Research On Odor Monitoring Platform Based On LabVIEW And CompactRIO

In recent years,with the improvement of China’s environmental monitoring network,there have been more than 5,000 monitoring stations in various provinces and cities across the country.The same is true for odor monitoring,which is an important indicator of environmental monitoring,and it is developing in the direction of regionalized detection and platform management.Aiming at the advantages and disadvantages of common odor detection methods and distributed system monitoring platforms when applied to regional odor monitoring,this thesis proposes a development scheme for odor monitoring platforms and odor gas detection instrument that combines electronic nose technology with virtual instrument software and hardware.According to the scheme,the system architecture of the odor monitoring system was constructed and the software and hardware development of the system was completed,and functions such as software evaluation of the malodor intensity in the area to be measured were realized.The main work of the thesis includes the following aspects:Firstly,make full use of the advantages of virtual instrument software(Lab VIEW)and hardware(Compact RIO)in the development of the monitoring platform,and design a platform that integrates multi-sniffer distributed data acquisition,batch data processing,software deployment and equipment control.Measurement and control scheme and its software and hardware system structure.Secondly,complete the hardware system development of the olfactory instrument and the software development of the monitoring platform.Combining the sensor’s detection principle of odor with Compact RIO’s parallel acquisition control technology,the odor detector is developed to realize the acquisition of odor information.Combining Lab VIEW with a distributed device management tool(System Link)to implement functions such as software batch deployment,distributed data processing,and centralized display.Then,a software evaluation model based on human sensory evaluation is established.In the monitoring platform,qualitative and quantitative analysis of gas is achieved by means of feature dimension reduction and BP neural network.Combining the analysis results with sensory evaluation of human body,a odor intensity level prediction model for mixed gas and regional odor gas is proposed.The model can be based on The qualitative and quantitative analysis results of the gas calculate the malodor intensity level.Finally,the stability and repeatability experiments were performed to verify the ability of the olfactory instrument to collect and output signals.The maximum standard deviation of the output voltage signal of the sensor array of each olfactory instrument was 0.002 V and the maximum relative standard deviation was 1.29%.The maximum relative error in the prediction experiment of the concentration of two elementary gases of methyl sulfide and ethyl acetate and a mixture of the two gases was 4.238%.A software evaluation model was used to predict the overall malodor intensity of the mixed odor and odor regions,and the correlation between the calculated results and the artificial olfactory results was above0.98.The various extended functions designed based on System Link work well in experiments.The accuracy of each test result meets the requirements of the monitoring platform for regional malodor monitoring and sensory evaluation.