Indoor Environmental Monitoring And Control System Based On Wireless Sensor Networks

Intelligent building is the combination between construction and computer technology, and it is the information society requirement, as well as the future trend of building development. The design goal of intelligent building is to achieve automation of building integrated management, communication and office, which makes power, lighting and air-condition operate efficiently. The monitoring of air-condition system is the basic requirement of intelligent building automation management and energy saving. However, at present, indoor environmental parameters, such as temperature, humidity etc, is not acquisitioned real time in many buildings, so heating ventilating air conditioning (HVAC) system could not adjust refrigerating or heat capacity and supply air volume, which makes energy waste.With the development of computer technology, sensors, networking and wireless communication, embedded system and control technology, wireless sensor networks has been attention of people. In accordance with problems in air-condition monitoring and control system, based on wireless sensor networks and embedded technology, a real-time indoor environmental monitoring and control system is designed and implemented. Wireless sensor nodes placed in every room are made in a network by self-organized. The temperature and humidity parameters are transmitted to gateway nodes with multi-hop transmission, and then sent to embedded microprocessor by wireless communication network. These data are processed and transferred to central process computer by embedded microprocessor. According to these data, optimization control function is achieved on central process computer. In this thesis, the system hardware and software structure are designed based on requirement analysis, hardware selection and software programming are completed. Qt is used as interface development environment on Linux. Combining with SQLite, indoor environmental monitoring and control system is implemented using C++ programming language.By testing, some functions are accomplished. For example, refrigerating or heat capacity of air-condition is computed, and supply air volume is adjusted. Meanwhile, cost is calculated according to energy consumption of users. This system can improve the level of energy utilization and achieve the saving energy goal under the condition of comfort requirement is needed.