JPH10132928A - Method and device for detecting moving object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for detecting moving object so as to determine correctly existence of a moving object even under the condition where a background changes at very close intervals and perform properly updating of the background data. SOLUTION: The device comprises a transmitter 16 which sends a short-time ultrasonic signal intermittently, a receiver 18 which receives a reflected wave received every signal sending, a receiving circuit 20 which gets a received data in time sequence corresponding to its propagated time based on the received reflected wave, and a central calculating device 22. The central calculating device compares the received data delivered from the receiving circuit 20 with a threshold level predetermined according to the propagated time. When the received data is larger than the threshold level straight in a predetermined number of comparisons, the central calculating device determines that a moving object exists. Additionally, it calculates the difference of the this-time received data and the last-time received data from the receiving circuit 20. When the difference is found within acceptable change area straight in another predetermined number of calculations, it updates the threshold level, based on the latest received data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving object detecting method and a moving object detecting device using an ultrasonic wave, for example, for controlling an air conditioner or a lighting device, or a person entering a crime prevention and danger zone. The present invention relates to a moving object detecting method and a moving object detecting device used for security or the like for detecting a situation.

[0002]

2. Description of the Related Art Conventionally, when it is determined whether or not a moving object exists in a predetermined target area space, background data or a threshold value of the target area space is used to identify the moving object and the background. There is a need to. That is, in order to identify the presence or absence of a moving object using reflected waves of ultrasonic waves, it is necessary to discriminate the moving object such as a human against a background that does not move temporally.

As a method of this discrimination, a peak hold (maximum value) method, a sample hold method (averaging processing, standard deviation processing, temporal statistical processing) and the like are mentioned as conventional methods. In the peak hold method, the peak value (background data) of the received waveform of the reflected wave when there is no moving object is stored, and the peak value of the received waveform being measured exceeds the stored peak value. If there is something, it is discriminated that there is a moving object.

In the sample-and-hold method, a certain number of measurements are repeated to create an average reflected wave pattern (background data), which is used as a sample (reference value) pattern and has a standard deviation from the reflected wave at the time of measurement. When the value is exceeded, it is discriminated that the moving object exists. Conventionally, the following cases have been considered as triggers for a process of capturing these background data as new background data (this process is referred to as updating in the present specification). 2) How to perform a scheduled update (regular update) or periodic update using a timer, 3) How to manually force it, 4) How to automatically perform it under certain conditions, etc. is there.

In the method 1), since there is no background data before that (no memory), the reflected wave pattern from the target space immediately after the power is turned on is taken in as background data, and the background is kept as long as the power is kept on. Data-based method, 2)
The method of (3) is to capture the reflected wave pattern of the current target space as background data at regular intervals and rewrite the background data.The method (3) is not dependent on the time, but is instructed by the manual operation of the operator at that time. A method of capturing the reflected wave pattern as background data and rewriting the background data. As the method 4), various methods have been proposed. For example, as an example, an average of a plurality of reflected wave patterns up to M times before is used. And performing it as background data.

[0006]

However, for example, when the presence or absence of a person is to be determined in a room in the daytime where a worker frequently enters and leaves, that is, a file on a desk, an ashtray, Or, when a person is carried out in a space area where a foreign object other than a person changes the background irregularly, such as when a carry-on tool is newly installed in the target space or removed in reverse, the above 1) In the methods such as, 2) and 3), it cannot be said that appropriate background data is held at the time of measurement, and there is a problem that it is not possible to correctly determine the presence or absence of a moving object.

In the method 4), since the background data changes with time, it is possible to cope with a change in the background. However, this method is effective when the change in the background is slow. The background data is rewritten even when there is a large change in the background momentarily, so that the background data contains an error for a while after the change, and there is a problem that it is not possible to correctly determine the presence or absence of a moving object.

The present invention has been made in view of such a problem, and it is possible to correctly determine whether or not a moving object is present even in an environment where the background frequently changes, and to accurately extract background data. It is an object to provide a moving object detection method and a moving object detection device that can be updated.

[0009]

In order to achieve the above object, according to the first aspect of the present invention, a short-time ultrasonic signal is emitted to a predetermined target area space, and a reflected wave is emitted. Receiving, in the moving object detection method to determine whether a moving object is present or not in the predetermined target area space, intermittently emits the short-time ultrasonic signal, from a reflected wave received for each emission Compare the received data obtained in time series corresponding to the propagation time and the threshold level prepared in advance corresponding to the propagation time, and if the received data is larger continuously for a predetermined number of times, it is determined that the moving object exists. In addition to the determination, the reception data obtained in time series corresponding to the propagation time from the reflected wave received for each launch and the reception data obtained in time series corresponding to the propagation time from the previously received reflected wave Find difference from received data , If the difference between a second predetermined number of times consecutively is within allowed range of variation, and updates the threshold level based on the latest received data, characterized in that.

According to a second aspect of the present invention, a mobile unit exists in the predetermined target area space by emitting a short-time ultrasonic signal to a predetermined target area space and receiving a reflected wave thereof. In the moving object detection method to determine whether or not, the short-time ultrasonic signal is emitted intermittently, received data obtained in time series corresponding to the propagation time from the reflected wave received for each emission and its By comparing a threshold level prepared in advance corresponding to the propagation time and determining that the moving object is present when the received data is larger than the predetermined number of times continuously, the illuminance set in the predetermined target area space is determined. If the output from the meter is greater than the predetermined value, the received data obtained in time series corresponding to the propagation time from the reflected wave received for each launch and the propagation time corresponding to the reflected wave received last time Chronologically Determining a difference between the obtained received data,
The threshold level is updated based on the latest received data when the difference is within the allowable change width for the second predetermined number of consecutive times, and when the output from the illuminometer is equal to or less than the predetermined value, the latest reception is performed. Updating the threshold level based on data.

According to a third aspect of the present invention, a mobile unit exists in the predetermined target area space by emitting a short-time ultrasonic signal to a predetermined target area space and receiving its reflected wave. In the moving object detection method to determine whether or not, the short-time ultrasonic signal is emitted intermittently, received data obtained in time series corresponding to the propagation time from the reflected wave received for each emission and its Comparing with a threshold level prepared in advance corresponding to the propagation time, determining that the moving object is present when the received data is larger continuously for a predetermined number of times, and setting the microphone installed in the predetermined target area space If the output from is larger than the predetermined value, the received data obtained in time series corresponding to the propagation time from the reflected wave received for each launch, and the propagation time from the previously received reflected wave Time The difference from the received data obtained in a column is obtained, and if the difference is within the allowable change width for a second predetermined number of times, the threshold level is updated based on the latest received data, and the When the output is equal to or less than a predetermined value, the threshold level is updated based on the latest received data.

Further, according to a fourth aspect of the present invention, a mobile unit exists in the predetermined target area space by emitting a short-time ultrasonic signal to a predetermined target area space and receiving a reflected wave thereof. In the moving object detection method to determine whether or not, the short-time ultrasonic signal is emitted intermittently, received data obtained in time series corresponding to the propagation time from the reflected wave received for each emission and its By comparing with a threshold level prepared in advance corresponding to the propagation time, it is determined that the moving object is present when the received data is larger continuously for a predetermined number of times, and provided at the entrance to the predetermined target area space. If the key lock detection sensor of the door does not detect key lock, the reception data obtained in time series from the reflected wave received at each firing in accordance with the propagation time and the transmission data from the previously received reflected wave The difference from the received data obtained in time series corresponding to the time is obtained, and when the difference is within the allowable change width for the second predetermined number of times, the threshold level is set based on the latest received data. Updating, and when the key lock detection sensor detects a key lock, the threshold level is updated based on the latest received data.

[0013] The invention described in claim 5 is the first invention.
4. In any one of the moving object detection methods according to 4, the short-time ultrasonic signal is intermittently emitted a third predetermined number of times as an initial threshold level, and the propagation time is determined from a reflected wave received for each emission. It is characterized in that a threshold level is generated based on a maximum of received data obtained in time series.

According to a sixth aspect of the present invention, a mobile unit exists in the predetermined target region space by emitting a short-time ultrasonic signal to a predetermined target region space and receiving a reflected wave thereof. In a moving object detection device that determines whether or not to do, a transmitter that intermittently emits the short-time ultrasonic signal, a receiver that receives a reflected wave received for each emission, and a propagation from the obtained reflected wave A receiving circuit that obtains reception data in a time series according to time, a storage device that stores reception data obtained in a time series in response to a propagation time from a previously received reflected wave, and the reception circuit From the received data, and a threshold level prepared in advance corresponding to the propagation time, and when the received data is larger than the predetermined number of times continuously, it is determined that the moving object is present, and from the receiving circuit, Received data and Calculating a difference from the previous received data stored in the storage device and updating the threshold level based on the latest received data when the difference is within an allowable change width for a second predetermined number of consecutive times Equipment and
It is characterized by having.

According to a seventh aspect of the present invention, a mobile unit is present in a predetermined target area space by emitting a short-time ultrasonic signal to a predetermined target area space and receiving a reflected wave thereof. In a moving object detection device that determines whether or not to do, a transmitter that intermittently emits the short-time ultrasonic signal, a receiver that receives a reflected wave received for each emission, and a propagation from the obtained reflected wave A receiving circuit that obtains reception data in a time series corresponding to time, a storage device that stores reception data obtained in a time series corresponding to a propagation time from a reflected wave received last time, The illuminometer installed in the target area space, the received data from the receiving circuit, and a threshold level prepared in advance corresponding to the propagation time are compared, and when the received data is larger continuously for a predetermined number of times. It is determined that there is a moving object in When the output from the illuminometer is larger than a predetermined value, a difference between the reception data from the reception circuit and the previous reception data stored in the storage device is obtained, and the difference is obtained for a second predetermined number of times. When the difference is within the allowable change width, the threshold level is updated based on the latest received data, and when the output from the illuminometer is equal to or less than a predetermined value, the threshold level is updated based on the latest received data. And an arithmetic unit for updating.

In the invention according to claim 8, a short-time ultrasonic signal is emitted to a predetermined target area space, a reflected wave is received, and a moving object is present in the predetermined target area space. In a moving object detection device that determines whether or not to do, a transmitter that intermittently emits the short-time ultrasonic signal, a receiver that receives a reflected wave received for each emission, and a propagation from the obtained reflected wave A receiving circuit that obtains reception data in a time series corresponding to time, a storage device that stores reception data obtained in a time series corresponding to a propagation time from a reflected wave received last time, The microphone installed in the target area space, the received data from the receiving circuit, and a threshold level prepared in advance corresponding to the propagation time are compared, and when the received data is larger continuously for a predetermined number of times, There is a moving object When the output from the microphone is larger than the predetermined value, the difference between the reception data from the reception circuit and the previous reception data stored in the storage device is obtained, and the difference is obtained for the second predetermined number of times. When the difference is within the allowable change width, the threshold level is updated based on the latest received data, and when the output from the microphone is equal to or less than a predetermined value, the threshold level is updated based on the latest received data. And an arithmetic unit for updating.

According to a ninth aspect of the present invention, a mobile unit is present in the predetermined target area space by emitting a short-time ultrasonic signal to a predetermined target area space and receiving its reflected wave. In a moving object detection device that determines whether or not to do, a transmitter that intermittently emits the short-time ultrasonic signal, a receiver that receives a reflected wave received for each emission, and a propagation from the obtained reflected wave A receiving circuit that obtains reception data in a time series corresponding to time, a storage device that stores reception data obtained in a time series corresponding to a propagation time from a reflected wave received last time, A key lock detection sensor for a door provided at the entrance to the target area space, data received from the reception circuit, and a threshold level prepared in advance corresponding to the propagation time are compared, and reception is performed a predetermined number of times continuously. Data is larger In the case where it is determined that the moving object is present and the key lock detection sensor does not detect the key lock, the difference between the received data from the receiving circuit and the previous received data stored in the storage device is obtained, The threshold level is updated based on the latest received data when the difference is within the allowable change width for a second predetermined number of consecutive times, and when the key lock detection sensor detects a key lock, the latest reception is performed. An arithmetic unit for updating the threshold level based on data.

The invention according to claim 10 is the invention according to claim 6.
In any one of Items 9 to 9, the arithmetic unit emits the short-time ultrasonic signal intermittently a third predetermined number of times as an initial threshold level, and corresponds to a propagation time from a reflected wave received for each emission. It is characterized in that a threshold level is generated based on a maximum of received data obtained in time series.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a moving object detecting device for realizing a moving object detecting method of the present invention. A moving object detecting device 10 receives a transmission trigger and performs amplified transmission in a burst format. A transmitting circuit 14 that outputs an electric signal, a transmitter 16 that converts a transmitted electric signal into an ultrasonic wave, a receiver 18 that receives an ultrasonic wave and converts it to a received electric signal, and receives the received electric signal. A receiving circuit 20 that obtains received data in a time series corresponding to a propagation time from the obtained reflected wave, and controls transmission timing, receives an output of the receiving circuit 20, and sends a reset signal to the receiving circuit 20, Further, a central processing unit 22 for determining the presence or absence of a moving object, updating background data, and the like, and a storage device 24 for storing received data, background data, and the like are provided.

The receiving circuit 20 amplifies an electric signal received from the receiver 18, receives a signal from the receiving amplifier 26, performs sampling and detection, and performs sampling and detection.
And a A / D converter 32 for performing A / D conversion of a signal from the sample and hold circuit 28.

As shown in FIG. 2, when the transmission circuit 14 receives a transmission trigger (FIG. 2A) of a fixed period (for example, once every second) sent from the central processing unit 22, the transmission circuit 1
From 4, a burst-type amplified transmission electric signal (FIG. 2B) is output, converted into an ultrasonic wave by the transmitter 16, and the ultrasonic wave is emitted to a predetermined target region space. The ultrasonic wave reflected on the target existing in the predetermined target region space is received by the receiver 18, and the reception electric signal (FIG. 2C) amplified by the reception amplifier 26 is output and transmitted to the sample and hold circuit 28. Is done. The sample and hold circuit 28 operates in a sample state and a hold state, and switches between these states according to the output from the comparator 30. That is, the current input signal from the receiving amplifier 26 and the sample and hold circuit 28
And if the input of the receiving amplifier 26 is larger, the sample and hold circuit 28 is set to the sample state, the input value at that time is set as a new hold value, and the input of the receiving amplifier 26 is When the value is smaller, the sample hold circuit 28 is set in the hold state, and the hold value at that time is held. By this operation, the maximum value of the input signal is held (FIG. 2D). On the other hand, a reset signal is output from the central processing unit 22 every predetermined period (for example, 500 μs) (FIG. 2E), and the output value of the sample-and-hold circuit 28 is cleared to zero volt and before the reset. Hold value is A / D
The signal is sent to the converter 32, A / D converted by the A / D converter 32 (FIG. 2F), and taken into the central processing unit 22. In this manner, N pieces of maximum value data for each fixed period are fetched.

As described above, the operation of transmitting one transmission trigger signal and subsequently taking in N data of the received wave is called "measurement", and the N data strings obtained by the measurement are referred to as "measurement". This is called an echo pattern. Central processing unit 22
Is constituted by a microcomputer or the like, and executes the flowchart of FIG. 3 according to a program stored in advance in a ROM or the like.

First, at the same time as turning on the power or by resetting, the program starts (S1), and the learning mode is executed (S2). The learning mode is for creating an initial background pattern. After the measurement is performed based on the above procedure, a transmission trigger is transmitted, N pieces of received data are captured, and an echo pattern is created (S2, S3). , An echo pattern composed of N data stored in advance in the storage device 24 is read, and the corresponding data is compared with the echo pattern obtained by the current measurement. If the current received data is larger, Then, the data stored in the storage device 24 is updated with the received data, and if the data stored in the storage device 24 is larger, the data in the storage device 24 is not updated and remains as it is (S5). ).
In the case of the first measurement, the data stored in the storage device 24 is set to 0 in advance, and the echo pattern obtained by the first measurement is stored in the storage device 24 as it is.

Next, it is determined whether or not the measurement has been performed M times (for example, 30 times) (S6).
S3 to S6 are repeated. In the learning mode, a background pattern is determined by performing M measurements. The number of times M may be appropriately selected in consideration of the fluctuation of the air flow and the fluctuation of the echo pattern due to the moving machine. In this way, the measurement is performed M times, and if the determination in step S6 is YES, the process shifts to the automatic learning mode in FIG. 4 (S8). At this time, the maximum value of the N data is stored in the storage device 24 among the M measurements, and a set of these N maximum values becomes the background pattern (FIG. 6A). reference).

In the automatic learning mode, the measurement is performed in the same manner, and the background pattern is automatically rewritten, that is, updated, by paying attention to the change of the measured data every time. For example, if a person enters the target area space and places an object on a desk which is a background in the object area space, the echo pattern changes, so that it is determined that the person is still present even after the person leaves. In this case, an incorrect judgment is made. In this auto-learning mode, when there is a person or moving object, the person or moving object usually does not freeze for a long time,
Think there is some movement. On the other hand, it is assumed that an object is usually stationary unless it moves. On this premise, it is checked whether or not a change (difference) between each data corresponding to each propagation time of the echo pattern of the previous measurement and the echo pattern of the current measurement is within a certain value (allowable change width) (FIG. 6).
(B)).

When the difference is within the allowable change range for a while, it is determined that a person is absent, and the echo pattern at that time is rewritten as a background pattern. The permissible change width at this time is determined in consideration of the fluctuation of the echo due to the airflow. Specifically, the measurement is performed in steps 9 and 10, and the previous echo pattern stored in the storage device 24 and the current echo pattern are compared (S11). It is determined whether or not the current echo pattern is in a range between a product obtained by adding a certain value to the previous echo pattern and a product obtained by subtracting a certain value from the previous echo pattern, and whether the state has continued for L times ( S12) If yes, step S
13, the background pattern is rewritten to the current echo pattern, and if no, the process proceeds to step 14, where the background pattern already stored in the storage device 24 is read out.
The process proceeds to the person determination mode in FIG. 5 (S15).

In the person determination mode, when any of the N data of the measured echo pattern exceeds a threshold level obtained by calculating (adding) a margin in consideration of a drift or the like to the background pattern, it is determined that a person exists. (See FIGS. 6 (c), (d-1) and (d-2)). Specifically, the measured echo pattern obtained by measuring in Steps 9 and 10 is compared with the background pattern obtained in Step 13 or 14 (S16), and whether or not the measured echo pattern has exceeded the threshold level is determined. In addition, it is determined whether or not the state has been exceeded K times (S17). If yes, it is determined that a person exists (S18). If no, it is determined that no person exists (S19). After that, the automatic learning mode and the person determination mode are repeated again. Here, FIG.
As shown in (c), the threshold level is generated from a value obtained by adding a margin in consideration of the drift and the like to the background pattern. This margin may be the same for all N data as shown in the figure. Considering the property that the amplitude fluctuation of the reflected wave increases as the propagation time becomes longer (that is, a distant object), a weight may be added so that the margin is not constant and the data becomes longer as the propagation time becomes longer. Also, as shown in FIG. 6 (d-1),
When all of the N data of the measured echo pattern are below the threshold level, it is determined that a person is absent, and FIG.
As shown in (d-2), if any of the N pieces of data of the measurement echo pattern is larger than the threshold level, it is determined that the state has exceeded the threshold level and whether this state is continued for K times. Is determined.

By performing the processing described above, the presence or absence of a person can be determined, and the background data can be accurately rewritten. The predetermined number of consecutive times L and K may be one, but may be set to an appropriate number in consideration of data fluctuation. Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, in addition to the configuration of FIG. 1, an illuminometer 31 is provided in a predetermined target area space, and a comparator 34 that compares a voltage generated from the illuminometer 31 with a reference voltage 32 is provided. When the voltage is equal to or lower than the reference voltage, a high level signal is sent to the central processing unit 22. That is, a value lower than the reference voltage is set to a value suitable for identifying a state where the night light is not turned on, and the central processing unit 22 is notified that the night light is not turned on. If the night light is not on, it is appropriate to judge that there is no person, so the background data is updated based on this.

The processing performed by the central processing unit 22 based on this configuration will be described mainly with reference to FIG. 8 while referring to differences from the first embodiment (shown in the flowcharts of FIGS. 3 and 5). The processing is executed in common in this embodiment as well.) In the automatic learning mode of the present embodiment, after the measurement is performed in steps 9 and 10, the signal from the comparator 34 is fetched (S20), It is determined whether or not the signal from is high (S21). If yes, it is determined that the light is not on at night and step 1
Proceeding to 3, the background data is rewritten with the echo pattern obtained this time. In the case of No, it is determined that the light is on or it is during the day, and the same processing of steps 11 to 14 as in the first embodiment is performed.

As described above, when the light is not turned on at night, the background data is constantly updated. Further, a third embodiment of the present invention will be described with reference to FIG. In this embodiment, in the configuration of FIG. 8, a microphone 36 is installed in a predetermined target area space instead of the illuminometer 31, and a voltage generated from the microphone 36 is compared with a comparator 34 that compares a reference voltage 33. And sends a signal to the central processing unit 22 when the voltage is equal to or lower than the reference voltage. That is, a value lower than the reference voltage is set to a value suitable for identifying a quiet state at night, and the central processing unit 22 is notified of quietness at night. Since it is appropriate to judge that there is no person when it is quiet at night, the background data is updated based on this.

Also in the third embodiment, the same processing as that of FIG. 8 is performed in the automatic learning mode, so that the background data is always updated when it is quiet at night. Further, a fourth embodiment of the present invention will be described with reference to FIG.
In this embodiment, a key lock detection sensor 38 for a door is provided at the entrance to a predetermined target area space instead of the illuminometer 31 in the configuration of FIG.
Sends the signal to the central processing unit 22. That is, when the door is locked, it is appropriate to determine that no person is present in the office or the like, and the background data is updated based on this.

Also in the fourth embodiment, the same processing as in FIG. 8 is performed for the automatic learning mode, so that the background data is updated whenever the door is locked. However, it is assumed that the output from the comparator 34 in Steps 20 and 21 in FIG. 8 is replaced with the output from the key lock detection sensor 38. The result of the determination of the presence / absence of a person in the predetermined target area space according to the above embodiment can be used for, for example, a blowing system in air conditioning control. In a ventilation system for air-conditioning control, it may be uneconomical to blow all air-conditioned air from an air conditioner to all rooms or all areas (areas) of a space. In such a case, it is desired to perform so-called spot air-conditioning, in which air is blown only to an area where a person is present, and the presence / absence of a person in the area is determined by the above-described method. Judgment can be made using the embodiment, and blowing or stopping of blowing can be determined according to the result.

Now, it is assumed that the air-conditioned air is supplied from one air conditioner to a plurality of rooms or a plurality of spaces from the outlet through a duct. As shown in FIG. 11, an area in which the blowing unit 50 having one set of four blowing ports can blow air is called a service area 52,
When the blowing area covered by each outlet 50a is referred to as a sub-zone (I, II, III, IV) of every 4 m square, the transmitter 16 and the receiver 16 each having the sub-zone as a target area space are provided near each outlet 50a. An ultrasonic sensor 19 comprising a vessel 18 is arranged.

The signal from the ultrasonic sensor 19 is sent to the central processing unit 22 via the receiving circuit 20, and the presence or absence of a person is determined by the above-described method. The sub-zone which is sent to each outlet 50a and is determined to have a person is blown, and the sub-zone determined to be absent is blown by a blow control valve (damper) incorporated in each outlet 50a. Stop the ventilation.

Further, by installing a plurality of such blow-off units, an economical air-conditioning service can be provided even in a wide space area. In addition, monitoring and inspection departments where people are present only for a limited time in factories, air-conditioning in areas where people are not always present, such as shipping and receiving departments where all air conditioning is uneconomical, conference rooms, reception rooms, etc. It is also effective in control.

The present invention can be applied to lighting control and crime prevention in addition to air conditioning control.

[0037]

As described above, according to the first and sixth aspects of the present invention, the moving body does not stay stationary for a long time, while a new object other than the moving body is added. Or if the background changes after being removed, it will not move after some time,
The reception data obtained in time series corresponding to the propagation time from the reflected wave received for each launch and the reception data obtained in time series corresponding to the propagation time from the previously received reflected wave The difference is obtained, and if the difference is within the allowable change range for the second predetermined number of times in succession, the threshold level is updated based on the latest received data, so that the threshold level (or Background data) can be changed. Therefore, it is possible to detect a moving object even if there is a frequent background change, and it is possible to update a correct threshold level (or background data) even if there is a large background change. Since the threshold level (or background data) is automatically updated, no human intervention is required.

According to the second and seventh aspects of the present invention, in addition to having the same effects as the first and sixth aspects, when the output from the illuminometer is equal to or less than a predetermined value, By updating the threshold level based on the latest received data when the target area space is dark and it is considered that there is a very low possibility that a moving object, especially a person, is present,
Accurate data can be secured as a background.

According to the third and eighth aspects of the present invention, in addition to having the same effects as those of the first and sixth aspects, when the output from the microphone is equal to or less than a predetermined value, Update the threshold level based on the latest received data to ensure accurate data as background when the area space is quiet and it is very unlikely that there are moving objects, especially people. Can be.

According to the fourth and ninth aspects of the invention, in addition to having the same effects as the first and sixth aspects, when the key lock detection sensor detects a key lock, that is, when a predetermined key lock is detected, When the target area space is locked and it is thought that the possibility of the presence of a moving object, especially a person, is extremely low, updating the threshold level based on the latest received data enables accurate data as background. Can be secured.

According to the fifth and tenth aspects of the present invention, the short-time ultrasonic signal is intermittently emitted a third predetermined number of times as an initial threshold level, and the reflected wave received at each emission is emitted. By generating the threshold level based on the largest one of the received data obtained in time series corresponding to the propagation time from, the initial threshold level that is less likely to be erroneously detected can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a signal waveform diagram of (a) to (f) in FIG.

FIG. 3 is a part of a flowchart showing processing in the central processing unit of FIG. 1;

FIG. 4 is a part of a flowchart showing a process in the central processing unit in FIG. 1;

FIG. 5 is a part of a flowchart showing processing in the central processing unit in FIG. 1;

6A is an explanatory diagram of creation of initial background data, FIG. 6B is an explanatory diagram of a previous echo pattern and an allowable change width, FIG. 6C is an explanatory diagram of background data and a threshold level, and FIG. (d-1) is an explanatory diagram showing a state where the measured echo pattern does not exceed the threshold level, and (d-2) is an explanatory diagram showing a state where the measured echo pattern has exceeded the threshold level.

FIG. 7 is a block diagram showing a second embodiment of the present invention.

FIG. 8 is a flowchart diagram in place of FIG. 4 in the second embodiment.

FIG. 9 is a block diagram showing a third embodiment of the present invention.

FIG. 10 is a block diagram showing a fourth embodiment of the present invention.

FIG. 11 is an explanatory diagram in a case where the present invention is applied to a blowing system in air conditioning control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Moving body detection device 16 Transmitter 18 Receiver 20 Receiving circuit 24 Storage device 22 Central processing unit (Calculation unit) 31 Illuminometer 36 Microphone 38 Key lock detection sensor

Continuation of the front page (72) Inventor Takashi Kamiya 2-16-46 Minami Kamata, Ota-ku, Tokyo Inside Tokimec Co., Ltd. (72) Inventor Hiroshi Kashise 2-16-46 Minami-Kamata, Ota-ku Tokyo (72) Inventor Ryohei Mogi 2-16-46 Minami Kamata, Ota-ku, Tokyo Inside Tokimec Co., Ltd.

Claims (10)

[Claims] 1. A moving body that emits a short-time ultrasonic signal to a predetermined target area space, receives a reflected wave thereof, and determines whether or not the moving body exists in the predetermined target area space. In the detection method, the short-time ultrasonic signal is intermittently emitted, and reception data obtained in a time series corresponding to a propagation time from a reflected wave received for each emission and prepared in advance corresponding to the propagation time are prepared in advance. The received threshold value is compared with the threshold level, and if the received data is larger than the predetermined number of times, it is determined that the moving object is present.In addition, the reflected wave received for each emission is obtained in time series from the reflected wave corresponding to the propagation time. The difference between the received data obtained and the received data obtained in time series corresponding to the propagation time from the reflected wave received last time is determined, and the difference is within the allowable change width for the second predetermined number of consecutive times. The latest received data Moving body detecting method wherein updating the threshold level, it is characterized on the basis of. 2. A moving body that emits a short-time ultrasonic signal to a predetermined target area space, receives a reflected wave thereof, and determines whether a moving body exists in the predetermined target area space. In the detection method, the short-time ultrasonic signal is intermittently emitted, and reception data obtained in a time series corresponding to a propagation time from a reflected wave received for each emission and prepared in advance corresponding to the propagation time are prepared in advance. The threshold level is compared with the threshold value, and when the received data is larger than the predetermined number of times, it is determined that the moving object is present, and the output from the illuminometer installed in the predetermined target area space is larger than a predetermined value. If large, the received data obtained in time series corresponding to the propagation time from the reflected wave received for each launch, and the received data obtained in time series corresponding to the propagation time from the previously received reflected wave Difference from received data The threshold level is updated based on the latest received data when the difference is within the allowable change width for the second predetermined number of times consecutively, and when the output from the illuminometer is equal to or less than the predetermined value, the threshold level is updated. And updating the threshold level on the basis of the received data. 3. A moving object that emits a short-time ultrasonic signal to a predetermined target region space, receives a reflected wave thereof, and determines whether or not the moving object exists in the predetermined target region space. In the detection method, the short-time ultrasonic signal is intermittently emitted, and reception data obtained in a time series corresponding to a propagation time from a reflected wave received for each emission and prepared in advance corresponding to the propagation time are prepared in advance. The threshold level is compared with the threshold level, and when the received data is larger than the predetermined number of times continuously, it is determined that the moving object is present, and the output from the microphone installed in the predetermined target area space is larger than a predetermined value. In this case, the reception data obtained in time series corresponding to the propagation time from the reflected wave received for each launch and the reception data obtained in time series corresponding to the propagation time from the previously received reflected wave data The threshold level is updated based on the latest received data when the difference is within the allowable variation range for the second predetermined number of consecutive times, and when the output from the microphone is equal to or less than the predetermined value, And updating the threshold level based on the latest received data. 4. A moving body that emits a short-time ultrasonic signal to a predetermined target area space, receives a reflected wave thereof, and determines whether or not the moving body exists in the predetermined target area space. In the detection method, the short-time ultrasonic signal is intermittently emitted, and reception data obtained in a time series corresponding to a propagation time from a reflected wave received for each emission and prepared in advance corresponding to the propagation time are prepared in advance. The received threshold value is compared with the threshold level, and when the received data is larger than the predetermined number of times continuously, it is determined that the moving object is present. When the key lock is not detected, the reception data obtained in time series corresponding to the propagation time from the reflected wave received for each launch, and the time series corresponding to the propagation time from the previously received reflected wave. To The threshold level is updated based on the latest received data, and when the difference is within the permissible range of change for a second predetermined number of times, the key lock detection sensor detects the key lock. And detecting the threshold level based on the latest received data. 5. The moving object detection method according to claim 1, wherein the short-time ultrasonic signal is emitted intermittently a third predetermined number of times as an initial threshold level, and a reflection received at each emission. A moving object detection method, comprising: generating a threshold level based on a maximum of received data obtained in time series from a wave in accordance with a propagation time. 6. A moving object that emits an ultrasonic signal for a short time to a predetermined target region space, receives a reflected wave thereof, and determines whether or not the moving object exists in the predetermined target region space. In the detection device, a transmitter that intermittently emits the short-time ultrasonic signal; a receiver that receives a reflected wave received for each emission; and a time-series corresponding to the propagation time from the obtained reflected wave. A receiving circuit for obtaining received data, a storage device for storing received data obtained in a time series corresponding to a propagation time from a reflected wave received last time, a received data from the receiving circuit, and the propagation thereof. By comparing with a threshold level prepared in advance corresponding to the time, when it is determined that the moving object is present when the received data is larger than the predetermined number of times continuously, the received data from the receiving circuit and the received data are stored in the storage device. Remembered Calculating a difference from the previous received data, and updating the threshold level based on the latest received data when the difference is within an allowable change width for a second predetermined number of consecutive times. Characteristic moving object detection device. 7. A moving body that emits a short-time ultrasonic signal to a predetermined target area space, receives a reflected wave thereof, and determines whether or not the moving body exists in the predetermined target area space. In the detection device, a transmitter that intermittently emits the short-time ultrasonic signal; a receiver that receives a reflected wave received for each emission; and a time-series corresponding to the propagation time from the obtained reflected wave. A receiving circuit that obtains received data, a storage device that stores received data obtained in time series corresponding to a propagation time from a reflected wave received last time, and a storage device that is installed in the predetermined target region space. An illuminometer, comparing the reception data from the reception circuit with a threshold level prepared in advance corresponding to the propagation time, and if the reception data is continuously larger than a predetermined number of times, it is determined that the moving object exists. With the illuminometer If these outputs are greater than a predetermined value, the difference between the received data from the receiving circuit and the previous received data stored in the storage device is determined, and the difference is allowed for the second predetermined number of consecutive times. An arithmetic unit that updates the threshold level based on the latest received data when the value is within the predetermined range, and updates the threshold level based on the latest received data when the output from the illuminometer is equal to or less than a predetermined value. A moving object detection device, comprising: 8. A moving object that emits a short-time ultrasonic signal to a predetermined target region space, receives a reflected wave thereof, and determines whether a moving object exists in the predetermined target region space. In the detection device, a transmitter that intermittently emits the short-time ultrasonic signal; a receiver that receives a reflected wave received for each emission; and a time-series corresponding to the propagation time from the obtained reflected wave. A receiving circuit that obtains received data, a storage device that stores received data obtained in time series corresponding to a propagation time from a reflected wave received last time, and a storage device that is installed in the predetermined target region space. Microphones, data received from the receiving circuit, and a threshold level prepared in advance corresponding to the propagation time are compared, and when the received data is larger continuously for a predetermined number of times, it is determined that the moving object is present. , Ma If the output from the microphone is larger than a predetermined value, a difference between the received data from the receiving circuit and the previous received data stored in the storage device is obtained, and the difference is allowed to change for a second consecutive number of times. An arithmetic unit that updates the threshold level based on the latest received data when the distance is within the width, and updates the threshold level based on the latest received data when the output from the microphone is equal to or less than a predetermined value. A moving object detection device, comprising: 9. A moving body that emits a short-time ultrasonic signal to a predetermined target area space, receives a reflected wave thereof, and determines whether a moving body exists in the predetermined target area space. In the detection device, a transmitter that intermittently emits the short-time ultrasonic signal; a receiver that receives a reflected wave received for each emission; and a time-series corresponding to the propagation time from the obtained reflected wave. A receiving circuit that obtains received data, a storage device that stores received data obtained in a time series corresponding to a propagation time from a reflected wave received last time, and provided at an entrance to the predetermined target area space. The key lock detection sensor of the door and the reception data from the reception circuit are compared with a threshold level prepared in advance in accordance with the propagation time, and when the reception data is continuously larger than a predetermined number of times, the movement is performed. Body exists When the key lock detection sensor does not detect the key lock, the difference between the reception data from the reception circuit and the previous reception data stored in the storage device is obtained, and the difference is determined for the second predetermined number of times. If the difference is within the allowable change range, the threshold level is updated based on the latest received data.If the key lock detection sensor detects key lock, the threshold is updated based on the latest received data. A moving object detection device, comprising: a calculation device that updates a level. 10. The computing device according to claim 1, wherein the short-time ultrasonic signal is intermittently set to a third threshold level as an initial threshold level.
Launched a predetermined number of times, of the received data obtained in chronological order corresponding to the propagation time from the reflected wave received for each launch, generate a threshold level based on the largest one,
The moving object detection device according to any one of claims 6 to 9, wherein: