The Design Of ZigBee-based On-line Monitoring System For Dust Concentration And Environmental Parameters

The concentration of dust is an important index for monitoring the quality of air. The dust means solid particles suspended in the air. The dust contaminates working fields and our living space, and can also directly threaten human health, causing in a variety of occupational lung disease. Especially, in the mining, the construction, the manufacturing and other industrial workplace, the dust pollution is a particularly serious factor to human health in a variety of risk effects. What’s more, it may cause an explosion when dust concentration exceeds a certain limit value in high temperature and dry conditions. So temperature and humidity are also important parameters to reflect the environmental comfort.In the traditional system with more lines for monitoring dust, the operator usually uses pocket monitoring equipment, and then enters into the field carrying with the equipment for detecting dust. It not only has a very lower efficiency and more constraints from temperature, humidity and chemicals within the field, but also should collect the data by manual, this is no real-time absolutely. The design of the wireless communication theory in this topic originates from Zig Bee communication technology. The Zig Bee is a wireless network technology which has many advantages, such as like lower power consumption, higher capacity, higher security, lower cost, etc. It is very suitable applied to measuring and controlling for the poorer and dangerous environment. As configured Zig Bee, the system of monitoring dust has no lines, can self-networking automatically, and the monitoring nodes in different positions freely are added or deleted and the monitoring nodes which are lower-power, easier to using and saving the cost of building the system. Thus, Zig Bee is a very suitable technology using to monitoring the concentration of dust.This topic designs new system for monitoring concentration of dust and parameters of environmental through multi-channels based on Zig Bee technology. This system structure is consisted with a Zig Bee network, monitoring nodes and a user central monitoring platform based on a PC. Each monitoring node uses an advanced processor, which as most important component in the controlling system for gathering and processing more information about the dust, the temperature, the humidity and the position of node. According to the principle of light reflection, the dust sensor detecting dust is designed, when some dust particles in the air pass the sensing field,the dust sensor will cause a current by detecting the intensity of the light reflected by these dust.Finally, through applications of technology of multi-channels, the different range of concentration of dust is obtained. This topic design plan adopts SHT10 sensor as the electronic component of detecting temperature and humidity. The temperature and humidity signals can be transferred into digital data by SHT10. This topic also coordinates the clock in each nodes of system applying GPS. LCD displayer and control buttons is designed within each monitoring node, and LCD displayer shows data detected by a variety of sensors, then these data are saved in the monitoring node. According to the instructions from user central monitoring platform, then data from specified node will also be sent back to the computer by Zig Bee network, and will be displayed, analyzed and stored on the monitor of PC. The monitoring software is designed by VB in PC, and mainly functions of this software includes such as sending instructions to the monitoring nodes, receiving the data of detecting concentration of dust, temperature, humidity and position of node sent from monitoring nodes, and then works will be operated as data storied, analyzed and processed. When some parameters leave the set value, the alarm will immediately be sent by the user central monitoring platform. At last, the purpose of monitoring environment on real time can be achieved.The paper also will specially describe the principle of the technology of multi-channels, the circuit and system software are introduced in details. What’s more, we do the function of each module of each monitoring node testing, a whole system testing, communication testing, and user central monitoring platform testing, etc. The results of experimental is shown that the expected function of the subject basically have been achieved by this study. In the future, by improved, this technology monitoring can be applied widely.