The Portable Explosives Detection System

With the rapid development of human civilization has made extraordinary development in all aspects of science and technology, culture, economy, due to the unbalanced development led to many contradictions that the intensification of contradictions, conflicts of ideology is the world’s most serious conflicts, specifically in the terrorist bombing, extremists often use explosives threat to social stability and people’s lives and property. More stricter controls about explosives, and therefore to the Security Ministry of each country special attention, China has also put a lot of researcher and resources to implement research about explosive detection, research institutions hoping to design explosives detection device in real-time response to the increasingly precise prominent security issue. This article is the detailed design of explosives detection systems that has hardware, software and sensor.Thesis consists of three parts, The first section describes the principles that is molecular imprinting technique and production of Molecularly Imprinted piezoelectric sensors detect TNT, HMX, RDX, ammonium nitrate four kinds of explosives. Detailed characteristics of the quality and frequency of the piezoelectric crystal. The second part detailed description based on the principle of molecular imprinting hardware circuit design techniques and detection system of piezoelectric crystals, and the establishment of a piezoelectric sensor circuit model of molecular imprinting laboratory prepared. Including the sensor drive circuit, a signal processing circuit, a microcontroller circuit, alarm circuit, axial fan drive circuit schematic design and manual layout of the PCB. The third most of the detailed description in C language programming microcontroller controls the peripheral drive circuit molecularly imprinted piezoelectric sensor for detecting the output signal, determining the presence of explosives, by the LCD display and LED functional prompt, if the detection of explosives and accompanied by a sound and light alarm.Issue through a lot of experiments, the detection system detects the sensor output signal frequency, sensor performance analysis of explosives identifiable by a large number of experiments can be found after the combination of molecularly imprinted piezoelectric sensors explosive molecules frequency change significantly, verify the sensor spot a sex and specificity. From the experimental data analysis system error control within 0.05811%, which according to their characteristics to determine whether there are explosives.