Study Of Multi-Electrochemical Gas Sensor Data Fusion Based On Neural Network

With the development of science and technology,nowadays,many kinds of gases have been applied to industry ? agriculture ? production and life,and occupy a pivotal position.In the process of gases(especially toxic gases)application,it needs to test the composition and concentration of the gases,but a single sensor has the disadvantages of low accuracy and cross interface,this requires to developing a simple and practical gas identification and analysis system to identify the gas composition and also capture the temperature and humidity conditions of the surrounding environment.This multi-gas test system completed the qualitative and quantitative analysis of five toxic gases and established the interference model between the mixed gases,and also studied the multi-sensor data fusion algorithm,solved the problems that cross interference of the multi-gases?low measurement accuracy and poor recognition.In addition,other gases can be identified by changing the type of sensors,so the system has strong commonality.The main researches are as follows:1.Select the appropriate electrochemical gas sensors and temperature and humidity chip according to the natures of toxic gases,and design the power module and front-end sampling circuit of I/U conversion to achieve 0.6 ~ 3V voltage signal output;2.The MSP430F149 microcontroller is used as the core,and completing the hardware and software designing of data acquisition part.Using sensors and temperature and humidity chip to test the concentration of gases and the temperature and humidity of environment,then complete the A / D conversion?PC interface drawing and linear regression analysis of sensors;3.Establish BP neural network to calculate and simulate the signal of data acquisition system.Use Matlab to realize the qualitative and quantitative analysis of the voltage data of the gases,and establish the model of gases crossinterference to provide the basis for improving system performances.At the condition of relatively stable temperature and humidity environment,the concentration testing and cross-interference experiment of five toxic gases are performed.Experiments show that: the system has high sensitivity,good linearity,small measurement error,sets the foundation for demonstrating life support and environmental protection gas monitoring system.