KR20030064127A - Sensing device opening and closing of the door and method for sensing thereof - Google Patents

Abstract

PURPOSE: An apparatus for sensing the open and close of the door and a method for sensing the same are provided to sense the status of the door open and close more effectively and more accurately. CONSTITUTION: An apparatus for sensing the open and close of the door includes a sensing block(31), an offset voltage output block(33), an amplifying block(35), a filter block(37), a micro controller(39) provided with a plurality of discriminating blocks(39a,39b,39c) and an alarm signal output block(41). In the apparatus for sensing the open and close of the door, the sensing block(31) detects the frequency change in response to the neighboring environment change, the amplifying block(35) outputs the output signal of the sensing block(31). The filter block(37) passes only the frequency having a predetermined bandwidth from the output signal of the amplifying block(35). The alarm signal output block(41) outputs the offset voltage of the sensing block(31), the filter block(37) and the filter block(37). And, the micro controller(39) determines whether the frequency change sensed by the sensing block(31) is due to the open and close of the door or not.

Description

Sensing device opening and closing of the door and method for sensing pretty}

The present invention relates to a system for detecting a change in the surrounding environment, and more particularly, to a door opening and closing detection device and a detection method to remove the malfunction of the device by detecting the door more effectively and precisely.

In general, the door opening and closing detection device uses a sensor to detect the opening and closing of the door, these sensors can be classified in various ways according to the use, in particular, the sensor used in the alarm, such as an optical sensor using infrared rays, and the like to impact It can be classified into a shock sensor that operates by, a current sensor using a magnet and a reed switch, and a thermal sensor that detects infrared rays emitted from the human body.

However, the light sensor is susceptible to pollution and is susceptible to disturbance light, and its characteristics are changed by ambient temperature, so it requires additional safety devices for infrared detection and installation difficulties, and the shock sensor malfunctions due to external force. This is a severe disadvantage.

In addition, when the current sensor is used for an alarm, there is no preventive measure for cutting the wire to avoid the detection of the current sensor, and the thermal sensor detects infrared rays emitted from the human body, so the behavior radius in the room is limited. In practical terms, there were a number of problems.

In addition, when the existing sensors are applied to various alarms, for example, when installed in a vehicle, a sensor must be installed at each door or trunk, and the sensors are installed at the door as well as at the door in the home. There was a hassle to install.

On the other hand, in addition to the sensor as described above, the signal generated by the opening and closing of the door and the impact or vibration is amplified to a sufficient size using a microphone, and the low-frequency signal generated during the opening and closing of the door to detect whether the door is opened or closed A door open / close detection device has been proposed to detect and warn a user.

Hereinafter, a door open / close detection device according to the prior art will be described with reference to the accompanying drawings.

1 is a block diagram of a door open and close detection device according to the prior art.

As shown in FIG. 1, the conventional door open / close detection device includes a sensor unit 1 for detecting a frequency generated when the door is opened and closed, and a frequency detected by the sensor unit 1 to be suitable for signal processing. An amplification section 3 for amplifying the width, a low pass filter 5 for passing only a low frequency signal similar to when the door is opened or closed in the output signal of the amplification section 3, and the low pass filter ( And a one-chip processor 7 for determining whether the low-frequency signal output from 5) is a low-frequency signal generated by opening and closing of the door, and an alarm unit 9 for outputting a warning sound to the user under the control of the one-chip processor 7. do.

Here, the sensor unit 1 is a condenser microphone in which different voltages are generated according to displacements moving from the stop position of the vibrating membrane at the anode of the condenser so that a specific frequency propagated by the pressure change of the medium is detected as the voltage change. The amplifier 3 is composed of an op amp for amplifying a minute detection signal output from the condenser microphone to a predetermined width.

The amplifier 3 includes a battery detector (not shown) that detects a battery state and transfers the same to a one-chip processor.

The one-chip processor (7) has a built-in A / D converter (not shown) for converting the analog electric signal output from its own memory and low-pass filter (5) into a digital signal, the 8-bit A / D converter is a micro Microchip's PIC16C770, which employs Chip's PIC16C711 or 12-bit A / D converter, is used.

The door opening and closing detection apparatus according to the related art, which is configured as described above, first detects a change in frequency detected through a medium (air) in the sensor unit 1 configured as a condenser micro, and the sensor unit 1 in the amplification unit 3. Output signal is amplified to a predetermined width so as to be suitable for signal processing.

Thereafter, the low pass filter 5 passes only a band (4-12 Hz or 17-25 Hz) similar to the low frequency signal generated when the door is opened or closed in the output signal of the amplifying unit 3 and passes through the A of the one-chip processor 7. / D is applied to the input terminal of the converter.

In this case, the A / D converter performs a sampling process to process the analog signal of the low frequency generated when the door is opened or closed as a digital signal, and the one-chip processor 7 uses the waveform Sn of the sampled signal as a reference value ( Vref) to determine whether the current frequency detected by the sensor unit 1 is a low frequency signal or noise due to the opening and closing of the door.

That is, when the waveform Sn of the sampled signal is located below the reference value Vref, the sampling number Np increases the sampling number Np one by one while the number of samplings when the door is opened or closed is increased. If it is greater than or equal to the mean sampling number Nr, it is finally determined that the frequency detected by the current sensor unit 1 is the frequency generated due to the door opening and closing.

For reference, as illustrated in FIG. 2, the one-chip processor includes a driving circuit for driving a chip and various signal lines. The driving circuit includes an oscillation circuit 21 for generating a clock and a power supply to the chip. The power supply circuit section 23 to be applied, the reset section 25 for resetting the operation of the chip, and the switching section 27 for setting the operation mode of the one-chip processor 7 are provided.

Referring to the operation of the conventional door opening and closing detection device as follows.

First, when the door open / close detection device is operated, the battery detection unit (not shown) in the amplifying unit 3 detects the power charged in the battery, determines whether it is charged with a power that can operate normally, and then the result is one chip. Transfer to processor 7.

If the power of the battery does not allow the door open / close detection device to operate normally, the one-chip processor 7 controls the alarm unit 9 to notify the user of the battery check signal, thereby preventing abnormal operation due to battery voltage. do.

On the other hand, if the battery power is normal, the sensor unit 1 constituted by the condenser micro senses the pressure change in the room, and the sensed signal is sequentially turned on the amplifying unit 3 and the low pass filter 5 as described above. The one chip processor 7 is input to the one chip processor 7, and the one chip processor 7 determines whether the door is opened or closed based on the signal input from the low pass filter 5.

Here, the method of determining whether the door is opened or closed by the one-chip processor will be described with reference to the flowchart shown in FIG. 3.

As shown in FIG. 3, first, an initial value is set (S301). The initial value includes a sampling number Nr used as a reference value to determine that the sampling number Np obtained by sampling the analog signal output from the low pass filter 5 from the A / D converter is the sampling number when the door is opened or closed. And a reference value Vref for determining whether to perform a process of determining whether the waveform of the signal output from the low pass filter 5 is due to the opening or closing of the door.

Thereafter, the one-chip processor 7 compares the waveform Sn of the signal sampled by the A / D converter with the reference value Vref (S302), so that the waveform Sn of the sampled signal is greater than the reference value Vref. If it is small, the number of sampling numbers is increased one by one until the sampling number Np of the waveform is equal to or larger than the sampling number Nr used as the reference value (S303).

Thereafter, when the sampling number Np, which has been increased one by one, is equal to or larger than the sampling value Nr used as the reference value, it is determined (S304), and when the time point is detected, the frequency detected by the current sensor unit 1 is determined. Determines that the frequency generated by the door opening and closing (S305).

Thereafter, the one-chip processor 7 controls the warning unit 9 to output a warning signal that can be recognized by the user (S306), and then determines whether to input the reactivation signal of the device (S307). If there is a signal input, the sampling number Np is reset (S308), and the above process is repeated from step S302 to detect and determine whether the door is opened or closed.

However, the conventional door opening and closing detection device and the detection method have a problem that the sensitivity is severely changed according to the surrounding environment, and the amplification degree is so large that the malfunction becomes severe or the signal is too small to detect. That is, since the one-chip processor only determines whether the door is opened or closed based on the signal output from the low pass filter, the accuracy is reduced by that, and the reliability of the door open / close detection device is greatly reduced due to frequent malfunctions.

The present invention has been made to solve the above problems of the prior art, and an object of the present invention is to provide a door opening and closing detection device and a detection method suitable for detecting whether the door is opened and closed more effectively and precisely.

Another object of the present invention to provide a door opening and closing detection device and a detection method that can prevent the malfunction of the device by accurately determining whether the door is opened or closed through the data collected through various paths and thereby improve the reliability of the device. have.

1 is a block diagram of a door open and close detection device according to the prior art

2 is a block diagram of a one-chip processor according to a conventional door opening and closing detection device

3 is a flow chart for explaining a door open and close detection method according to the prior art

4 is a block diagram of a door open / close detection device according to a first embodiment of the present invention;

5 is a detailed circuit diagram of FIG.

Figure 6 is an output waveform diagram of the filter unit for a daily environment without opening and closing of the door

7 is an output waveform diagram of the filter unit when opening and closing the door

8 is an output waveform diagram of a filter unit for explaining the half-period measurement of the waveform according to the door opening and closing detection method of the first embodiment of the present invention

Figure 9a is a waveform (MS) output from the filter unit for the everyday environment

Figure 9b is a waveform (MS) output from the filter unit according to a large change in the external environment, such as opening and closing of the door for explaining the application of the MPV according to the door opening and closing detection method of the first embodiment of the present invention

10A is an output waveform diagram of an amplifier according to a door open / close detection device according to a first embodiment of the present invention;

10B is an output waveform diagram of the filter unit according to the door open / close detection device according to the first embodiment of the present invention.

11 is a flowchart for explaining a door open / close detection method according to the first embodiment of the present invention.

12 is a block diagram of a door open / close detection device according to a second embodiment of the present invention;

13 is a detailed circuit diagram of FIG.

14 is a waveform diagram of a low frequency signal for explaining a door open / close detection method according to a second embodiment of the present invention;

15 is a view showing a change in the waveform (MS) output from the filter unit for the everyday environment to explain the door opening and closing detection method according to a second embodiment of the present invention

16 is a flowchart illustrating a door open / close detection method according to a second embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

31 sensor unit 33 offset voltage output unit

35: amplification unit 37: filter unit

39: microcontroller 100: sensitivity adjustment unit

Door opening and closing detection apparatus according to an embodiment of the present invention for achieving the above object is a sensor unit for detecting a frequency change according to the change of the surrounding environment, an amplifier for amplifying the output signal of the sensor unit, the output of the amplification unit A filter unit for passing only a frequency of a predetermined band from a signal, an offset voltage output unit for outputting an offset voltage to the sensor unit, an amplifier unit, and a filter unit, and receiving the output signals of the amplifier unit, the filter unit, and the offset voltage output unit; And a microcontroller configured to determine whether the frequency change detected by the unit is due to the opening and closing of the door. The door opening and closing method may include a first step of detecting a frequency change according to a change in the surrounding environment, and A second step of amplifying the signal and filtering only a predetermined bandwidth; and amplifying the signal, the filtered signal, and amplifying the signal. That by using the offset voltage for filtering said detected signal comprises a third step of determining whether due to the opening and closing of the door is characterized.

In addition, the door opening and closing detection apparatus according to another embodiment of the present invention is a sensor unit for detecting a frequency change according to the change of the surrounding environment, an amplifier for amplifying the output signal of the sensor unit, and the output signal of the amplification unit of a predetermined band A filter unit for passing only a frequency, an offset voltage output unit for outputting an offset voltage to the sensor unit, an amplifier unit, and a filter unit, and waveforms positioned at either one of the waveforms output from the filter unit with reference to the offset voltage A microcontroller for determining whether the door is opened or closed through mutual comparison between the areas, and specifying the specific range to input the microcontroller to determine that the door is opened or closed when a difference between the areas exists within a specific range. It is configured to include a sensitivity adjustment unit, the door opening and closing detection method according to the change according to the surrounding environment A first step of detecting a different frequency change, a second step of amplifying the detected signal and filtering only a predetermined bandwidth, and waveforms positioned on either side of the waveform output from the filter unit based on an offset voltage And a third step of determining whether the door is opened or closed through mutual comparison between the areas.

The door open / close detection device and the detection method according to the embodiment of the present invention having the technical features as described above are characterized in that the microcontroller can make a more precise judgment by pluralizing data necessary for determining the change of the surrounding environment. To this end, the door open / close detection device of the present invention includes an offset voltage output unit for outputting an offset voltage to a sensor unit, an amplifier unit, and a filter unit, and outputs the output signals of the offset voltage output unit, the amplifier unit, and the filter unit to the microcontroller. As a result, the microcontroller can more accurately determine whether the door is opened or closed based on a plurality of input signals.

In addition, the door opening and closing detection apparatus and detection method according to another embodiment of the present invention is characterized in that the microcontroller can calculate the change in the area of the waveform according to the change of the surrounding environment to more accurately determine whether the door is opened or closed. There is this. That is, the area of the waveforms located on either side of the waveform of the signal output from the current filter unit is calculated, and the calculated area is compared with each other to determine whether the door is opened or closed using the change width of the area.

Hereinafter, a door open / close detection device and a detection method according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

First embodiment

4 is a block diagram of a door open / close detection device according to a first embodiment of the present invention, and FIG. 5 is a partial detailed circuit diagram of the block of FIG. 4.

4 and 5, the door opening and closing detection apparatus according to the first embodiment of the present invention is large, the sensor unit 31 for detecting a change in frequency according to the sound and air flow of the surrounding, and the sensor An offset voltage output unit 33 for outputting an offset voltage to the unit 31, an amplifier 35, a filter unit 37, and a microcontroller 39, and an output from the offset voltage output unit 33 The amplifier 35 amplifies the output signal of the sensor unit 31 with a predetermined width based on the offset voltage, and receives only the frequency band set based on the offset voltage based on the output signal of the amplifier 35. And a micro controller 39 for determining whether the door is opened or closed from the output signal of the offset voltage output unit 33, the amplifying unit 35, and the filter unit 37. .

Here, the sensor unit 31 is made of a condenser microphone for detecting a frequency change according to the ambient sound and air flow using the offset voltage output from the offset voltage output unit 33 as an operating voltage.

The amplifier 35 amplifies the output signal of the sensor unit 31 to a predetermined width based on the offset voltage within the operating voltage range Vcc to GND. That is, the amplifier 35 is composed of OP-Amp, amplifies the output signal of the sensor unit 31 corresponding to the difference between the voltage input to the positive (+) terminal and the negative (-) terminal, the offset Amplified based on the offset voltage output from the voltage output unit 33, and outputs the amplified signal to the filter unit 37 and the microcontroller 39. For reference, the amplification unit 35 is preferably configured of the National LM2902 OP-Amp, the frequency range is a range that can be supported by the LM2902 OP-Amp from a few Hz to several tens of MHz.

The filter unit 37 is a low pass filter that passes only a frequency band set based on an offset voltage in the output signal of the amplifier 35. The filter unit 37 is preferably configured of National LM2902. The signal filtered by the filter unit 37 is input to the microcontroller 39.

The microcontroller 39 measures the time during the half period of the signal waveform output from the filter unit 37 to determine whether the current output signal of the filter unit 37 is the frequency of the band due to the opening and closing of the door. 1 is a signal output from the filter unit 37 by comparing the waveform output from the determination unit 39a with the waveform output from the filter unit 37 and a predetermined maximum peak voltage (MPV), or In the present invention, the second discriminating unit 39b for determining whether the room is a general noise (in the present invention, all frequencies other than the frequency of the band due to opening and closing of the door is defined as noise) and the amplifying unit 35 And a third discriminating unit 39c which compares the output signal with the output signal of the filter unit 37 and determines whether the output signal of the filter unit 37 is due to the opening or closing of the door or is noisy. .

Here, the MPV (Maximum Peak Voltage) is a value set below or above a peak value of the peak value of the waveform MS output from the filter unit 37 measured in a normal environment (an embodiment of the present invention). Is set below the peak value of the MS waveform), and the MPV is set to an optimal value obtained through experiments.

The microcontroller 39 also includes a 12-bit A / D converter (not shown) for converting an analog signal input from the amplifier 35, the filter 37, and the offset voltage output unit 33 into a digital signal. Include.

In addition, the door open / close detection device of the present invention outputs a signal that can be recognized by the user when the microcontroller 39 determines that the signal currently detected by the sensor unit 31 is due to the opening / closing of the door. It may further include a warning signal output unit.

When the door opening and closing detection device of the present invention configured as described above detects a frequency according to the change of the surrounding situation in the sensor unit 31 and transmits the frequency to the amplifier 35, the amplifier 35 in the offset voltage output unit 33. The signal output from the sensor unit 31 is amplified to a predetermined width based on the output offset voltage.

The output terminal of the amplifier 35 is connected to the input terminal of the filter unit 37 and the input terminal of the microcontroller 39 so that the signal amplified by the amplifier 35 is transferred to the filter unit 37 and the microcontroller 39. In response thereto, the filter unit 37 passes only a frequency band set on the basis of the offset voltage output from the offset voltage output unit 33 from the output signal of the amplifier unit 35, and then passes it through the microcontroller 39. To pass).

The microcontroller 39 determines whether the frequency detected by the sensor unit 31 from the output signals of the amplifying unit 35, the filter unit 37, and the offset voltage output unit 33 is due to the opening and closing of the door. If not, it is determined by simple ambient noise, indoor movement and voice.

In addition, when the warning signal output unit 41 is configured, the microcontroller 39 determines that the frequency detected by the current sensor unit 31 is due to the opening and closing of the door. By controlling the control to output a warning signal that can be recognized by the user.

The door open / close detection device and the detection method according to the first embodiment of the present invention will be described in detail as follows.

In the driving of the door open / close detection device according to the first embodiment of the present invention, the initial value of various variables required for largely determining whether the door is opened or closed is detected, and after detecting the frequency according to the change of the surrounding environment, The operation of determining whether the door is opened or closed using the initial values of the predetermined variables is performed.

First, the initial value has an offset voltage and, as mentioned earlier, the MPV (Maximum) set below a predetermined value relative to the peak value of the signal waveform output from the filter unit 37 in a normal environment without opening and closing of the door. Peak Voltage) and min_time and max_time, which are standard values for determining whether the door is opened or closed by measuring the time during the half cycle of the waveform, are set to the optimum values obtained by repeated experiments.

As such, when the initial value setting of the various variables is completed, the signal output from the current filter unit 37 is output from the initial value, the offset voltage, the output signal of the amplifier 35, and the output signal of the filter unit 37. An algorithm for determining whether the noise is caused by opening or closing is described in detail as follows.

In general, the output waveform MS of the filter unit 37 is shown in FIG. 6 in the normal environment without opening and closing of the door. That is, in a daily environment without opening and closing of the door, it can be seen that the waveform of the signal output from the filter unit 37 is almost unchanged when viewed based on the offset voltage, which is a high frequency signal generated in the daily environment. This is because they are all removed when passing through the filter part 37.

On the contrary, when there is an opening / closing operation of the door, as shown in FIG. 7, it can be seen that the output waveform of the filter unit 37 varies greatly with respect to the offset voltage. That is, the output waveform MS of the filter unit 37 has a ripple up and down based on the offset voltage, and this type of waveform has a half period (2 / T), and the half period is approximately 250 msec to 50 msec. Is in the range of. Of course, there is a slight difference in half-cycle depending on the shape and size of the door.

Here, by measuring the half period of the waveform (MS) output from the filter unit 37 can know the frequency of the waveform, as shown in Figure 8, by measuring the time during the half period of the waveform by using a timer The frequency can be calculated and, with the exception of some specific signals, the half period of the waveform is in the range of approximately 250 msec to 50 msec, so the frequency ranges from 2 to 10 Hz.

In this way, by measuring the half period of the waveform output from the filter unit 37, and calculates the frequency based on it to determine whether the frequency detected by the sensor unit 31 is due to the opening and closing of the door or the noise generated in the daily environment Can be determined

Meanwhile, various types of noise may be generated according to the surrounding environment, and the low frequency signal included in the noise is similar to the low frequency signal due to the opening and closing of the door based on only the offset voltage. If it is determined that the door is opened and closed only with this frequency, this may be a malfunction.

Therefore, in order to completely eliminate such a malfunction, the peak value of the waveform output from the filter unit 37 for the everyday surrounding environment is detected, and the maximum peak voltage (MPV) positioned below a predetermined value with respect to the peak value of the waveform. ) Is set to an appropriate value through several experiments, and then compares the waveform output from the current filter unit with the preset MPV.

For reference, FIG. 9A illustrates a waveform MS output from the filter unit for a daily environment, and FIG. 9B illustrates a relationship between the waveform MS output from the filter unit and the preset MPV when the door is opened and closed. To illustrate.

As can be seen from the above figure, the waveform MS outputted from the filter unit may be located above and below when compared with MPV.

Here, when the waveform output from the filter unit 37 is located at least once below the MPV at least once in a half period, it means that a waveform larger than the waveform that can be output in the normal environment is input. This means that the peak value of the waveform is larger than that of the waveform in the normal environment.

For reference, in the exemplary embodiment of the present invention, the MPV may be set below the offset voltage, or the MPV may be set above the offset voltage. That is, when the MPV is set upward based on the offset voltage, when the waveform MS output from the filter unit 37 is positioned above the MPV at least once in a half period, it is more than the waveform output in the ordinary environment. It can be recognized that a large waveform is input.

In this way, by checking the position of the waveform output from the filter unit 37 on the basis of the MPV, it is possible to know how many times the waveform currently output from the filter unit 37 is below (or above) the MPV. . Fortunately, however, the peak value of the waveform output from the filter unit 37 is very small compared to the MPV in the ordinary environment, so that the opening and closing of the door can be more precisely determined by adjusting the MPV to an appropriate value.

On the other hand, since the waveform of the signal (noise) output from the filter unit 37 when the loud sound in the room appears in the form almost similar to the waveform of the signal output from the filter unit 37 when the door is opened and closed the filter unit If the signal output from (37) is not a low frequency signal or noise due to the opening or closing of the door, the noise is incorrectly mistaken as a door opening or closing, so that a malfunction occurs.

In other words, the noise may include a low frequency signal of a band similar to the low frequency signal generated when the door is opened and closed. When the noise passes through the filter unit 37, the high frequency signal is removed and only the low frequency signal is output.

Accordingly, in the present invention, the waveform VS of the signal output from the amplifier 35 to the filter unit 37 (see FIG. 10A) and the waveform MS output from the filter unit 37 (see FIG. 10B) are shown. By comparing with each other, it is clearly determined what waveform the waveform output from the filter section 37 is.

That is, before the noise including the low frequency signal similar to that when the door is opened or closed passes through the filter unit 37, that is, the output signal of the amplifier unit 35 contains many high frequencies (see FIG. 10A). Even though the filter 37 does not pass through the same, there is a remarkable difference from the low frequency signal output from the amplifier 35 when the door is opened or closed.

Therefore, when the microcontroller 39 compares the output signal VS of the amplifier 35 and the output signal of the filter 37, the low-frequency signal currently output from the filter unit 37 may open or close the door. It is possible to more clearly determine whether the signal is a low frequency signal or a low frequency signal included in noise.

As described above, the door open / close detection method according to the first exemplary embodiment of the present invention detects a frequency by detecting a time during a half period of the waveform output from the filter unit in the microcontroller, and compares the waveform output from the filter unit with the MPV. By comparing the output waveforms of the amplifier and the output waveforms of the filter, any one of them does not satisfy the condition and is not judged as a low frequency signal due to opening and closing of the door.

Therefore, the low frequency signal due to the opening / closing of the door and the low frequency signal in the everyday environment can be discriminated more precisely, thereby preventing the malfunction of the apparatus.

Hereinafter, a door open / close detection method according to a first embodiment of the present invention will be described with reference to the flowchart of FIG. 11.

As shown in FIG. 11, first, initial values (MPV, min_time, max_time, VS_limit) required for detecting door opening and closing are set (S111). For reference, VS_limit means a reference value for detecting how many times the waveform output from the amplifier 35 changes up and down based on the offset voltage.

Then, when the offset voltage, the output signal of the amplifier 35 and the output signal of the filter unit 37 is input to the microcontroller 39 (S112), the microcontroller 39 is currently output from the filter unit 37 Comparing the waveform (MS) of the signal to the offset voltage (S113), if the waveform (MS) is located below the offset voltage, the timer for measuring the time during the half period of the waveform (MS) is operated (S114).

Thereafter, the waveform MS of the signal output from the filter unit 37 is compared with the MPV (S115). When the waveform MS is positioned below the MPV, the waveform MS is positioned below the MPV. After setting the flag of the register, i.e., the peak flag Peak_flag, to 1 (S116), the waveform VS of the signal output from the amplifying unit 35 is set several times based on the offset voltage. It counts whether it changes up and down (S117). At this time, as a result of comparing the waveform MS of the signal output from the filter unit 37 and the MPV, if the waveform MS is not below the MPV, the waveform of the signal output from the amplifier 35 immediately ( VS) is counted.

Thereafter, the microcontroller 39 determines whether the waveform VS of the signal output from the amplifier 35 has to change up and down how many times based on the offset voltage to determine noise. 35) compares the number of ripples (VS_count) appearing in the waveform VS of the signal output from 35) with the reference value VS_limit (S118). If the value of VS_count is smaller than the value of VS_limit, VS_flag is set to 1 (S120).

For reference, the VS_flag means a flag of a register for storing a result of comparing a value of VS_count and a value of VS_limit, and the VS_limit is set to an optimal value obtained by an experiment.

Subsequently, if 1 or 0 is set to the VS_flag, the processes from S113 to S120 are repeatedly performed during the half period of the waveform of the signal output from the filter unit 37.

Subsequently, repeatedly performing step S120 to step S120, that is, comparing the waveform MS of the signal output from the filter unit 37 and the offset voltage PRV in step S113, the waveform is performed. The point at which MS rises above the offset voltage comes out, which is when the half cycle of waveform MS ends.

Therefore, when the waveform MS of the signal output from the filter unit 37 is positioned above the offset voltage, the microcontroller 39 recognizes that the half cycle of the waveform MS is finished and turns off the operation of the timer. (S121).

Thereafter, the microcontroller 39 checks whether the time during the half period of the waveform MS checked by the timer is within a range of min_time and max_time which are initial values with respect to a preset time (S122). If present, the signal output from the current filter unit 37 is determined to be a low frequency signal due to the opening and closing of the door, and it is immediately checked whether the value of Peak_flag is "1" or "0" (S123). In this case, if the time during the half period of the waveform MS checked by the timer is not within the range of the initial value min_time and max_time, it is not necessary to check the value of Peak_flag by determining that the signal is not caused by the opening and closing of the door.

Subsequently, when the value of the Peak_flag is checked and the value is "1", it is determined that the signal output from the current filter unit 37 is a low frequency signal due to the opening / closing of the door, and the value of VS_flag is "1". Check whether it is (S124). In this case, when the value of Peak_flag is "0", it is not necessary to determine VS_flag by determining that the signal output from the current filter unit 37 is a low frequency signal generated in a normal environment.

Thereafter, when the value of the VS_flag is checked and the value is "1", it is determined that the waveform of the signal currently output from the filter unit 37 is a low frequency signal resulting from the opening and closing of the door (S125).

As described above, the door open / close detection method according to the first embodiment of the present invention determines that the low-frequency signal resulting from the opening / closing of the door is finally performed in step S125, and thus the half-period of the waveform checked by the timer made in step S122. The time must be within the preset initial range of min_time and max_time, and all three conditions must be satisfied that the Peak_flag value must be "1" and the VS_flag value must be "1". It can be seen that it is determined that the signal is a low frequency signal due to the opening and closing of. Therefore, if any one of the above three conditions is not satisfied, it is determined that the signal output from the current filter unit 37 is not caused by opening or closing of the door but is a low frequency signal generated in a normal environment.

Subsequently, after checking whether the device is re-operated (S126), when the re-activation signal is input, after resetting variables such as each flag (Peak_flag, Vs_flag) set in the previous process (S127), the filter unit 37 From the step S113 of comparing the waveform and the offset voltage of the signal output from the step again to repeat the above process.

In addition, when a warning signal output unit for selectively outputting a warning signal to a user is configured according to whether the door is opened or closed, the microcontroller 39 outputs a warning signal only when all three conditions are satisfied. The controller controls the unit to output a warning signal in a form recognizable by the user.

Second embodiment

In the above-described first embodiment of the present invention, a change in the surrounding environment is detected using a frequency, but the second embodiment of the present invention uses a change in the waveform itself, that is, a change in the area of the waveform due to the change in the amplitude of the waveform. There are technical features to detect changes in the environment.

12 is a block diagram illustrating a door open / close detection device according to a second embodiment of the present invention, and FIG. 13 is a detailed circuit diagram of FIG. 12.

12 and 13, in the door open / close detection device according to the second embodiment of the present invention, the sensitivity adjusting unit 100 is added as compared with the first embodiment, and the other parts are the first. The same parts as in the embodiment will be described with the same reference numerals.

12 and 13, the door opening and closing detection apparatus according to the second embodiment of the present invention is large, the sensor unit 31 for detecting the frequency according to the sound and air flow of the surrounding, and the sensor unit An offset voltage output unit 33 for outputting the offset voltage to the amplifier 31, the filter unit 37, and the microcontroller 39, and an offset output from the offset voltage output unit 33. The amplifier 35 amplifies the output signal of the sensor unit 31 with a predetermined width based on the voltage, and receives only the output signal of the amplifier 35, and passes only the frequency band set based on the offset voltage. After calculating the area of the waveform which is located below or above the filter unit 37 and the waveform output from the filter unit 37 based on the offset voltage, the area of the door by comparing the area of the previous waveform and the area of the current waveform Micro to judge the opening and closing And a sensitivity adjusting unit 100 for adjusting the sensitivity by adjusting the voltage value input to the controller 39 and the microcontroller 39 using a variable resistor.

Here, the sensitivity adjusting unit 100 configures the variable resistor Vr between the operating voltage Vcc and the ground voltage GND, and adjusts the value of the variable resistor to adjust the value of the voltage input to the microcontroller 39. Adjust it. Therefore, the microcontroller 39 compares the width of the area of the detected waveform with respect to the voltage determined by the sensitivity adjusting unit 100, and determines whether the door is opened or closed when the width of the area changes. As a result, the sensitivity of the door open / close detection device can be adjusted by adjusting the variable resistance of the sensitivity adjusting unit 100.

The sensor unit 31 is formed of a condenser microphone for detecting a change in frequency according to ambient sound and air flow using the offset voltage output from the offset voltage output unit 33 as an operating voltage.

The amplifier 35 amplifies the output signal of the sensor unit 31 to a predetermined width based on the offset voltage within the operating voltage range Vcc to GND. That is, the amplifier 35 is composed of OP-Amp, amplifies the output signal of the sensor unit 31 corresponding to the difference between the voltage input to the positive (+) terminal and the negative (-) terminal, the offset Amplified based on the offset voltage output from the voltage output unit 33, and outputs the amplified signal to the filter unit 37. For reference, the amplification unit 35 is preferably configured of the National LM2902 OP-Amp, the frequency range is a range that can be supported by the LM2902 OP-Amp from a few Hz to several tens of MHz.

The filter unit 37 is a low pass filter that passes only a frequency band set based on an offset voltage in the output signal of the amplifier 35. The filter unit 37 is preferably configured of LM2902 manufactured by National. The signal filtered by the filter unit 37 is input to the microcontroller 39.

The microcontroller 39 includes a 12-bit A / D converter (not shown) for converting an analog signal input from the filter unit 37 and the offset voltage output unit 33 into a digital signal.

In addition, the door open / close detection device of the present invention outputs a signal that can be recognized by the user when the microcontroller 39 determines that the signal currently detected by the sensor unit 31 is due to the opening / closing of the door. It may further include a warning signal output unit 41.

When the door open / close detection device according to the second embodiment of the present invention configured as described above detects a frequency according to a change in the surrounding situation in the sensor unit 31 and transmits the frequency to the amplifier 35, the amplifier 35 may offset the voltage. The signal output from the sensor unit 31 is amplified to a predetermined width based on the offset voltage output from the output unit 33.

The output terminal of the amplifier 35 is connected to the input terminal of the filter unit 37 so that the signal amplified by the amplifier 35 is input to the filter unit 37, whereby the filter unit 37 is an amplifier unit ( Only the frequency band set on the basis of the offset voltage output from the offset voltage output unit 33 from the output signal of 35) is passed, and then it is transmitted to the microcontroller 39.

The microcontroller 39 calculates an area of a waveform located below or above a waveform based on an offset voltage from a waveform of a signal output from the filter unit 37 (in the second embodiment of the present invention, the waveform located below). Each waveform is grouped into a plurality of groups, the areas of the waveforms belonging to each group are summed, and compared with the total value of the areas belonging to the previous group, and if the difference is large, the door is opened or closed. I think it is a change of environment.

The door opening / closing detection method according to the second embodiment of the present invention configured as described above can detect the change of the waveform, that is, the amplitude, and determine whether the environment changes according to the degree of the change.

In other words, the signal passing through the filter unit 37 is a low frequency signal that changes up and down based on the offset voltage in a normal environment, but when the opening and closing of the door or other sudden change of the surrounding environment occurs, the amplitude increases accordingly. The waveform will appear. The change may be instantaneous or last for a long time, but eventually it will revert to the shape of the waveform in the initial everyday environment.

FIG. 14 illustrates waveforms of a low frequency signal for explaining a door open / close detection method according to a second embodiment of the present invention. Notice that there is a downward waveform. At this time, the peak point of the downward waveform becomes A point and B point. When such a waveform is sampled by the A / D converter in the microcontroller 39, it has a predetermined number of sampling times.

Therefore, when the peak value of each waveform is connected to the intersection point of the offset voltage with respect to the waveform located below the offset voltage, the base and height of the triangle can be obtained. Therefore, the approximate area of each waveform can be obtained. By using this change in area, it is possible to determine whether the waveform of the signal currently output from the filter unit 37 is due to the opening / closing of the door or in a normal environment.

This will be described in more detail as follows.

FIG. 15 illustrates a change in the waveform MS output from the filter unit in a daily environment, in which the peak points of the waveforms are A, B, C, D, and E points. For example, the peak point A is the offset voltage. Start and sample until it reaches A "point and then calculate the number of samplings at that time. When the waveform passes A" point, the peak point check is terminated and when it crosses B 'point, peak point check is performed. You can get the position of the peak point B by starting and continuing until you reach the point B ". By repeating this process, you can find the peak points of each waveform below the offset voltage.

At this time, if the surrounding environment changes suddenly due to the opening and closing of the door, a waveform with a large amplitude comes out as in the fourth waveform. This waveform also obtains the peak point D through the above-described process, and each peak point is set to the offset voltage. You can find the area of each waveform by connecting it to the point that changes from bottom to top.

As such, after the area is obtained for each waveform, when a waveform having a large area rapidly changing than the area of the previous waveform is detected by comparing the area of the previous waveform with the area of the current waveform, the surrounding environment is caused by the opening and closing of the door. I think it changed drastically.

Here, in order to more clearly and accurately determine whether the door is opened or closed, in the second embodiment of the present invention, the waveforms are grouped into a plurality of groups, and then all the areas of the plurality of waveforms belonging to the group are summed up to one value (Sref). ), And add up the area of the plurality of waveforms belonging to the next group, and compare the summed value with the previous value. .

The door opening / closing detection method according to the second embodiment of the present invention will be described in detail with reference to the flowchart of FIG. 16 as follows.

As shown in FIG. 16, in order to determine whether the door is opened or closed, the reference value Sref and the sensitivity adjusting unit 100 are summed up by adding together the areas of the N waveforms output from the filter unit 31 under ordinary circumstances. A variable Delta or the like relating to the set sensitivity is set (S161).

Then, while increasing the number of counts for checking whether the life of the battery is sufficient to perform the algorithm for door opening and closing detection by one (S162), which means a cycle for checking the battery counted each time Compare with Check_period (S163).

As a result of the comparison, when the counted value reaches the battery check period (Check_period), it is determined that the current battery state is not sufficient voltage to determine the door opening and closing (S164), and the counted value is the If the battery check cycle has not been reached, the following process is performed to detect the opening and closing of the door.

That is, if the count value does not reach the check period (Check_period) of the battery, whether the waveform currently output from the filter unit 37 is located below or above the offset voltage, so-called waveform The position is checked (S165). Here, the reason for checking whether the waveform output from the filter unit 37 is located below or above the offset voltage is because if the waveform currently output from the filter unit 37 is located below the offset voltage ( Positon = 1), sampling must be continued to find the peak point of the corresponding waveform. On the contrary, if the waveform output from the current filter unit 37 is positioned upward based on the offset voltage, the peak point check is stopped and immediately before. This is because we need to calculate the area of the waveform we sampled at.

As such, when the position of the waveform is checked as "1" (S166), the sampling value for finding the peak point of the waveform is increased one by one, and check_flag is set to "0" (S167). Go back to step In this case, the check_flag is a variable so that the area calculation is not duplicated when the current waveform changes upward based on the offset voltage.

On the other hand, if the position variable is not "1" as a result of checking the position of the waveform, it is determined that the waveform currently output from the filter unit 37 is located above the offset voltage, and the waveform located above the area Since there is no need to obtain the value, the value of check_flag that does not need to calculate the area is set to "1" (S168). In other words, if the value of the check_flag is "1", the area is not calculated any more, and the area of the waveform sampled previously is obtained (S169).

In other words, the peak value of the previously sampled waveform is obtained, and then the area of the waveform is calculated based on this, and the area is accumulated in area_sum. The process of obtaining and accumulating the area of the waveform is a variable representing the peak value of the waveform. It is repeatedly performed until the value of peak_count becomes a reference value (in the embodiment of the present invention, the peak_count is set to "4").

In other words, the peak value of the waveform is obtained, the area of the waveform is calculated based on the waveform, and the obtained area is accumulated. The area of the waveforms to be accumulated depends on how many waveforms are grouped into one group. Whether the area of the belonging waveforms is obtained can be known by checking the number of peaks of the obtained waveforms.

Therefore, as described above, if the value of peak_count, which is a variable representing the peak value of the waveform required to obtain the area, is checked (170), and the value is less than "4", step S162 until the value of peak_count becomes "4". Returning to, repeat the previous process, and if the value of the peak_count is "4", it is determined that the area of the waveforms belonging to one group is obtained, and the following process is compared with the area of the waveforms belonging to the previously obtained group. do.

That is, when the value of the peak_count is "4", it is checked whether a group (past_area) whose area is previously obtained exists (S171). If the value of the past_area is not "0", the area is previously After determining that the obtained group exists, the area (pre_area) of the previously obtained group is compared with the area (past_area) of the previously obtained group (S172). If larger than), the area difference (area_check) between two groups is obtained (S173), and the area of the group obtained at this time is set in past_area (S174).

On the other hand, if the previously obtained group does not exist, that is, if the value of past_area is "0", the area difference between the groups (area_check) is determined as "0" since the area of the group obtained this time is the area of the first group. (S175), the value of the area of the group obtained at this time is set in past_area (S174).

Thereafter, the area difference between the two groups (area_check) is compared with the variable Delta for the initially set sensitivity (S176), and if the area difference (area_check) between the two groups is larger than the variable Delta, the current filter It is determined that the signal output from the unit 37 is a low frequency signal due to a sudden change in the environment due to the opening and closing of the door (S177), and if the area difference (area_check) between the two groups is smaller than the variable Delta, The door is determined to be a change that appears in the daily environment is not opened (S178).

Finally, if it is determined that the change appears in the daily environment, after initializing the variables such as the area difference (area_check) and the peak_count between the two groups (S179), the process returns to the first step and repeatedly performs. On the other hand, if the door open / close detection device according to the second embodiment of the present invention is configured with a warning signal output unit for outputting a warning signal to the user when the door is opened and closed, the microcontroller 39 controls the warning signal output unit Control to output a warning signal that can be recognized by the user.

As described above, the door open / close detection device and the detection method according to the embodiment of the present invention can more accurately determine the change of the surrounding environment by using the degree of area change according to the change of the frequency or the change of the amplitude of the waveform. When applying such embodiments to the luminaire, it will be possible to implement a luminaire that is automatically turned on / off depending on whether the door is opened or closed. This application is not limited to silk luminaires, and likewise the embodiments described above may also use various changes, modifications, and equivalents.

Therefore, it is clear that the embodiments of the present invention can be applied in the same manner with appropriate modifications, and the above description does not limit the scope of the present invention defined by the limitations of the following claims.

As described above, the door open / close detection device and the detection method of the present invention have the following effects.

By using the output signals of the amplifier, filter unit and offset voltage output unit to determine whether the change of frequency due to the change of the environment is caused by the opening or closing of the door or the noise caused by the daily environment or the circuit configuration. More accurate and accurate discrimination can be made, which effectively eliminates the malfunction of the device and improves the reliability of the device.

In addition, by detecting the amplitude of the waveform according to the change of the surrounding environment and comparing the amplitude of the change of amplitude, it is possible to determine whether the current waveform is due to the opening and closing of the door, it is possible to determine more accurately and precisely.

Claims (18)

A sensor unit for detecting a change in frequency according to a change in the surrounding environment; An amplifier for amplifying an output signal of the sensor unit; A filter unit passing only a frequency of a predetermined band from the output signal of the amplifier; An offset voltage output unit configured to output an offset voltage to the sensor unit, the amplifier unit, and the filter unit; And a microcontroller configured to receive output signals of the amplifying unit, the filter unit, and the offset voltage output unit to determine whether the frequency change sensed by the sensor unit is due to the opening and closing of the door. . The door open / close detection device according to claim 1, further comprising a warning signal output unit selectively outputting a warning signal according to whether the door is opened or closed. The door open / close detection device according to claim 1, wherein the output terminal of the amplifying unit is connected to the input terminal of the filter unit and the microcontroller so that the output signal of the amplifying unit is input to the filter unit and the microcontroller. The door open / close detection device according to claim 1, wherein the filter unit comprises a low pass filter that passes only frequencies of a similar band when the door is opened and closed in the output signal of the amplifier. The door open / close detection device according to claim 1, wherein the microcontroller includes an A / D converter for converting an input analog signal into a digital signal. The apparatus of claim 1, wherein the microcontroller comprises: a first determination unit determining whether a door is opened or closed by measuring a frequency by measuring a time during a half period of a signal waveform output from the filter unit based on the offset voltage; A method for determining whether the door is opened or closed by comparing the signal waveform MS output from the current filter unit with a value MPV positioned below the peak value of the waveform output from the filter unit for a daily environment by a predetermined level. 2 discrimination part, And a third determination unit configured to determine whether the door is opened or closed by comparing the signal waveform VS output from the amplification unit with the waveform output from the filter unit based on an offset voltage. . A sensor unit for detecting a change in frequency according to a change in the surrounding environment; An amplifier for amplifying an output signal of the sensor unit; A filter unit passing only a frequency of a predetermined band from the output signal of the amplifier; An offset voltage output unit configured to output an offset voltage to the sensor unit, the amplifier unit, and the filter unit; A microcontroller configured to determine whether the door is opened or closed through mutual comparison between areas of waveforms located on either side of the waveform output from the filter unit based on the offset voltage; And a sensitivity adjusting unit configured to input the microcontroller by specifying the specific range so as to determine that the door is opened and closed when a difference between the areas exists within a specific range. The method of claim 7, wherein the microcontroller, Door opening and closing detection device, characterized in that for comparing the area between the waveform located below the offset voltage. The method of claim 7, wherein the microcontroller, And grouping a plurality of waveforms among waveforms positioned below the offset voltage based on the offset voltage, and comparing the sum of the sum of the areas of the waveforms included in each group. The door open / close detection device according to claim 7, further comprising a warning signal output unit selectively outputting a warning signal according to whether the door is opened or closed. A first step of detecting a change in frequency according to a change in the surrounding environment; A second step of amplifying the detected signal and filtering only a predetermined bandwidth; And a third step of determining whether the detected signal is due to opening or closing of the door using the amplified signal, the filtered signal, and an offset voltage for amplifying and filtering. 12. The method of claim 11, further comprising: selectively outputting a warning signal in a form recognizable by a user according to whether the door is opened or closed after performing the third step. The method of claim 11, wherein the third step, Determining whether the door is opened or closed by measuring a frequency during a half period of the filtered signal waveform based on the offset voltage, and outputting the filtered signal to the waveform and the daily surroundings of the filtered signal. Determining whether the door is opened or closed by comparing a value (MPV) positioned below the peak value of the waveform by a predetermined level; comparing the waveform of the signal output from the amplifier with the waveform output from the output of the filter; Door opening and closing detection method comprising the step of determining whether the door is opened or closed. The method of claim 13, wherein the calculated frequency is similar to the frequency caused by the opening and closing of the door, and the waveform of the filtered signal is greater than the peak value of the waveform output from the filter unit for the everyday environment. It is determined that the door is opened and closed when the second condition to be positioned below the predetermined level and the third condition that the waveform of the signal output from the amplifier and the waveform output from the filter part are all similar to each other are satisfied. Door opening and closing detection method characterized in that. A first step of detecting a change in frequency according to a change in the surrounding environment; A second step of amplifying the detected signal and filtering only a predetermined bandwidth; And a third step of determining whether the door is opened or closed through mutual comparison between areas having waveforms located on either side of the waveform output from the filter unit based on an offset voltage. . The method of claim 15, wherein the third step, Grouping a plurality of waveforms among waveforms positioned below the offset voltage; Summing the areas of the waveforms belonging to each group, Door opening and closing detection method comprising the step of comparing the summed values. 17. The method of claim 16, wherein the door is determined to be opened and closed when the difference between the summed values is greater than a specific range. 18. The method of claim 17, wherein the designation of the specific range is adjusted according to a voltage value output from the sensitivity adjusting unit.