JP2001311191A - Moving body detection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent erroneous detection of flushing water and a human body in the case that a Doppler sensor making use of radio waves as the moving body detection means for an automatic faucet of a washstand is used. SOLUTION: A system is a delivery water controller regulating the opening/ closing of a faucet installed in a washstand and provided with a means transmitting radio waves for detection of a human body, a means receiving reflected waves of the radio waves transmitted by the transmitting means, and a moving body detection sensor obtaining the difference between the frequency of the signal received by the receiving means and the frequency of the signal transmitted by the transmitting means and generating the differential signal according to the difference. In this system, the opening/closing of the faucet is controlled on the basis of the wave form pattern of the differential signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving body detection system for an automatic faucet installed on a wash basin.

[0002]

2. Description of the Related Art Conventionally, a method of detecting a moving object by a device for controlling water discharge of a faucet installed in a wash basin generally uses a photoelectric infrared sensor, and this sensor is inexpensive. Therefore, it is widely used. However, since infrared rays use the reflection of light, a window that transmits light is necessary.If the window becomes dirty, the detection accuracy will be degraded and the sensor will be installed in a position where there is no obstacle to the light. Was limited. In addition, since it is necessary to condense light and travel straight, there is a problem that it is difficult to detect a wide area. On the other hand, as another means for detecting a human body, a Doppler sensor using radio waves can be considered. Since this Doppler sensor has the property of penetrating resin and ceramics, it can be concealed in the body cover, and it can detect the state of a person, that is, whether it is approaching or moving away, and where it is located. it can. The Doppler sensor includes means for transmitting, means for receiving the reflected wave of the radio wave transmitted by the transmitting means, and a difference between the frequency of the signal received by the receiving means and the frequency of the signal transmitted by the transmitting means. And a means for generating a signal corresponding to the difference. It is known that among sensors using radio waves, it is generally effective to use electromagnetic waves having a frequency band of 1 GHz to 100 GHz for human body detection.
The principle of human body (motion) detection using the Doppler effect by radio waves (especially micro and millimeter waves) is as follows. Basic _{formula: ΔF S -F b = 2 ×} F S × ν / c ΔF: Doppler frequency F _S: transmission frequency F _b: reflection frequency [nu: walking speed of a human c: speed of light ^{(300 × 10 6 m / s} ) Antenna F _S transmitted from the is reflected in the body towards the hot water washing toilet becomes subjected to Doppler frequency shift due to the relative motion [nu F _b. At this time, the frequency difference ΔF between the transmitted wave and the reflected wave can be extracted as a detection signal. At this time, since the distance between the antenna and the human body is inversely proportional to the amplitude of ΔF, if the value of ΔF can be detected, the position of the person can be detected. Further, by analyzing the frequency spectrum of ΔF, it is possible to detect whether a person is approaching or moving away, and thus it is possible to detect the position and the moving direction of the human body.

[0003]

However, when this Doppler sensor is used for detecting the moving body of an automatic faucet of a wash basin, the washing water is detected and it is as if a human hand is moving within the ball surface. Could have been done.
In the case of a photoelectric infrared sensor, reflected light from the ball surface may be detected in some cases, and it is necessary to adjust the amount of light. The present invention has been made to solve such a problem, and prevents erroneous detection of washing water and a person when a Doppler sensor using radio waves is used for a moving body detecting means of an automatic faucet of a wash basin. It is intended to provide a means for doing so.

[0004]

Means for Solving the Problems and Action / Effect The invention according to the first aspect of the present invention has been made to solve the above-mentioned problems, and is a water discharge control device for controlling opening and closing of a water faucet installed on a wash basin. , Means for transmitting radio waves for human body detection,
Means for receiving a reflected wave of a radio wave transmitted by the transmitting means, and a difference signal obtained by calculating a difference between the frequency of the signal received by the receiving means and the frequency of the signal transmitted by the transmitting means. In the moving object detection system provided with the moving object detection sensor that generates the water, the opening and closing of the faucet is controlled by the waveform pattern of the difference signal.
In the Doppler sensor using radio waves, a characteristic of an output waveform pattern of a difference signal thereof appears depending on a human behavior pattern. For example, when a person approaches a toilet, the amplitude gradually increases at a certain frequency. When the user stops in front of the toilet, the waveform suddenly disappears, and the waveform becomes a low-frequency waveform. Further, the transmittance and the absorptivity differ depending on the object to be measured. The microwave absorptance increases (is easily absorbed) as the relative permittivity of the substance increases. Transmittance tends to be opposite to reflectivity. Incidentally, the relative dielectric constant of the substance is as follows, although it differs slightly depending on the frequency, the ambient temperature, and the like. Water: 80, pottery: 4-6, person: (moisture: about 55%, fat: about 25%, solids: 15.
%, Inorganic mass. That is, water absorbs microwaves, and pottery is easily reflected. In the present invention, it is possible to determine whether or not water is flowing out of the automatic faucet by using the above-mentioned properties of the Doppler sensor and the physical properties of the substance to be detected, and it is also possible to determine whether a person is moving his or her hand.

[0005] The invention according to claim 2 is characterized in that the opening and closing control of the automatic faucet of the wash basin is performed based on the rate of change of the amplitude of the difference signal. The amplitude of the difference signal of the Doppler sensor changes according to the distance from the Doppler sensor to a person. Therefore, by grasping the rate of change of the amplitude, it is possible to predict the movement state of the position of the person (here, mainly the hand). In the present invention, by learning the behavior pattern of a person by the change rate of the amplitude of the difference signal of the Doppler sensor, it is determined whether the difference signal of the Doppler sensor is for reflection by washing water or movement of a human hand. It is possible to judge and accurately wash human hands. In addition, the change in amplitude depends on the ball surface of the wash basin, washing water,
This can also be a source of judgment, as it depends on the human hand.

[0006] The invention according to claim 3 is characterized in that the opening and closing control of the automatic faucet of the sink is performed based on the rate of change of the frequency of the difference signal. The frequency of the difference signal of the Doppler sensor changes according to the speed at which a person moves. Therefore, by grasping the rate of change of the frequency, it is possible to predict the state of change in the moving speed of a person (here, mainly a hand). In the present invention, by learning the behavior pattern of a person (here, mainly a hand) based on the rate of change of the frequency of the Doppler sensor difference signal, whether the Doppler sensor difference signal is due to reflection by water, Alternatively, it can be determined whether the movement is a human hand, and the human hand can be accurately washed.

According to a fourth aspect of the present invention, in the water discharge control device for controlling opening and closing of a water faucet installed in a washstand, a sensor detection area is provided on the upper arm from the wrist when washing the palm. And In the present invention, since the detection area of the moving object detection sensor is provided at a position where water is unlikely to hit, the flow of water and the movement of a human hand are not erroneously recognized. That is, since only data relating to the movement of the human hand can be collected, the load on the signal processing device provided in the faucet can be reduced.

According to a fifth aspect of the present invention, a transmitting means is provided in a faucet provided on a wash basin, and a receiving means is provided at a portion opposed to the transmitting means, and attenuation of the transmission wave in the receiving means. The opening and closing control of the faucet is performed by measuring the rate. In the present invention, since the faucet has a radio wave transmitting unit and a radio wave receiving unit at the opposing portion, disturbance elements are reduced and the measurement accuracy is improved as compared with the case of measuring the reflected wave of the radio wave. For example, the transmitted wave is radiated toward the part where people wash their hands and is highly straight forward, so from the radio wave transmission part in the faucet, from the ball surface of the wash basin located farther from the hand (that is, pottery) Has a fairly strong reflection. In terms of distance, it may be difficult to discriminate between the intensity of the radio wave reflected from the hand of the person being washed closer to the ball surface and the strength of the reflection from the ball surface located far away. However, in this case, there is no need to consider the influence of the ball surface at all, since the receiving portion is located opposite to the portion of the faucet where the water comes out.

The invention according to claim 6 is characterized in that a plurality of the receiving means are provided, and the faucet opening / closing control is performed by measuring an attenuation state of each received wave received by the receiving means. And Depending on the user, the position of the hand to be washed may vary, and depending on the type of faucet, the position of the spout may not be constant. In this case, when looking at the movement of a human hand by looking at the transmission of radio waves, the false detection rate may be increased. In the present invention, since a plurality of receiving units are provided,
Stable detection can be performed irrespective of the user's habit, the type of faucet, and the shape of the sink. Further, since the state (flow rate, direction, etc.) of the washing water can also be determined, it is possible to realize various opening / closing control of the faucet.

[0010]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[0011]

[Embodiment 1] FIG. 1 shows an example in which a moving object detection sensor is incorporated in a moving object detecting device of an automatic faucet of a wash basin, and an example in which a sensor position is provided at a tip portion of the faucet. FIG. 2 is a configuration diagram of the moving body detection human body detection sensor. First, the configuration will be described. The inside of the moving object detection sensor unit 3 has the configuration shown in FIG. 2. First, an instruction signal to the transmission circuit of the microcomputer 5 for controlling the entire apparatus is transferred through the signal line 6, and the transmission circuit receives the signal. Functions, and a signal for moving object detection is transmitted via the transmission antenna 7. The transmitted radio wave collides with an object, is reflected, and is taken into the receiving circuit via the receiving antenna 8. At this time, the frequency of the radio wave reflected from the moving object is changed by the Doppler effect compared to the transmitted radio wave. At this time, the moving speed can be converted by the frequency, and the position can be converted by the amplitude.

Next, the operation will be described. The automatic faucet 2 discharges washing water toward the ball surface 1 of the sink. The trigger for starting the water discharge is when the moving body detection sensor unit 3 detects the human hand 4. Further, the water discharge is stopped when the microcomputer 5 receiving the signal from the moving body detection sensor unit 3 determines that the human hand 4 has changed from the detection state to the detection state. Furthermore, the moving body detection sensor unit 3 also considers the directivity of the transmission radio wave from the moving body detection sensor unit 3 and considers the position where the transmission radio wave does not hit the washing water (for structural reasons, when washing the palm or back of the hand, the wrist is used). The upper arm is not exposed to water.)
It is useful for detecting accurately.

[0013]

[Embodiment 2] FIG. 3 shows a waveform of a Doppler signal of the moving body detection sensor, in which washing water is detected. FIG.
It is the waveform of the Doppler signal of this moving body detection sensor, and is an example of detecting a human hand. The area 4-1 in FIG. 4 is a state where the hand is slowly moved at a position far from the water discharge port, and the area 4-2 in FIG. 4 is a state where the hand is washed without being busy nearby. Further, a region 4-3 in FIG. 4 shows a state in which cleaning is being performed gently near the water discharge port. FIG. 5 is an example in which a moving object detection sensor is incorporated in the moving object detection device of the automatic faucet of the washstand, and the position of the sensor is not particularly limited.

Next, the operation will be described. When a person wash his / her hands with the automatic faucet installed on the wash basin, a waveform as shown in FIG. 4 is detected. Normally, there is no human hand 4 and no washing water, so that a difference signal of the Doppler sensor is not generated. When a person tries to wash his hands from this state, the above-mentioned difference signal is generated. It is enough to start water discharge with this.
When an object suddenly drops, a signal is generated. However, in this case, a signal is generated only momentarily, and the amplitude itself is small. However, in the case of the human hand 4, a waveform having an amplitude clearly different from that of an irregular or unexpected falling object appears as shown in FIG. That is, erroneous water discharge can be prevented by setting the change rate of the amplitude in advance.

After that, when the washing is completed and the hand is moved away from the ball surface 1, the washing water still flows. FIG. 3 shows the waveform at that time. Comparing the amplitudes of these two waveforms, when the human hand 4 is detected and when only the washing water is detected, the amount of the transmitted wave reflected on the detected object is only the washing water. Is clearly smaller (since water absorbs microwaves). That is, it is possible to determine whether the washing water or the human hand 4 is obtained by observing the change rate of the amplitude. Here, the microcomputer 5 of FIG.
When the amplitude is reduced as described above by observing the change rate of the amplitude by performing the / D conversion, it is determined that a person has completed the washing, and the washing is stopped.

Since the hand 4 can be accurately detected from the degree of attenuation of the reflected wave by the substance to be detected in this manner, the moving object detection sensor unit 3 can be used in a location shown in FIG. As described above, the automatic faucet 2 may be installed at any part, so that the design of the automatic faucet 2 is also improved.

Furthermore, the detection accuracy is improved by capturing the rate of change of the frequency of the difference signal. This is because the waveform shown in FIG. 3 is observed even when only the washing water is used, but the frequency does not change so much because the change in the water discharge position, the washing water amount, and the like is small. However, when a person is washing his / her hands, the frequency is constantly changing due to all movements (4-1, 4-2, 4-3 in FIG. 4). That is, the rate of change of the frequency due to the detected object is learned, and the water discharge control is performed by comparing and analyzing the received waveform with the actual A / D received by the microcomputer 5.

[0018]

[Embodiment 3] Fig. 6 shows an example in which a moving body detection sensor is incorporated in a moving body detecting device of an automatic faucet of a wash basin, in which a transmitting section is provided in a faucet and two receiving sections are provided on a ball surface of a wash basin. It is. FIG.
FIG. 9 to FIG. 9 show transmission / reception waveforms before and after cleaning and during and after cleaning. 7 to 9, 7-1, 8-1, and 9-1 are transmission waveforms, and 7-2, 8-2, and 9-2 are reception units 12-1.
Reference numerals 7-3, 8-3, and 9-3 denote reception waveforms of the reception unit 12-2.

First, the configuration will be described. As described above in the first embodiment, the moving body detection sensor unit (the transmitting unit 1)
1 and the receiving unit 12) have the configuration shown in FIG.
Is transmitted through the signal line 6, the transmission circuit functions in response to the signal, and a signal for moving object detection is transmitted via the transmission antenna 7. The transmitted radio waves impinge on the object, part of which is reflected, part of which is absorbed, and the rest is taken into the receiving circuit via the receiving antenna 8. Here, the difference from the first embodiment is that there are a plurality of receiving units (here, two), and the receiving units are taken in by a plurality of receiving circuits.

Next, the operation will be described. The principle is that a radio wave transmitted from the transmitting unit 11 hits the human hand 4 and is reflected, and a part of the radio wave is absorbed and the rest transmits and reaches the receiving unit 12. Reduction of the radio wave that has reached the receiver 12 (attenuation)
Is measured to detect the human hand 4. The automatic faucet 2 discharges washing water toward the ball surface 1 of the sink. The trigger to start water discharge is when the receiving unit 12 of the moving object detection sensor unit detects the human hand 4.

First, the waveform of the receiving section 12-1 is usually shown in FIG.
However, when the human hand 4 enters the ball surface 1, the amplitude becomes small and the waveform becomes disturbed as shown at 8-2 in FIG. In this case, since the receiving unit 12-2 has no object that blocks the radio wave, a waveform close to the undisturbed transmission waveform is observed as shown at 8-3 in FIG.

However, at this time, it is not determined that the human hand 4 has been detected because there is no change in the signal of the other receiving unit 12-2 and the disturbance of the waveform of the receiving unit 12-1 may be due to disturbance. . Next, when the person's hand 4 comes further into the back of the ball surface 1 (far away from the place where the person stands), the waveform of the receiving unit 12-2 as well as the receiving unit 12-1 is changed as shown in FIG. 9-
As shown in FIG. 3, the waveform has a small amplitude and is disturbed. At this time, it is determined that the human hand 4 has been detected for the first time, and water discharge is started.

Stopping the water discharge is a sequence in the reverse case. However, when the waveform of only the receiving unit 12-1 is disturbed, the water discharge is not stopped. This is because, if the water discharge is stopped at this time, a problem occurs when the fingertip is being washed. In this case, the receiving unit 1
The waveforms of 2-2 and 12-3 are based on the premise that the waveform is turbulent to the extent that the washing water jumps.

In general, the greater the number of the receiving units 12, the more the degree of attenuation of the radio wave by the human hand 4 can be measured over a wide range. By analyzing the signals received by the receiving unit 12, the degree of the scattering of the washing water can be determined. Will be attached. (However, although it depends on the size of the ball surface 1, generally two places are sufficient for collecting fine data.) From these analyses, the jump that automatically adjusts the water force It is possible to realize a faucet with a small amount of water, which can contribute to providing high value-added products.

[Brief description of the drawings]

FIG. 1 is a view showing an automatic faucet installed on a wash basin.

FIG. 2 is a block diagram showing an internal configuration of a human body detection sensor unit.

FIG. 3 is a waveform of a Doppler signal of a moving object detection sensor when washing water is detected.

FIG. 4 is a waveform of a Doppler signal of a moving object detection sensor when a human hand during washing is detected.

FIG. 5 is a diagram in which an automatic faucet is installed on a wash basin.

FIG. 6 is a diagram in which an automatic faucet is installed on a washstand, and is an example in which a plurality of receiving devices are provided on a ball surface.

FIG. 7 shows transmission / reception waveforms of a moving object detection sensor in a state where no human hand is present in the wash basin.

FIG. 8 is a transmission / reception waveform of a moving object detection sensor in a state where a person is about to wash his / her hands.

FIG. 9 shows transmission / reception waveforms of the moving object detection sensor when cleaning is started.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bowl surface of wash basin, 2 ... Automatic faucet, 3 ... Movable object detection sensor unit, 4 ... Human hand, 5 ... Microcomputer, 6 ... Signal line,
7: transmitting antenna, 8: receiving antenna, 9: Doppler waveform (wash water), 10: Doppler waveform (man's hand), 11 ...
Transmission unit, 12 ... Reception unit

Claims (6)

[Claims] 1. A water discharge control device for controlling opening and closing of a water faucet installed in a wash basin, means for transmitting a radio wave for detecting a moving object, and receiving a reflected wave of the radio wave transmitted by the transmission means. Means, in a moving object detection system including a moving object detection sensor that calculates a difference between the frequency of the signal received by the receiving unit and the frequency of the signal transmitted by the transmitting unit and generates a difference signal according to the difference, A moving object detection system, wherein opening and closing of a faucet is controlled by a waveform pattern of the difference signal. 2. The moving object detection system according to claim 1, wherein the control of opening and closing the faucet is performed based on a rate of change in the amplitude of the difference signal. 3. The moving object detection system according to claim 1, wherein the control of opening and closing the faucet is performed based on a rate of change of the frequency of the difference signal. 4. A water discharge control device for controlling opening and closing of a water faucet installed in a washstand, wherein a detection area of a moving object detection sensor is provided on an upper arm side from a wrist when a user washes a palm. Motion detection system. 5. A transmitting means is provided in a faucet installed in a washstand, a receiving means is provided in a portion facing the transmitting means, and an attenuation rate of the transmission wave in the receiving means is measured. A moving object detection system that controls opening and closing of a faucet. 6. The faucet according to claim 5, wherein a plurality of said receiving means are installed, and a faucet opening / closing control is performed by measuring an attenuation state of each received wave received by said receiving means. Motion detection system.