A ZigBee-based System For Environment Monitoring And Energy Saving Control In Hull Workshop

In the shipbuilding process, lighting system in hull workshop consumes a large amount of electricity and the temperature and humidity inside affect the safety and quality of production directly. In order to save energy and monitor the temperature and humidity of working space in real time, an environment monitoring and energy saving control system was designed based on ZigBee wireless sensor networks. By locating workers’ coordinates, the corresponding lighting devices are on-off automatically. The temperature and humidity are adjusted automatically by analyzing and processing the real-time temperature and humidity data sent from monitoring nodes. The test results in hull workshop show that the average location error is less than 1.2m and the energy saving is also effective.ZigBee could be embedded in all kinds of devices, support in-door Geo-location function, achieve precise positioning of a moving target and high quality wireless transmission of data in real time. And it is used widely in area of industrial monitoring, safety system, smart home, etc. The work was done as follows:(1) The functions of establishing of wireless network and data transmitting are programmed in the APS and HAL layer of Z-Stack. Besides optimization location algorithm and retransmission mechanism are designed to improve location accuracy and ensure the exactitude of data transmitting.(2) The software with expanded functions is developed through TI Z-Location Engine. It is used to analyze and proceed the real-time data monitored by hardware devices to drive relays to work and display the number of workers in each area.(3) Control Module consists of STC89C52 MCU development board with two serial ports and relay switch board integrated 16 ones. Loads switch information compiled by software is transmitted to MCU by serial line. And then Relay Board gets control messages compiled by MCU based on the communication protocol between MCU and Relay Board and sent by serial line to take switching action.It can implement that only in specific places of working with workers the lighting devices turn on. And it keeps temperature and humidity values in appropriate level automatically. In this way the goals of energy-saving, intelligent control and safe production can be achieved.