Development of bio-aerosols detection control system based on embedded linux

近年来，由于公众对环境大气质量的关注，对大气气溶胶，尤其是大气生物气溶胶的探测技术已经成为当今热点研究领域之一。当气溶胶的浓度达到足够高时，将对人类健康造成威胁。应对上述威胁的首要条件是拥有能够实时、灵敏的检测生物气溶胶浓度的检测技术与仪器。 本文采用以S3C6410芯片为核心处理器的嵌入式硬件平台，以嵌入式linux为操作系统，设计了生物气溶胶监测仪的控制系统。在搭建嵌入式linux开发环境基础上，首先分析了U-Boot的引导流程，修改了相关设置并成功进行了编译和运行。接下来针对本文使用的开发板对linux kernel进行裁剪和移植。最后构建了一个简单的根文件系统。 双通道生物气溶胶监测仪主要包括气溶胶采集单元、仪器定位单元、365nm通道荧光检测系统和280nm通道荧光检测系统。根据芯片手册编写了控制系统中的各个模块程序，根据双通道生物气溶胶的检测步骤完成了嵌入式linux下运动控制程序的开发，研发出了整个生物气溶胶控制系统，实现了相应的功能。 基于光学测量的生物气溶胶检测技术具有快速、无损、灵敏等优点。由于不同种类生物粒子的构成不同，可以利用其本征荧光的不同对一些生物气溶胶的种类进行预判别。本文在原有技术的基础上，研发出了含有280nm和365nm两种激发光波长的双通道生物气溶胶检测系统。利用本检测系统，分别测量了色氨酸、烟酰胺腺嘌呤二核苷酸(NADH)的荧光光谱和强度，确定了对本系统两个通道进行标定的方法，并结合对牛血清蛋白(BSA)以及易引起误判的香烟烟雾等物质的测量结果进行了分析与探讨。实验结果证明了通过多通道紫外光诱导生物气溶胶粒子产生本征荧光，并对荧光光谱与强度等信息进行分析可以实现对粒子的种类较为准确的预判别。In recent years, due to public concern on ambient air quality, atmospheric aerosols, especially atmospheric bio-aerosol detection technology has become one of the hot research fields. When the concentration of the aerosol is high enough, it will pose a threat to human health. Respond to these threats first condition is to have real-time, sensitive detection technology and equipment which can detect the intensity of bio-aerosols. S3C6410 chip core processor is used as the embedded hardware platform, embedded Linux as operating system, and the bio-aerosol detection system’s control system is developed. After setting up embedded development environment, the principle of U-Boot guiding operating system is analysed in detail. Related settings are modified so that it can be able to compile and run successfully. The cutting and transplantation of linux kernel for our board is finished. Finally, a simple root file system is constructed. Dual-channel bio-aerosols monitor includes aerosols acquisition unit, positioning unit, 365 nm and 280 nm fluorescence detection system. According to the chip manual, modules of the control system are developed. According to the detection procedure, the motion control system is completed. Finally, the entire bio-aerosols control system is developed and it can realize the corresponding function. Biological aerosol detection technology based on optical measurement is rapid，non-destructive and sensitive. Due to the configuration of the type of the different types of biological particles, we can use the intrinsic fluorescence to realize aerosols pre-discriminant. Based on the existing technology, the dual-channel bio-aerosol detection method which included 280nm and 365nm channel was developed. With the dual-channel bio-aerosol detection system, the intrinsic fluorescence spectrum and intensity of tryptophan and NADH were detected respectively by deploying the ultraviolet source at 280nm and 365nm. On the basis of the result, the calibration method was determined, and then the analysis of BSA and cigarette particles’ results were researched. The results demonstrate that it can improve the accuracy of particles pre-discrimination by using the dual-channel bio-aerosol detection technology