Research On Environmental Monitoring System For Ultra-low Temperature Processing

Ultra-low temperature cooling processing is a clean and efficient processing method,which meets the production requirements of green manufacturing.It has the advantages of green environmental protection,improved processing efficiency,and reduced tool wear.As a cooling medium for ultra-low temperature cooling processing,liquid nitrogen can greatly reduce environmental pollution during processing and manufacturing compared with traditional cutting fluids.If a large amount of liquid nitrogen is used in the process,it will inevitably increase the nitrogen concentration in the air.Excessive nitrogen concentration can cause safety risks,but its colorless and odorless characteristics are not easy to be noticed.Therefore,realtime monitoring and early warning of the processing environment during ultra-low temperature processing is critical.In order to realize the monitoring requirements of ultra-low temperature processing environment,this paper studies the environmental monitoring algorithm,and designs and develops the corresponding software and hardware system to realize the real-time monitoring function.For the monitoring of ultra-low temperature processing environment,multi-sensor data fusion technology was selected as the monitoring method,the characteristics of multi-sensor data fusion technology were analyzed,the differences between different algorithms were compared,combined with the actual situation of ultra-low temperature processing environment,DS evidence was selected Theory as the basic framework of the algorithm.The advantages and disadvantages of the DS evidence theory algorithm are analyzed,and the method based on the membership function is adopted to solve the problem that the basic probability assignment function of the evidence theory is difficult to obtain in the application process.The algorithm defects of the DS evidence theory and the information characteristics of the ultra-low temperature processing environment are studied,The weighted fusion method is selected to improve the fusion algorithmThe functional requirements of the environmental monitoring system for ultra-low temperature processing are introduced.The hardware selection and installation scheme of the monitoring system are designed.Based on the LabVIEW development platform,the ultra-low temperature processing environment status monitoring software is developed to meet the functional requirements of ultra-low temperature processing environment status monitoring such as data acquisition,data storage,and intelligent early warning.Three functional modules are designed for data acquisition and display,data storage and reading,and algorithm implementation,which realizes the collection and accumulation of ultra-low temperature processing environmental information.The ultra-low temperature processing environment state monitoring experiment was carried out.The experimental results of the ultra-low temperature processing environment state monitoring algorithm adopted have good feasibility and accuracy,which verified the data collection and real-time display,data storage and reading of the ultra-low temperature processing environment state monitoring software And the function of intelligent early warning to meet the functional requirements of ultra-low temperature processing environmental status monitoring.