the plurality of ultrasonic sensors are outputted synchronously at the same time. With this synchronous control, the detection device can eliminate or ignore the noise generated by the ultrasonic wave directly received by the other ultrasonic sensor in the process of processing the received signal of the ultrasonic sensor. Naturally, detection errors can also be prevented.

Here, the plurality of ultrasonic sensors are basically applied to a pair of ultrasonic sensors disposed across the passage, and two or more pairs of ultrasonic sensors may be applied to the passage as required. In this case as well, it is possible to synchronously control the whole ultrasonic sensor of the detection device by one synchronous sensor, or to apply synchronous control to a pair of ultrasonic sensors by a separate synchronous signal. The diversity of such combinations is possible, and in any case, the signals received directly from other ultrasonic sensors through synchronous control can be suitably eliminated.

If two ultrasonic sensors are installed so as to face each other across at least the passage, and synchronous control is performed, errors such as signal interruption which may occur in one of the ultrasonic sensors can be corrected.

1 is a timing chart of ultrasonic emission and reception of a transceiver integrated ultrasonic sensor,
2 is a block diagram of a vehicle detection apparatus according to an embodiment of the present invention;
3 is a timing diagram for signal reception between the vibration elements of FIG. 2 as the vehicle passes;
4 is a timing diagram for signal reception between the first oscillating element and the second oscillating element of FIG. 2 in a state in which the vehicle does not pass,
5 is a timing diagram showing another example of signal reception between the first oscillation element and the second oscillation element in Fig. 2, and Fig.
6 is a block diagram of a vehicle detection apparatus according to another embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the drawings.

2, the vehicle detecting apparatus 200 includes a plurality of ultrasonic sensors 210, 230, 250, and 270, a timing controller 291, and a controller 293, The ultrasonic sensors 210, 230, 250 and 270 can detect the vehicle 10 entering the passage a and can measure the traveling direction of the vehicle, the width of the vehicle and the speed of the vehicle. have. Although the four ultrasonic sensors 210, 230, 250, and 270 are applied in FIG. 2, the present invention can be applied to a combination of two ultrasonic sensors as described below.

The ultrasonic sensors 210, 230, 250, and 270 applied to the vehicle detection apparatus 200 are integrated ultrasonic sensors that process the transmission and reception of ultrasonic waves by using one vibration element, and they may be arranged in any combination according to the purpose . However, since the synchronous control or synchronization method of the present invention is applied to a case where one pair of two ultrasonic sensors is arranged as a basic unit, the following description will focus on the case where at least one pair of two ultrasonic sensors are arranged. The pair of ultrasonic sensors may be arranged side by side along the passage a, or may be arranged across the passage a and may be arranged in such a manner that both the methods a and b are applied .

The method in which the vehicle 10 is arranged in a line along the passage a as in the method 1 does not only detect the vehicle 10 itself entering the passage a, but also detects the number of passages of the vehicle 10, the entry direction, May be detected. The manner in which the vehicle 10 is disposed across the passage a as in the method 2 can detect the type of the vehicle 10 by detecting the width of the vehicle 10 as well as detecting the vehicle 10 itself entering the passage a will be.

Since the arrangement of the method (1) and / or the method (2) defined by the present invention is a combination for noise elimination due to the direct reception of the opposite ultrasonic sensor, the arrangement is necessarily performed in such a manner that the outputs of the pair of ultrasonic sensors It is not limited to detecting the vehicle. In other words, each of the plurality of ultrasonic sensors can be designed so as to individually detect the front vehicle without considering the normal output of the other ultrasonic sensors.

The vehicle detecting apparatus 200 shown in FIG. 2 is an example in which both methods 1 and 2 are applied by arranging two pairs of ultrasonic sensors 210, 230, 250, and 270 across the passage a. Accordingly, the width of the vehicle 10 can be checked using the first ultrasonic sensor 210 and the second ultrasonic sensor 230, or the combination of the first ultrasonic sensor 210 and the third ultrasonic sensor 250, It is also possible to detect the approach direction of the vehicle 10 by using a combination of the ultrasonic sensor 230 and the fourth ultrasonic sensor 270. Meanwhile, the first to fourth ultrasonic sensors 210, 230, 250, and 270 may detect the vehicle individually or in different combinations. However, the first to fourth ultrasonic sensors 210, 230, 250, and 270 are arranged in a confronting manner so that the characteristic synchronous control of the present invention for eliminating interference that may occur between them is applied.

The first to fourth ultrasonic sensors 210, 230, 250, and 270 have the same configuration. Hereinafter, the structure of the first ultrasonic sensor 210 will be described on behalf of the first through fourth ultrasonic sensors 210, 230, 250, and 270. The first ultrasonic sensor 210 includes a first oscillation element 211, a first oscillation unit 213, a first reception unit 215, and a first signal processing unit 217.

The first oscillation element 211 not only transmits the ultrasonic waves forward under the control of the first oscillation unit 213 but also converts the ultrasonic waves received from the front into corresponding electric signals and provides them to the first reception unit 215. The first oscillation element 211 generates ultrasonic waves in accordance with a preset oscillation frequency, and the oscillation frequency of 40 kHz is mainly applied. However, there is no particular limitation on the oscillation frequency in the present invention.

Although the distance at which the measurement of the valid time of flight is guaranteed is limited to a certain extent, the ultrasonic waves emitted by the first oscillating element 211 can travel a considerable distance, at least up to the opposite side of the passage a. The ultrasonic waves output from the first oscillation element 211 can be received by the second oscillation element 231 even if the width of the passage a is large and the ultrasonic waves output from the second oscillation element 231 can also be received by the first The vibration element 211 can receive and interfere with each other. The present invention eliminates this interference through outgoing synchronization control.

On the other hand, the angle of emission of the ultrasonic waves output by the first oscillation element 211 is considerably limited, so that the possibility of reception by the third oscillation element 251 arranged in parallel is not enough to be considered.

The first oscillation unit 213 oscillates the first oscillation element 211 at a predetermined oscillation frequency. The first receiving unit 215 includes a band-pass filter (BPF) to filter the oscillation frequency component from the analog signal received and output by the first oscillation device 211, and the first signal processing unit 217, Converts the output of the first receiving unit 215 into a reception signal required for measurement of flight time using a low pass filter (LPF) or the like, and outputs the reception signal to the control unit 293.

The second ultrasonic sensor 230 includes a second oscillator 231, a second oscillator 233, a second receiver 235 and a second signal processor 237, The third oscillation unit 253 and the third reception unit 255 and the third signal processing unit 257. The fourth ultrasonic sensor 270 includes the fourth oscillation element 271, An oscillation unit 273, a fourth reception unit 275, and a fourth signal processing unit 277. Each of these operations is the same as that of the first ultrasonic sensor 210.

The timing controller 291 controls the operation timings of the plurality of ultrasonic sensors 210, 230, 250 and 270 under the control of the controller 293. [ Timing control of the timing controller 291 is defined by the present invention as synchronous control or synchronization and controls the plurality of ultrasonic sensors 210, 230, 250, and 270 to simultaneously transmit ultrasonic waves according to a synchronization signal of a predetermined period .

When a plurality of ultrasonic sensors 210, 230, 250, and 270 transmit ultrasonic signals at the same time by the timing controller 291, ultrasonic waves directly incident on the ultrasonic sensors other than the ultrasonic waves reflected from the object Noise) may be removed or at least not considered in the calculation of flight time. The operation related to the reception of the ultrasonic signals may be performed by the plurality of ultrasonic sensors 210, 230, 250, and 270, or may be performed by the controller 293. In a case where the timing controller 291 performs a control by a plurality of ultrasonic sensors 210, 230, 250, and 270, a control that does not receive ultrasonic waves directly incident from other ultrasonic sensors other than ultrasonic waves reflected from an object, And this control is also performed in the form of synchronous reception control in a plurality of ultrasonic sensors 210, 230, 250, and 270 as well.

If it is not synchronized, it can be very difficult to confirm whether the signal received right now is a reflected signal or a 'directly received signal'. Eventually, it becomes impossible to measure the flight time properly.

The synchronization signal may be provided from the control unit 293 or may be generated by the timing controller 291 according to a predetermined algorithm. Unless the timing controller 291 is implemented as programmable active hardware, it is preferable that a controller 293 capable of applying various synchronization control algorithms generates and provides a synchronization signal.

Since the timing controller 291 performs synchronous control on even-numbered ultrasonic sensors on the basis of the characteristics of the synchronous control of the present invention, the timing controller 291 can perform the synchronous control on all the ultrasonic sensors 210, 230, 250, and 270 It is not necessary to carry out the same control for the same. 2, the first and second ultrasonic sensors 210 and 230 and the third and fourth ultrasonic sensors 250 and 270 may perform different (or different) synchronism control. Alternatively, the first and third ultrasonic sensors 210 and 250 and the second and fourth ultrasonic sensors 230 and 270 may perform synchronous control at different (or different points in time).

The control unit 293 detects the vehicle, the width of the vehicle 10, the traveling direction and the speed of the vehicle on the basis of the received signals of the plurality of ultrasonic sensors 210, 230, 250 and 270. Hereinafter, a vehicle detection method of the control unit 293 will be described with reference to FIG. 3 is a timing diagram for signal reception between the vibration elements 211, 231, 251, and 271 of FIG. 2 when the vehicle passes through, and the horizontal axis is time (t) axis.

First, the detection of the vehicle can detect the entry of the vehicle when the calculated flight time according to passage of the vehicle 10 is within a certain range.

The width D of the vehicle uses two ultrasonic sensors facing each other based on the passage (a). 3 (a), the first oscillation element 211 of the first ultrasonic sensor 210 and the second oscillation element 231 of the second ultrasonic sensor 230 are synchronously controlled so that the signal X1 and Y1 are transmitted. Here, since the expression of the signals X1 and Y1 is only for the division in FIG. 3, it is not based on the premise that the signals transmitted from the first oscillation element 211 and the second oscillation element 231 are different from each other. In other words, the signals transmitted by the first oscillation element 211 and the second oscillation element 231 may be equal to each other.

If the vehicle 10 passes, the first oscillating element 211 receives the signal X1 'reflected from the vehicle 10 after the Tm1 flight time, and the second oscillating element 231 receives the signal X1' Lt; RTI ID = 0.0 > Y1 '< / RTI > The difference in flight time is common because the vehicle 10 is not in the middle of the traffic route (a). Therefore, the control unit 293 can calculate the width of the vehicle using Equation (2) and Equation (3) based on the flight times Tm1 and Tm2.

Where L is the distance between the first oscillating element 211 of the first ultrasonic sensor 210 and the second oscillating element 231 of the second ultrasonic sensor 230, B is a distance between the second ultrasonic sensor 230 and the vehicle 10. The distance between the second ultrasonic sensor 230 and the vehicle 10 is the distance between the sensor 210 and the vehicle 10, a and b can be obtained by substituting the flight times Tm1 and Tm2 in the first ultrasonic sensor 210 and the second ultrasonic sensor 230 when the vehicle 10 passes through equations (1) and (2).

The traveling direction and the speed of the vehicle 10 can be obtained by using two ultrasonic sensors arranged side by side along the passage a. When the vehicle enters in a state in which two ultrasonic sensors are arranged side by side along the passage (a), the speed of the ultrasonic waves is much faster than the entry speed of the vehicle, so that one of the two ultrasonic sensors is at least fewer than the rest of the ultrasonic sensors You can find the vehicle early enough. The entry direction of the vehicle can be determined by which ultrasonic sensor first recognizes the vehicle, and the speed of the vehicle can be roughly obtained by the time difference of the recognition time.

In the example of FIG. 3B, the first oscillating element 211 of the first ultrasonic sensor 210 and the third oscillating element 251 of the third ultrasonic sensor 250 are synchronously controlled so that ultrasonic waves X1 and X2, and the transmission of these ultrasonic waves X1 and X2 is repeated in the same cycle. The ultrasonic wave X1 'is a signal that the ultrasonic wave X1 is reflected by the vehicle 10 and is received by the first oscillation element 211. The ultrasonic wave X2' 231). The hatched bar is a visual indication of the period of time that the first ultrasonic sensor 210 and the third ultrasonic sensor 250 recognized the vehicle 10, respectively.

The speed of the ultrasonic waves is remarkably faster than the speed of the vehicle 10 so that the first and second vibrating elements 211 and 251 can recognize the vehicle 10 continuously for a period corresponding to a plurality of periods have. 3 (b), the distance between the first oscillating element 211 and the third oscillating element 251 and the speed of the vehicle 10 cause the first oscillating element 211 to contact the third oscillating element 251), the vehicle 10 is recognized at a time corresponding to three cycles. Therefore, it can be confirmed that the vehicle 10 has entered the direction from the first vibration element 211 to the third vibration element 251. The approach direction of the vehicle can be determined by which ultrasonic sensor recognizes the vehicle first. It is possible to calculate the approximate speed by the difference between the time (or the calling interval) in which the first oscillation element 211 and the third oscillation element 251 recognize the vehicle 10.

On the other hand, when the first ultrasonic sensor 210 recognizes the vehicle 10 after the third ultrasonic sensor 250 first recognizes the vehicle 10, the third ultrasonic sensor 250 proceeds to the first ultrasonic sensor 210 The vehicle 10 enters the direction in which the vehicle 10 travels.

As described above, the ultrasonic sensors (for example, the first ultrasonic sensor and the second ultrasonic sensor in Fig. 2, or the third ultrasonic sensors in Fig. 2) arranged in opposition to each other in the checking of the vehicle, the calculation of the width of the vehicle, A signal transmitted from the ultrasonic sensor disposed on the opposite side of the passage a may be directly received instead of receiving the signal reflected from the vehicle ahead in the first ultrasonic sensor and the fourth ultrasonic sensor. However, the problem of direct reception of such a signal can be effectively eliminated in the present invention.

Elimination of noise based on synchronous control

The control unit 293 may directly receive a signal that may occur between the ultrasonic sensors disposed to face each other (e.g., the first ultrasonic sensor and the second ultrasonic sensor in Fig. 2 or the third ultrasonic sensor and the fourth ultrasonic sensor) Can be eliminated through synchronous control. As described above, the synchronization control can also be performed by the timing controller 291 instead of the control unit 293. [

4 is a timing diagram for signal reception between the first ultrasonic sensor 210 and the second ultrasonic sensor 230 when the vehicle does not enter. When the first oscillating element 211 and the second oscillating element 231 transmit the signal X1 and the signal Y1 at the same time by the synchronous control, the first oscillating element 211 and the second oscillating element 231, respectively, The signals transmitted from the first oscillation element 211 and the second oscillation element 231 are made incident on the ultrasonic sensor opposite to the first reference time Tn after the elapse of the first reference time Tn .

Therefore, a signal received over the first reference time Tn may be determined as a 'directly received' signal and removed. The first reference time Tn can be obtained by the following equation (4).

Here, Vu is the velocity of the ultrasonic wave, and L is the distance between the vibration elements of the mutually facing ultrasonic sensors. For example, L may be a distance between the first oscillating element 211 and the second oscillating element 231, or may be a distance between the third oscillating element 251 and the fourth oscillating element 271 .

The basis of the determination using the first reference time Tn is synchronous control. It is presupposed that the first oscillation element 211 and the second oscillation element 231 transmit ultrasonic waves at the same time point by the synchronization signal of the timing controller 291. [ Thereafter, the controller 293 or the timing controller 291 does not receive the signal at the time when the first reference time Tn elapses from the synchronization signal or does not apply the received signal to the calculation of the flight time.

According to the embodiment, the controller 293 may set a signal reception blocking period within a predetermined time range from the synchronization signal, as shown in FIG. The blocking period may be set to a certain range including the first reference time. Naturally, the transmission period of FIG. 1 is set longer than the first reference time, and the blocking period should be set within the transmission period.

The control unit 293 can remove noise in a form of filtering or ignoring noise received in the blocking period and provides a control signal corresponding to the blocking period to the timing controller 291 so that the timing controller 291 So that the receiving unit and the signal processing unit can not perform the signal receiving operation.

By the above-described synchronous control, it is possible to remove noise due to direct reception from the received signal.

Example 1

The ultrasonic sensor may cause a signal interruption in which the output of the ultrasonic sensor does not coincide with the passage of the vehicle 10 due to the use environment, the shape of the vehicle, or the performance of the sensor itself.

5 is a timing chart showing another example of signal reception between the first oscillation element 211 and the second oscillation element 231 in FIG. 2, and the horizontal axis is time (t) axis. For example, in FIG. 5, according to the output of the first ultrasonic sensor 210, it is understood that two vehicles have entered, or all or a part of the signal may be processed as noise.

However, according to the present invention, by performing synchronous control on the first ultrasonic sensor 210 and the second ultrasonic sensor 230, the controller 293 confirms that the signal disconnection of the first ultrasonic sensor 210 is in an error state The reception error of the first oscillation element 211 can be corrected.

Example 2

In the above description, the timing controller 291 performs synchronization control on the first to fourth ultrasonic sensors 210, 230, 250 and 270 with one synchronizing signal. However, the timing controller 291 sets the first ultrasonic sensor 210 and the third ultrasonic sensor 250 as one group, sets the second ultrasonic sensor 230 and the fourth ultrasonic sensor 270 as one group, The two groups may be synchronously controlled separately.

Example 3

6 shows a vehicle detection apparatus 600 according to another embodiment of the present invention. Each of the ultrasonic sensors 610, 630, 650, and 670 applied to the vehicle detection apparatus 600 includes switching units 601, 603, 605, and 607 in addition to the ultrasonic sensors 210, 230, .

The timing controller 291 may control the switching units 601, 603, 605, and 607 to control signals to be transmitted at the same time, or may control not to receive signals during the blocking period.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.

Claims (11)

A vehicle detection device for detecting a vehicle provided on a traffic passage and passing through the vehicle,
A plurality of monolithic ultrasonic sensors each transmitting and receiving ultrasonic waves (the ultrasonic sensors are arranged on both sides of the corridor with pairs of two to emit ultrasonic waves toward the corridor);
A timing controller for controlling the plurality of ultrasonic sensors to simultaneously transmit ultrasonic waves according to a synchronization signal of a predetermined period; And
And a controller for detecting the vehicle based on the received signals received within a first reference time from the synchronized signal among the received signals of the plurality of ultrasonic sensors.
The method according to claim 1,
Wherein the timing controller controls the ultrasonic sensors to simultaneously transmit the ultrasonic waves by providing the synchronization signals to the oscillation units of the plurality of ultrasonic sensors.
The method according to claim 1,
The ultrasonic sensor includes:
A vibrating element for transmitting and receiving ultrasonic waves;
An oscillation unit for oscillating the oscillation element at a predetermined oscillation frequency;
A receiver for processing the signal output from the ultrasonic transducer and outputting the received signal; And
And a switching unit provided between the oscillation unit and the oscillation unit to connect one of the oscillation unit and the reception unit to the oscillation unit,
Wherein the timing controller controls the switching unit of each of the plurality of ultrasonic sensors according to the synchronization signal to simultaneously transmit the ultrasonic wave.
The method according to claim 1,
Wherein the plurality of integrated ultrasonic sensors include a first ultrasonic sensor and a second ultrasonic sensor arranged to face each other across the path,
The controller calculates the width D of the vehicle according to the following equation based on the received signal received from the first ultrasonic sensor and the second ultrasonic sensor after the synchronization signal,

L is a distance between the first ultrasonic sensor and the second ultrasonic sensor, a is a distance from the vehicle measured by the first ultrasonic sensor, and b is a distance from the vehicle measured by the second ultrasonic sensor And the vehicle detection device.
The method according to claim 1,
The first reference time Tn is calculated according to the following equation,

[sec] and

[m / s]
L is a distance between two ultrasonic sensors arranged to face each other across the passage, T is the temperature (占 폚), and Vu is the velocity of the ultrasonic wave.
The method according to claim 1,
Wherein the timing controller sets a predetermined period including a time point at which the first reference time ends, as a blocking period, and does not receive a signal,
The first reference time Tn is calculated according to the following equation,

[sec] and

[m / s]
L is a distance between two ultrasonic sensors arranged to face each other across the passage, T is the temperature (占 폚), and Vu is the velocity of the ultrasonic wave.
A vehicle detecting method of a vehicle detecting apparatus which detects a vehicle which is provided on a traffic passage and which is passing through,
Disposing a plurality of integral type ultrasonic sensors on both sides of the passage (the two ultrasonic sensors are arranged on both sides of the passage so as to emit ultrasonic waves toward the passage)
Controlling the timing controller so that the plurality of ultrasonic sensors transmit ultrasonic waves simultaneously according to a synchronizing signal of a predetermined period; And
And the control unit detects the vehicle based on the received signals received from the synchronous signal within the first reference time among the received signals of the plurality of ultrasonic sensors.
8. The method of claim 7,
Wherein the timing controller controls the ultrasonic sensors to simultaneously transmit the ultrasonic waves by providing the synchronization signals to the oscillation units of the plurality of ultrasonic sensors.
8. The method of claim 7,
Wherein the first ultrasonic sensor and the second ultrasonic sensor are disposed across the passage in the step of disposing the ultrasonic sensors on both sides of the passage,
The controller calculates the width D of the vehicle according to the following equation based on the received signal received from the first ultrasonic sensor and the second ultrasonic sensor after the synchronization signal,

L is a distance between the first ultrasonic sensor and the second ultrasonic sensor, A is a distance from the vehicle measured by the first ultrasonic sensor, and B is a distance between the first ultrasonic sensor and the second ultrasonic sensor measured by the second ultrasonic sensor Wherein the vehicle detecting device detects the vehicle.
8. The method of claim 7,
The first reference time Tn is calculated according to the following equation,

[sec] and

[m / s]
L is a distance between two ultrasonic sensors arranged to face each other across the passage, T is the temperature (占 폚), and Vu is the velocity of the ultrasonic wave.
8. The method of claim 7,
Wherein the timing controller sets a predetermined period including a time point at which the first reference time ends, as a blocking period, and does not receive a signal,
The first reference time Tn is calculated according to the following equation,

[sec] and

[m / s]
L is a distance between two ultrasonic sensors arranged to face each other across the passage, T is the temperature (占 폚), and Vu is the velocity of the ultrasonic wave.

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