KR20030018687A - Intelligent human body detection system for unmanned remote supervisory system - Google Patents

Abstract

PURPOSE: An intelligent body sensor for an unmanned remote monitoring system is provided to sense and analyze a body by means of discrete digital information and manually and automatically control an alarm function at a long distance. CONSTITUTION: A superconducting infrared ray sensor(2) receives and converts a signal condensed by a Fresnel lens(1) into an electric signal. An amplifier(3) amplifies a signal from the superconducting infrared ray sensor(2). A band pass filter(4) passes a frequency component in consideration of a motion of a body. A micro controller(6) receives the signal from the band pass filter(4) as an input of an analog/digital(A/D) converter(5) and performs an A/D conversion every sample period, and senses and analyzes the body. An RS-485 communication drive circuit(10) is used to access an unmanned monitoring system. A key input section(9) sets an allotted self address. A display circuit(8) displays body sensing information and the set address.

Description

Intelligent human body detection system for unmanned remote supervisory system

The present invention relates to a human body detection device used in security systems, industrial accident prevention systems, and more, more specifically, the remote monitoring that can remotely transmit a variety of information extracted from the detection signal, compared to the existing system only outputs a simple analog alarm signal It's about the system.

In general, in the case of a private office or a vinyl house of a facility cultivation complex, which is not secured, an alarm device is used to prevent outside intrusion, and a detector using a pyroelectric infrared sensor (PIR sensor) is often used. The pyroelectric infrared sensor, which is widely used as a human body sensor, uses a pyroelectric as a sensing element, and generates a signal by detecting infrared rays of 9 to 10 μm emitted by the human body. A pyroelectric sensor is a sensor using the pyroelectric effect of a ferroelectric with high insulation resistance. When the infrared is irradiated to the pyroelectric, and a sensitive temperature change occurs, the spontaneous polarization of the ferroelectric changes and the pyroelectric current flows on the surface. FETs with high FETs are used, and 5-7 μm cut-on filters are used as window materials to reduce interference from sunlight and other external heat sources.

The existing sensor detector using the amplifier uses an amplifier with a bandpass filter in consideration of the human body movement to amplify the weak signal from the sensor.The two stages are used to maintain the required amplification degree (typically 60 to 80 dB). In this case, in order to amplify only the signal corresponding to the response period of the sensor, the band pass frequency is designed to be about 0.2 to several tens Hz. When the output signal of the amplifier is larger than the reference voltage set in the comparator, the amplifier is configured to operate a driving circuit such as an alarm for a set time in the timer circuit. In addition, the sensor alone can detect only objects within 1m, and the viewing angle is narrow, so that the volumetric fresnel lens or horizontal curtain fresnel lens is used to condense the radiant energy from the human body to increase the detection distance up to ten meters and wide the viewing angle. .

However, existing systems are vulnerable to changes in the surrounding environment such as temperature changes and malfunctions, or they cannot be recognized when the signal is smaller than the reference voltage of the comparator. When the reference voltage is lowered, it is not free from the effects of noise or wind. Even if it is applied to an unmanned surveillance system, it is only possible to transmit only the ON and OFF signals according to the presence or absence of a human body, so there is a possibility that the situation of the site cannot be properly transmitted.

The present invention is to solve the above problems by connecting the output of the amplifier to the A / D module built in the microcontroller by analyzing and determining whether the human body is detected by the digital information converted into discrete values, various simple rather than simple ON, OFF signal By sending analysis information to make more accurate situation judgment, it is possible to clarify the detection signal and human body detection signal by the change of surrounding environment or animal, and also to control the alarm function automatically and manually from the remote location, so that it does not malfunction for the authorized user. Its purpose is to avoid that.

1 is a block diagram showing the overall configuration of the intelligent human detection device for an unmanned remote monitoring system according to the present invention

2 is an energy signal (input signal) and an output signal amplified by a sensor radiated from a monitoring object (human and animal) located at the same distance according to the present invention.

* Explanation of symbols for main parts of the drawings

1: Fresnel lens 2: Infrared sensor

3: Amplifier 4: Bandpass Filter

5: A / D conversion module 6: microcontroller

7: output drive circuit 8: display circuit

9: KEY10: communication drive circuit

11: Signal of energy radiated from the human body

12: human body detection signal amplified by infrared sensor

13: Signal of energy radiated from animals

14: Animal detection signal amplified by the infrared sensor

1 is a block diagram showing the configuration of the present invention for achieving the above object. A dual element type pyroelectric infrared sensor (2) using a fresnel lens (1) for condensing and a 5 µm cut-on filter as a window, a two-stage amplifier (3) for amplifying a signal, and a band pass considering the human body movement Filter 4 was used. The amplification degree is about 80dB at 1Hz and the bandpass frequency is designed to be 0.4 ~ 8Hz. The amplified signal through the filter is connected to the A / D input port of the microcontroller 6 with the built-in A / D conversion module 5 with 10-bit resolution, and is converted into discrete values every sampling period to store information. do. At this time, the peak value and the period of the signal are calculated by analyzing the read information, and based on this, the accurate human detection signal can be detected by comparing and analyzing the signal data of various preset cases. Figure 2 shows the radiation energy signal (input signal) of the human body and the animal in the same position and the output signal amplified by the infrared sensor. In case of fast detection of the animal, the bandpass filter is filtered to some extent. However, if the distance is far from the sensor, the signal can be detected due to the increased detection range of each fresnel lens (1). The peak value Vpb of the signal waveform 14 has a smaller value than that of the human body, and if the human body has a relatively large heating volume, the peak value Vpa of the large signal waveform 12 is naturally obtained even at the same distance. In addition, the difference between the operating speed of the human and the animal is shown as a difference in frequency, and the radiant energy detected from the movement of the animal is represented by a rapid signal increase rate, so that the increase rate of the animal detection signal 14 is greater than the increase rate Vpa / ta of the human body detection signal 12. Vpb / tb is large, and the period Tb of the energy signal 13 emitted from the animal is shorter than the period Ta of the energy signal 11 emitted from the human body. The human body and the animal can be distinguished by making and storing a lookup table and comparing the detected frequencies. In the case of the human body can also find out the approximate distance. The detected information is transmitted to the main device (a device that collects and sends various sensing information to a subscriber) of the unmanned surveillance system through the communication drive circuit 10 using the RS-485 communication method, and is allocated to each sensing device. It communicates by receiving the address. In addition, the address and detection information of the human body detection device and whether the detection is displayed on the display circuit (FND and LED) (8), the user can control the alarm device automatically and manually by receiving information controlled remotely. And when constructing network with several sensing modules, it is equipped with 4 keys (9) for inputting address assigned to each module and setting and releasing alarm function by itself, and it is possible to maintain the setting status in case of power failure. Back-up to the built-in EEPROM.

As described above, according to the present invention, the analog signal of the sensor is converted into digital information using a microcontroller and analyzed, so that accurate and reliable detection performance can be realized using only software without additional hardware, and alarm function is provided by remote control. Can be set and released, so it can be used at low cost in various fields that need human body detection such as security system, industrial accident prevention system and various home appliances system.

Claims (2)

In a human body sensing device and similar system that detects and amplifies an infrared signal of a human body using a pyroelectric infrared sensor and generates an alarm signal and connects the signal to an unmanned surveillance system, A pyroelectric infrared sensor (2) for receiving an signal collected by a Fresnel lens (1) for collecting infrared rays emitted from a surface of a person or an animal, and generating an electrical signal; An amplifier 3 for amplifying the signal of the pyroelectric infrared sensor 2, a band pass filter 4 for passing only a frequency component in consideration of the movement of the human body; The signal passed through the amplifier (3) and the bandpass filter (4) is received as an input of the A / D conversion module (5) built in the microcontroller (6), and A / D conversion is performed for each sampling period to obtain this information. A microcontroller 6 having a function of analyzing, determining, and outputting whether human body is detected by using; RS-485 communication drive circuit 10 for connecting to unmanned surveillance system, KEY (9) input for setting its own address and setting and releasing alarm function itself, and human body sensing information and set address. A human body sensing device comprising a display circuit (8) consisting of an FND and an LED for displaying. The method of claim 1, In order to distinguish the response signal of the sensor from the moving animal or other surrounding environment and the human body detection signal, the peak value of the human body detection signal is moved to the lookup table at a certain distance by utilizing the difference in the frequency of the movement between the human body and other objects. Create and store and compare the detected frequencies to distinguish the human body from other objects, and in the case of the human body, input judgment logic to find out the approximate distance from the sensor to the microcontroller and back-up important information. Human body detection device characterized in that it holds.