JPH03216785A - Moving object detecting device - Google Patents

Abstract

PURPOSE:To obtain a moving object detecting device with which an accurate sound reporting action is secured by inhibiting the new reporting sounds for a fixed period after detecting a human body, etc., and a reporting sound is started and updating the start inhibiting period of the new reporting sounds every time the human body, etc., are newly detected during the inhibiting period. CONSTITUTION:A sound report control circuit CR controls the sound reporting actions of a sound report circuit SD and consists of a retriggerable one-shot multivibrator. The new reporting sounds are never started as long as the one- shot pulses are produced from the circuit CR. Furthermore these one-shot pulses are retriggerable. Thus the new reporting sounds are never substantially pro duced even when many persons are continuously moving. Then the accurate sound reporting actions are ensured with a moving object detecting device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a moving object detection device for detecting the moving direction of a person or the like.

[Prior Art] Conventionally, there has been a detection device that detects the moving direction of a person, object, etc. and generates a notification sound according to the moving direction. for example,
If this detection device is installed in front of a store, when a person enters the store, the message "Welcome" will be displayed. ], and when people leave the store they say, ``Thank you very much.''

When detecting the normal movement direction, two sensors DTI1 and DT are used as shown in FIGS.
12 is used for detection. That is, sensor DT
II and DT12 sense mutually different areas, and for example, when sensor DT11 first detects a moving object, it is determined that the moving object is moving from the bottom to the top of the drawing.

[Problem to be Solved] The conventional moving object detection device described above has a problem when, for example, a large number of people move continuously. This problem will be explained using FIGS. 6(A) and 6(B). First, the 6th
As shown in Figure (A), when the person Mll is detected by the sensor DTII, it is assumed that the person Mll is entering the store, and the audible device issues a sound saying "Welcome." If only the person M11 moves, he will also pass through the sensing area of the sensor DT12 during the warning sound.
No particular problem arises. This is because even if a new detection is made during a warning sound, a new warning sound will not be started.

However, when a large number of people move continuously,
As shown in FIG. 6(B), a person M13 may be present in the sensing area of the sensor DT12 after the sound of "Welcome" is sounded. In such a case, person M1
Even though 3 is trying to enter the store, it is mistakenly assumed that he is leaving the store, and the alarm system calls out "
thank you very much. ” will be announced.

An object of the present invention is to obtain a moving object detection device that performs an accurate alarm operation.

[Means for Solving the Problems] The present invention prohibits new activation of the notification sound for a certain period of time after detecting a human body or the like and activating the notification sound, and when a human body or the like is newly detected during this prohibition period. The prohibition period will be updated each time.

[Example] Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment.

SN is a sensor circuit that detects a moving object. The configuration of this sensor circuit SN is as shown in FIG. PEI and PE2 are pyroelectric infrared sensors,
The pyroelectric bodies are arranged so that their polarization directions are opposite to each other.

RG is a resistor for discharging, and AP is an amplifier. The operation of the circuit shown in FIG. 2 will be explained using FIG. 3.

For example, when the moving body moves from the top to the bottom of the drawing (direction L in FIG. 2), the following is the case. First, when a moving body (not shown) such as a human enters the detection range (first detection range) of the pyroelectric infrared sensor PEI, a change in infrared rays generated from the moving body is sensed and polarized to the positive side. continuation,
When a moving object enters the detection range (second detection range) of the pyroelectric infrared sensor PE2, the pyroelectric infrared sensor PE2, which is connected with the opposite polarity to the pyroelectric infrared sensor PEI, detects a change in infrared light. and polarizes to the negative side. Therefore, the signal waveform (a) output to the amplifier AP is as shown in FIG. 3(A). Conversely, when the moving body moves from the bottom to the top of the drawing (direction R in Fig. 2), the signal waveform (a) is
The result will be as shown in Figure (B). In this way, different signal waveforms are obtained depending on the moving direction of the moving body.

CP1 and CP2 are comparators that convert the output signal from the sensor circuit SN into reference voltages "Vl" and "v2".
In comparison, the first detection signal and the second detection signal are respectively output.

The detection circuit D is detected by the comparators CPI and CP2.
T is constructed.

Dll and DI2 are diodes.

SL is a selection circuit that selects whether a sound alarm circuit SD, which will be described later, generates a first alarm signal or a second alarm signal. This selection circuit SL is composed of an RS flip-flop, and the output of the comparator CPI is connected to the set input "S", and the output of the comparator CP2 is connected to the reset input "R".

CR is a sound control circuit, which controls the sound operation of a sound sound circuit SD, which will be described later. This alarm control circuit CR is composed of a retriggerable one-shot multi-by-break circuit.

SD is a sound alarm circuit, which receives output signals from the selection circuit SL and the sound alarm control circuit CR and outputs a first alarm signal or a second alarm signal.

MHI and MR2 are storage circuits, which are configured with read-only memories. These memory circuits MR1 and MR
2 stores the patterns of the first notification signal and the second notification signal output from the sound notification circuit SD, respectively.

SP is a speaker, which receives the first notification signal or the second notification signal output from the notification sound circuit SD and reports the first notification sound or the second notification sound.

Next, the operation of this embodiment will be explained with reference to FIGS. 4 and 5.

Note that FIGS. 4 a to 4 e show signal waveforms at a to e in FIG. 1.

First, as shown in FIGS. 5(A) and 5(B), consider the case where moving bodies M1 and M2 such as humans move from the top to the bottom of the drawing.

As shown in FIG. 5(A), the moving body M1 is connected to the sensor PEI.
When entering the detection range (first detection range), Fig. 4(a)
As shown in the figure, a positive displacement output is obtained from the sensor circuit SN. Upon receiving this output signal, the comparator CP
A first detection signal is output from I. This first detection signal is input to the alarm control circuit CR through the diode Dll (b), and a one-shot pulse (C) of a fixed period is generated from the alarm control circuit CR. The setting time of this one-shot pulse is within the detection range of sensor PEI (
It is set longer than the time required to move from the first detection range) to the detection range of the sensor PE2 (second detection range). Furthermore, this set time is set longer than the time during which the first or second notification signal is occurring. The rising edge of the one-shot pulse activates the alarm circuit SD.

The output terminal "Q゜" of the selection circuit SL is connected to the alarm circuit SD, but since the selection circuit SL is in the set state upon receiving the first detection signal, the output terminal "Q゜" of the selection circuit SL is connected to the output terminal "Q゜" of the selection circuit SL. "1" is output from the selection circuit SL. That is, when the sound alarm circuit SD receives the one-shot pulse, "1" is input to the sound alarm circuit SD from the selection circuit SL.

As a result, the first notification sound is selected in the sound circuit SD, and the first notification signal pattern is sent from the memory circuit MR1 to the sound circuit SD (d). In response to this first notification signal pattern, a first notification signal is output from the sound circuit SD, and a first notification sound, for example, "Welcome!" is announced from the subica SP. Subsequently, the moving object M2 is within the detection range of sensor PEI (first detection range)
As shown in FIG. 4(a), the sensor circuit SN
Again, a positive displacement output is obtained.

In response to this output signal, the comparator CP1 outputs the first detection signal again. This first detection signal is
The signal is input to the alarm control circuit CR through the diode Dll, and the alarm control circuit CR retrigger the one-shot pulse. Since the alarm circuit SD is activated at the rising edge of the one-shot pulse, the first alarm sound is not affected in any way. That is, the retriggerable one-shot pulse generated by the alarm sound control circuit CR functions as an activation inhibit signal for the first alarm sound and the second alarm sound described later.

Subsequently, as shown in FIG. 5(B), when the moving objects M1 and M2 enter the detection range (second detection range) of sensor PE2, as shown in FIG. , a continuous negative displacement output is obtained. In response to this output signal, the second
A detection signal is output. This second detection signal is input to the alarm control circuit CR through the diode DI2 (b
), the one-shot pulse is retriggered in the alarm control circuit CR (C). Since the alarm circuit SD is activated at the rising edge of the one-shot pulse, the second alarm sound is not generated and the first alarm sound is not affected in any way.

After the first notification sound operation ends, the retriggerable one-shot pulse falls. The retriggerable one-shot pulse falls after a certain period of time has elapsed since the fourth pulse shown in FIG. 4(b) was generated.

Next, after the retriggerable one-shot pulse falls, the moving object M
Consider the case where 3 moves from the bottom to the top of the drawing.

As shown in FIG. 5(C), the moving body M3 is connected to the sensor PE2.
When the detection range (second detection range) is entered, the second detection signal is output from the comparator CP2 in the same manner as the operation described above. As a result, a one-shot pulse (c) is generated from the alarm control circuit CR, and the alarm circuit SD is activated by the rise of the one-shot pulse (c). Since the selection circuit SL is in the reset state upon receiving the second detection signal, "0" is output from the output terminal "Q" of the selection circuit SL.

Therefore, the second notification sound is selected in the sound circuit SD, and the second notification signal pattern is sent from the memory circuit MR2 to the sound circuit SD (e). In response to this second notification signal pattern, a second notification signal is output from the sound circuit SD, and a second notification sound, for example, "Thank you." is announced from the speaker SP. The subsequent operations are almost the same as those already described.

As can be seen from the operations described above, while a one-shot pulse is being generated from the alarm sound control circuit CR, a new alarm sound is not activated, and since the one-shot pulse is retriggerable, an erroneous alarm sound may be generated. There is almost no need to do it anymore.

Note that in the embodiments described above, sensing was performed using an infrared sensor, but sensing may also be performed, for example, by applying ultrasonic waves to a moving body and detecting the presence or absence of reflection.

[Effects] According to the present invention, even when a large number of people move continuously, for example, it is almost impossible to make a false warning sound.
It is possible to obtain a moving object detection device that performs an appropriate alarm operation.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an electric circuit diagram showing details of the sensor circuit in FIG. 1,
Fig. 3 is a waveform diagram showing the signal obtained by the sensor circuit shown in Fig. 2, Figs. 4 and 5 are time charts and explanatory diagrams explaining the operation of Fig. 1, and Fig. 6 is a conventional It is an explanatory diagram for clarifying a problem. DT... Detection circuit SD... Sound alarm circuit CR... Sound alarm control circuit or higher

Claims (1)

[Claims] Detection that generates a first detection signal when a moving object is located in a first detection range, and generates a second detection signal when the moving object is located in a second detection range. a sound circuit that generates a first notification sound in response to the first detection signal and a second notification sound in response to the second detection signal; The alarm sound control circuit generates an activation prohibition signal in an updated manner every time a detection signal is generated, and prohibits activation of the first notification sound and the second notification sound while the activation prohibition signal is generated. Moving object detection device.