JPH0763847A - Device of detector object - Google Patents

Abstract

PURPOSE:To obtain a device of detecting an object which can surely detect whether the object is present. CONSTITUTION:A detecting device of an object comprises an ultrasonic wave circuit 1 and a determination circuit 2, roughly divided. An ultrasonic wave signal generating circuit 13 sends out an ultrasonic pulse signal only during a period of a transmission signal from a transmission pulse generating circuit 12. This ultrasonic pulse signal is given to an ultrasonic oscillator 15 through a transmission amplifying circuit 14. The ultrasonic oscillator 15 sends out an ultrasonic wave into a specified area. The ultrasonic oscillator 15 receives a reflected wave and gives it to a reception amplifying circuit 16 and a detection circuit 17. The determination circuit 2 compares the pulse pattern of the ultrasonic pulse signal sent out from the ultrasonic circuit 1 with that of a reflected wave signal. When these patterns do not coincide with each other, it specifies the reflected wave signal not being coincident and determines the presence of the object or an environmental change on the basis of comparison with the pulse pattern of the reflected wave thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object detecting device using ultrasonic waves, and more particularly to an object detecting device which can reliably detect the presence or absence of an object outdoors without being affected by a disturbance such as wind and rain.

[0002]

2. Description of the Related Art Generally, a parking system is often provided with a breaker. In this case, as shown in FIG. 6, the circuit breaker 101 includes a circuit breaker main body 102 and the main body 1
When it is composed of a bar 103 that is rotatably fixed to 02, if an object such as an automobile 104 exists directly below the bar 102, an accident may occur. Therefore, conventionally, various types of object detection devices have been used to
The presence of an object such as the automobile 104 within the length of 02 is detected to prevent the above-described accident.

As the above-mentioned object detecting device, there are provided a device using light, a device using infrared rays in the light, a device using ultrasonic waves, etc., but it is used only by mounting the device in one place. Ultrasonic sensors that can be used at present are often used. An object detection device using such an ultrasonic wave emits an ultrasonic wave toward a predetermined area,
It is a device that detects whether or not an object exists in a predetermined area by the reflected wave.

As described above, in the case of an object detecting device using ultrasonic waves, when there is a specific reflected wave from the detection area, it is determined that an object exists.

[0005]

As described above, in the object detecting device using ultrasonic waves, a reflected wave may be formed in a specific area due to changes in the natural environment such as rain and wind. Therefore, there is a drawback in that it often determines that there is an object even though there is no object in the area, and that malfunction often occurs. It is an object of the present invention to solve the above-mentioned drawbacks and to provide an object detection device capable of surely detecting the presence or absence of an object.

[0006]

In order to achieve the above object, the object detecting device of the present invention sends an ultrasonic wave to a specific area and judges whether or not there is an object in the specific area by the reflected wave. In the object detection device, the ultrasonic pulse signal at a constant time interval is applied to the ultrasonic oscillator for the period of the transmission signal and is transmitted within a specific area, and the reflected wave is received by the ultrasonic oscillator and pulsed. The ultrasonic circuit that forms the reflected wave signal and the pulse pattern of the transmitted ultrasonic pulse signal and the reflected wave signal from the ultrasonic circuit are compared, and when these do not match, the reflected wave signal that does not match is specified. And a determination circuit that compares the specified pulse pattern of the reflected wave with a constant reference value to determine that the change is an object or environment.

[0007]

Since the present invention is configured as described above, pulsed ultrasonic waves are emitted to a specific area, pulsed reflected waves are received, and the pulse patterns of both are compared. In addition, it is determined that there is an environmental change such as an object or wind and rain, and the object or the environmental change is specified by the pulse pattern of the reflected wave.

[0008]

The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a block diagram showing an embodiment of an object detection device according to the present invention. The object detection device shown in FIG. 1 is roughly divided into an ultrasonic circuit 1 and a determination circuit 2.

The ultrasonic circuit 1 generates an ultrasonic pulse signal which is turned on and off at a constant time interval and emits it as a pulsed ultrasonic wave in a predetermined space area, and the generated ultrasonic pulse signal and a predetermined ultrasonic wave signal. It is a circuit that can convert the reflected wave reflected from the spatial region into an electric signal and output it.

Further, the judging circuit 2 takes in the electric signal from the ultrasonic circuit 1, matches the emitted pulse signal with the pulse pattern of the reflected wave signal reflected, and if they do not match, the pattern of the reflected wave signal is detected. It is a circuit that checks and determines whether it is an object or a disturbance.

More specifically, the ultrasonic circuit 1
Is a gate signal generation circuit 11 and a transmission pulse generation circuit 1
2, an ultrasonic signal generation circuit 13, and a transmission amplification circuit 14
And an ultrasonic oscillator 15, a reception amplification circuit 16, and a detection circuit 17. That is, the gate signal generation circuit 11
Is a circuit that generates a gate signal, and is connected to the input terminals of the transmission pulse generation circuit 12 and the detection circuit 17. The transmission pulse generation circuit 12 is a circuit that generates a transmission signal for a fixed time T when a gate signal is input,
The transmitted signal can be supplied to the ultrasonic signal generation circuit 13. The ultrasonic signal generation circuit 13 is a circuit that can generate an ultrasonic pulse signal that is turned on and off at fixed time intervals and that can output a predetermined number of ultrasonic pulse signals only when the transmission signal is input. The output ultrasonic pulse signal can be supplied to the transmission amplification circuit 14. The transmission amplification circuit 14 can amplify the ultrasonic pulse signal and supply it to the ultrasonic oscillator 15. The ultrasonic oscillator 15 is an element capable of converting the supplied ultrasonic pulse signal into pulsed ultrasonic waves and emitting the ultrasonic waves in a specific space region. Further, the ultrasonic oscillator 15 can convert a reflected wave reflected from a specific space area into an electric signal and supply the electric signal to the reception amplification circuit 16. The reception amplification circuit 16 is a circuit for amplifying the supplied reflected wave signal, and the amplified reflected wave signal can be supplied to the detection circuit 17. The detection circuit 17 is a circuit that detects a reflected wave signal. The gate signal from the gate signal generation circuit 11 is input so as to prevent detection while the ultrasonic signal is being oscillated.

The determination circuit 2 is composed of a computer device. That is, the computer device comprises a central processing unit (CPU), a memory (RAM), a read only memory (ROM), an input / output device (I / O), an analog / digital converter (A / D converter), etc. ROM
The operation of the ultrasonic circuit 1 is controlled in accordance with a predetermined program stored in, and the electric signal from the ultrasonic circuit 1 is taken in. It is possible to determine whether or not the result is output to the outside. Further, the signals from the gate signal generation circuit 11, the transmission pulse generation circuit 12, and the ultrasonic signal generation circuit 13 are taken in and added to the determination element, and at the same time, the detection reference of the detection circuit 17 can be controlled.

The operation of the embodiment thus configured is shown in FIG.
2 will be described with reference to FIGS. Figure 2
3 is a flow chart for explaining the operation of the embodiment. FIG. 3 is a time chart for explaining the operation of the embodiment, in which the horizontal axis shows time (t [seconds]) and the vertical axis shows signals of the respective parts. 4 and 5 are explanatory diagrams for explaining the detection state of the object.

First, the gate signal generation circuit 11 outputs a gate signal at regular time intervals. This gate signal (FIG. 3A) is supplied to the input terminals of the transmission pulse generation circuit 12 and the detection circuit 17. When the gate signal is input to the transmission pulse generation circuit 12, the transmission pulse generation circuit 1
2 outputs a transmission signal of a constant time T as shown in FIG. 3 (b). This transmitted signal is supplied to the ultrasonic signal generation circuit 13. The ultrasonic signal generation circuit 13 generates an ultrasonic pulse signal that turns on and off at regular intervals.
When the transmission signal as shown in (c) is supplied, the ultrasonic pulse signal is output for the time T of the transmission signal. This ultrasonic pulse signal is amplified by the transmission amplifier circuit 14 and supplied to the ultrasonic oscillator 15. The ultrasonic oscillator 15 is excited by the ultrasonic pulse signal, and sends pulsed ultrasonic waves to a specific space area (for example, an area where the bar of the circuit breaker is positioned horizontally).

On the other hand, the ultrasonic pulse signal from the transmission amplification circuit 14 is subjected to waveform shaping and detection by the detection circuit 17 via the reception amplification circuit 16.

<When it is determined that there is no object in the specific space> Here, when there is no object in the specific space area, a transmission pulse signal as shown in FIG. 4B is ultrasonically oscillated. When the ultrasonic wave is transmitted to a predetermined space through the child 15, the ultrasonic waves are reflected by the surrounding buildings including the space. When the reflected wave is received by the ultrasonic oscillator 15, the ultrasonic oscillator 15 Generates almost no electric signal, as shown in FIG. Therefore, no signal is generated in the detection circuit 17, and it is determined that there is no object.

Although the description so far has been on a general ultrasonic measurement method, ultrasonic waves are generated by ultrasonic waves generated by the ultrasonic oscillator 15 due to rain, wind, etc., even though there is no object. It may be received by the child 15. Judgment circuit 2
Takes in the ultrasonic pulse signal of the ultrasonic signal generation circuit 13. Next, while the gate signal generation circuit 11 is outputting a pulse signal, the pulse of the reflected wave is taken in from the detection circuit 17. Then, in the determination circuit 2, the pulse pattern of the transmitted ultrasonic pulse signal shown in FIG.
The pulse pattern of the reflected wave signal shown in (e) is matched. In the determination circuit 2, by matching the patterns of the signals, it is determined by what percentage of probability the match is made, and it is determined whether or not the object exists in the specific space.

<When it is determined that an object is present in a specific area> When an object is present in the specific area, FIG.
When a transmission pulse signal as shown in (1) is transmitted to a predetermined space through the ultrasonic oscillator 15, the ultrasonic waves are reflected by an object in the space area. This reflected wave is the ultrasonic oscillator 1
5, the ultrasonic oscillator 15 generates a signal as shown in FIG. 5 (c). The detection circuit 17 detects the waveform only during the period when the signal from the gate signal generation circuit 11 is output.

Even if there is an object in a specific area, rain,
The reflected waves of the ultrasonic waves oscillated by the ultrasonic oscillator 15 due to the wind or the like have many influences. The determination circuit 2 takes in the ultrasonic pulse signal of the ultrasonic signal generation circuit 13. next,
The pulse of the reflected wave is taken in from the detection circuit 17 while the gate signal generation circuit 11 is outputting the pulse signal. Then, the determination circuit 2 matches the pulse pattern of the transmitted ultrasonic pulse signal shown in FIG. 5 (b) with the pulse pattern of the reflected wave signal shown in FIG. 5 (e). The determination circuit 2 determines by what percentage of probability the signals are matched by matching the signal patterns, and determines whether or not an object exists in a specific area.

When there is no object to be detected, the ultrasonic signal reflected by rain, dust, etc. is the signal of the detection circuit 17 shown in FIG.
As in (b), the pulse numbers do not match. It is determined that there is no object when the number of pulses is less than a certain ratio. Also, when there is a lot of rain, it is assumed that there will be many reflected waves, so automatic adjustment of the sample level in the detection circuit will be performed based on the reflected wave pattern of the ultrasonic waves emitted several times before. I do. This is based on the assumption that a sudden change in the reflected wave pattern due to the influence of the environment does not occur. When the detected object is present, a lot of signals such as rain and dust are included before the detected object signal like the received signal of FIG. 8B, but these reflected wave signals are several times before. It can be removed based on the reflected wave pattern of the ultrasonic waves emitted to the. Therefore, the accurate position of the object can be measured. As described above, in this embodiment, the determination circuit 2 constantly learns the information of the pattern of the reflected wave from the object, controls the inspection standard,
Moreover, since unnecessary reflected waves are removed, it is possible to reliably detect an object.

Although the above embodiment has been described with reference to the example applied to the breaker of the parking lot system, the present invention is not limited to this.
It can be applied to a device that detects the presence or absence of an object outdoors or in a place where dust or the like is generated.

[0022]

As described above, according to the present invention, ultrasonic pulses at a constant interval are emitted to a specific area, a change in the reflected wave is detected by comparing the reflected wave with an ultrasonic pulse train, and the reflected wave is reflected. Since the presence / absence of an object or the environmental change is detected from the crest value and frequency of the wave, there is an effect that the presence / absence of an object can be reliably detected even in a poor environment environment.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an object detection device of the present invention.

FIG. 2 is a flow chart for explaining the operation of the embodiment.

FIG. 3 is a time chart for explaining the operation of the embodiment.

FIG. 4 is a time chart for explaining an operation when there is no object.

FIG. 5 is a time chart for explaining a specific example of an operation due to the presence of the same object or a change in environment.

FIG. 6 is an explanatory diagram showing a circuit breaker of a parking lot system.

FIG. 7 is a time chart for explaining an operation when there is no detected object.

FIG. 8 is a time chart for explaining the operation when a detected object is present.

[Explanation of symbols]

 1 Ultrasonic Circuit 2 Judgment Circuit 11 Gate Signal Generation Circuit 12 Transmitted Pulse Generation Circuit 13 Ultrasonic Signal Generation Circuit 14 Transmission Amplification Circuit 15 Ultrasonic Oscillator 16 Reception Amplification Circuit 17 Detection Circuit

Claims (1)

[Claims] 1. An object detection device for transmitting an ultrasonic wave to a specific area and determining whether or not an object is present in the specific area based on the reflected wave of the ultrasonic wave. An ultrasonic circuit that gives an ultrasonic wave oscillator a specific period of time and sends it out within a specific region, and receives a reflected wave with the ultrasonic wave oscillator to form a pulsed reflected wave signal; and an ultrasonic wave sent from the ultrasonic circuit. Compare the pulse patterns of the sound wave pulse signal and the reflected wave signal, and when they do not match, identify the reflected wave signal that does not match, compare the identified reflected wave pulse pattern with a certain reference value, and An object detection device, comprising: a determination circuit for determining that the environment has changed.