Multiple Fluorescent Liquid Explosives Detection Instrument

In recent years, with the increase in the demand of anti-terrorism, monitoring and management of industrial pollution, non-metallic mine detection, environmental monitoring and many countries are paying more and more attention to the development of high-performance detection instrumentation. Nitro aromatic compounds is not only an important part of the explosives, but the residue of these compounds in the environment pose a serious threat to the survival of humans and animals, thus people attach special importance to the detection of it in underground water, industrial waste water, seawater and the soil as well. Consequently gaseous and liquid nitro aromatic hydrocarbon detection instruments are invented. Altogether research and development of a high performance, Rapid detection and high efficiency of hidden explosives detector has a very important significance in preventing and combating terrorists and criminal activities, detecting and preventing environmental pollution.In this paper, basing on polymer fluorescent film sensor, we design and implement micro-trace explosives detectors with multi-channel, high sensitivity, high-resolution, low-power multi-channel liquid-phase micro-trace explosives detectors. Specific work mainly includes the following aspects:Firstly, we design an efficient signal acquisition system, and use advance diode as a light source, avalanche photo diode is used as a photoelectric conversion device. Besides, the design of a new type of detector cell can improve the fluorescence collection efficiency and the resolution of equipment. The overall debugging the instrument as a whole, achieved the micro-trace explosives detection requirements.Secondly, the instrument design the timing sequence of multi-channel system, the designed time division multiplexing of the control circuit of the multiplex system, with the correlation detecting circuit and the work of the sampled integrator circuit, which are avoid mutual interference in a multi-channel signal, this improve the overall system performance.Thirdly, the weak signal processing techniques and signal recognition technology in the system are specifically implemented in the system, which involves the optical, electronic, mechanical, computer and other technology fusion, which greatly improves the system’s ability to detect weak fluorescence signal. We use an improved classical principal component analysis (PCA) algorithm to classify the explosive substances. Several actual test of the performance of the instrument proves that it has good stability and resolution.The last part is the design of the software system in the detector. The multi-channel detector system includes a test control module, data processing module, the wireless communication module and other functional modules.The experimental results show that the design of the multi-channel detector is have high sensitivity and resolution for a variety of nitro aromatic explosives, thus achieve rapid response, real-time detection of explosives. At the same time, the performance of the instrument can meet the design requirements.