Design On Environmental Monitoring System For Welding Workshop Based On Zigbee

With the development of the society, higher request for a safe andcomfortable workshop environment is put forward. Therefore, the environmentalparameters monitoring is very important. In this thesis, a welding workshopenvironment monitoring system based on Zigbee is designed for weldingworkshop to avoid the disadvantages of difficult layingout, high failure rate anddifficult maintenance in the cable monitoring system.The welding workshop environment monitoring system designed in thisthesis samples temperature, humidity and eight poisonous and harmful gasconcentrations on real-time in the welding workshop. Zigbee wireless network isdesigned to transmit data on field, and remote monitoring center is accessed viaInternet. The monitoring system is consists of two parts, a field monitoringsystem and a remote monitoring center （PC）.The field monitoring system is consists of wireless data acquisition modulesand a main controller module. The wireless data acquisition module isresponsible for the welding workshop environment data acquisition andtransmission by set up a wireless network spontaneously via a Zigbee technologyproduct, CC2430. SHT11is used to sample temperature and humidity.Electrochemical gas sensors are used to sample four kinds of gas concentrations,carbon monoxide （CO）, hydrogen sulfide （H₂S）, oxygen （O₂） and methane （CH4）.Potential electrolysis gas sensors are used to sample four kinds of gas, sulfurdioxide （SO₂）, formaldehyde （CH₂O）, benzene （C₆H₆） and ammonia （NH₃）. Inthe main controller unit, embedded processor S3C2410with a ARM920T core isused as the microprocessor, a CC2420is extended to set up the Zigbee networkand to receive the sample data, a LCD displayer is extended to displaymonitoring results on field, a CS8900A is set up to access to the Internet.The software of the wireless data acquisition modules and the main controller module are designed in the thesis, including main monitoring program,transplantation of the Linux operating system, the data acquisition subroutine,Zigbee communicating program and Ethernet communicating program, etc.Design ideas and software flow charts are given. The software of remotemonitoring center consists of monitoring interface and monitoring database. Theenvironmental data of the welding workshop thus can be monitored and managedvia the remote PC.