Design Of Data Acquisition And Servo Loading System Based On Virtual Instrument

With the development of the aerospace industry,more large-scale aerospace componentshave been manufactured.Aerospace components need mechanical tests and data collected during the research and development phase verify their mechanical properties.With the help of virtual instrument technology,it is possible to flexibly customize the test scheme,achieve multiple forms of mechanical loading,and collect high-accuracy test data.In this paper,with the help of the National Instruments hardware,multi-channel strain acquisition system and the hydraulic servo mechanics loading system are designed based on the virtual instrument technology and tested.The main research content of this paper is as follows:(1)introduced the virtual instrument technology.First introduce the characteristics of the Lab VIEW programming language,compare with traditional instruments showing the advantages of the virtual instrument to quickly build a test platform.The second is to study the use of NI's configuration management software Max and data acquisition assistant DAQ to achieve analog signal acquisition.Finally,the real-time system implementation of Lab VIEW is studied.(2)Designed a multi-channel strain acquisition system.Taking the PXIe1085 chassis and PXIe4330 acquisition card as the hardware structure of the acquisition system,using the "producer-consumer" model to design the software architecture,using the queue and notification synchronization data transfer structure,we achieve a single point of acquisition,timing acquisition,continuous acquisition of three modes.The test data supports TDMS format for high-speed storage and data playback.Finally,a 120 ohm fixed value resistor is used for testing.The system is stable and meets the requirements.(3)A hydraulic servo loading system was designed.Firstly,the working principle of the servo system and the hardware structure required by the system are introduced,and the hardware platform is designed.In addition,comparing the effects of two different PID controllers,the incremental PID controller was selected.And the “producer-consumer”combined with Lab VIEW multi-thread programming technology and RT real-time technology was used to design the software platform.Finally,we realized the real-time system test for displacement loading,cyclic loading,and hierarchical loading.The system meets the real-time requirements and proves that the solution is feasible.