Design And Implementation Of Multisensor Testing System Based On Virtual Instrument

Sensors,as an important detection device,are widely used in engineering applications.However,the performance detection of sensors can not be accomplished by manual work,and it must be carried out by means of relevant measuring and testing equipment.Sensors are widely used in various environments,which requires the testing and measuring equipment to have strong environmental adaptability to meet the needs of sensor detection in different environments.In order to achieve high-precision measurement of temperature,pressure and digital sensors,a high-precision multi-sensor testing system based on virtual instrument is designed in this paper.The system adopts CPCI bus technology as the standard,and adopts CPCI 8-slot chassis in structure.The structure design has the advantages of portability,anti-seismic,supporting hot swap and so on.It can meet the test and measurement work in different environments.The hardware system chooses PXI-6224 as ADC acquisition board,PXI-8433 as RS422/485 communication board and designs signal conditioning board independently.It can realize high precision performance test of three K-type thermocouples,one B-type thermocouples,one PT100,one PT1000,12-way pressure and 48-way digital pressure sensors.The software uses LabVIEW as the development environment to realize multi-channel signal acquisition,serial data acquisition,data analysis,chart display,storage and other functions.The software provides a good human-computer interaction experience,simple test interface,can achieve one-key test function,and provides the corresponding report printing function according to the needs of users.Firstly,this paper introduces the background of virtual sensor testing and virtualinstrument technology,and introduces the advantages of CPCI technology.Then,starting from the system requirements,according to the analysis of system requirements,the design scheme of the system is determined,and the purpose of high precision,portable and efficient research and development of the system is determined.In the aspect of hardware design,the performance and details of the boad selected by the system are introduced.Parameters,the self-designed signal conditioning circuit is mainly introduced,and the experience in the process of circuit debugging is introduced.In the aspect of software design,the design idea and specific implementation method of the software are elaborated in detail,and the serial port data acquisition,analysis,display and multi-channel data acquisition are introduced in detail.Finally,the test results show that the system can stably achieve high-precision testing of various sensors,the highest test accuracy can reach one-thousandth,and the test results are stable,which can adapt to various test environments and meet the task requirements of the system.