Design And Simulation Of Temperature Control System Of Portable PCR Instrument

With the development of society and rapidly improvement of medical level, the requirement for disease prevention and detection has been got more attention by people for health. Polymerase Chain Reaction (PCR) is a kind of molecular level of biology technology, producing millions of copies of specific sequences of complex DNA in vitro. The PCR instrument can implement PCR reaction.At present, PCR has been widely used in life science research, clinical diagnosis, forensic identification, biochemical analysis and rapid quarantine and other fields. But PCR technology is still a blank in the field of ship waste water, the design of PCR instrument completed the rapid qualitative detection of pathogens of sewage from ships, reducing the pollution of the marine environment. Unfortunately, the development and research of PCR technology in domestic lags behind abroad for poor foundation of research. So, it has certain theoretical significance and economic value to develop PCR instrument with high precision and low price.The dissertation analyzes temperature requirements and process for the PCR, and design hardware and software system of PCR instrument based on C8051F020. A fuzzy PID optimization model is proposed to improve the temperature precision compared with the traditional PID by simulation. The main contents of the dissertation are as follows:Firstly, the paper introduces the basic principles of PCR and the development in domestic and overseas, and gives detailed analysis for parameters and precision.Secondly, a set of PCR instrument is designed based on C8051F020, and detailed in hardware system, which include power supply model, sensors detection model, controller model. Furthermore, the man-machine interface and detection for hardware is carried out for the stability in operation.Thirdly, the function modules and interfaces are designed according to rules of software modularization, and implements the functions of main routine and four interrupt routines. Then, the program structure and code is optimized to improve operation efficiency and stability.Finally, According to the special requirements of temperature control in PCR technology, the fuzzy PID model is proposed, and verifies the performance by comparing with the traditional PID control in simulations.