The Design Of The Lighting System In Intelligent College Classroom

According to the characteristics of the classrooms in the universities, in the present article we have designed an intelligent system to control the lights in the classrooms, with which we can effectively avoid to let the lights always on and can also make the classrooms easier to maintain.Before the design, the thesis has made lots of marketing research to analyze the meaning of the research and the actual stat of the domain. Finally, I’ve decided the design plan of the system.The thesis chooses the chip AT89S52as the micro processor of the whole system. Together with other elements as the photosensitive resistances, the change chip AD0804, the infrared sensing signal processer BISS0001and the electric relay, the system can monitor the existence of the human body and the illumination strength, and issue the corresponding orders. To improve the efficiency, using the principal and the subordinate structure, the system is divided into two parts:the upper monitor and the lower monitor, to control the classroom in separate parts. The upper monitor is responsible of the analysis and the comparison of the statistics, and to give relative orders. In order to avoid the rewiring trouble, both the upper and the lower machines use the433MHz radio to transmit the statistics and the orders. In order to better monitor the existence of the human body, some adjustable resistances are used in the infrared pyroelectric circuit, which makes it easier to adjust its sensitivity.The system control process is as follows:first of all, the lower machine checks the presence of the human body in the corresponding part of the classroom. If there is no presence, it continues to detect; if anyone presents, it enters into the interrupt process, and detect the illumination strength in the corresponding part of the classroom and through the AD conversion, converts the light strength into digital information, and then transmit it to the upper monitor by the433MHz radio. After the reception of the statistics, the upper monitor begins the analysis and comparison to make a proper order, which is transmitted back to the lower machine also by the433MHz radio. Finally the lower machine accomplishes the relevant actions.The final test shows that the present article has already accomplished the design of the lighting controlling system of the intelligent classroom, and that the system can function following the way we expected, which, in a certain degree, economic the energy and improves the intelligence level of the lighting system.