Research And Implementation Of Rotor Load Strain Signal Acquisition System Based On FPGA

The load test of helicopter rotor rotating parts is an important link in the process of helicopter research and development,which is directly related to the service life and system performance of helicopter.In order to obtain the load strength test data of main rotor and tail rotor under flight test conditions,the research and design of rotor load strain signal acquisition system based on FPGA are carried out.The main work of this paper is as follows:1.Analyze the research status of strain signal acquisition system at home and abroad,and introduce the related basic principles of strain signal acquisition technology,which provides theoretical basis for the design of the system;2.A 4-channel strain signal acquisition system with FPGA and HIGH-precision AD as the core is designed to realize high-speed,high-precision and synchronous signal acquisition.Besides,it is equipped with a variety of bridge working mode switching functions,which can meet different applications such as single-arm bridge,half-bridge and full-bridge;3.The Automatic Gain Control Circuit is designed,which can automatically adjust the signal amplitude according to the input signal of the strain bridge,reduce the quantization error of A/D acquisition,and improve the signal acquisition accuracy;4.A fifteenth-order Blackman window FIR linear phase low-pass filter was designed inside the FPGA to effectively filter out the noise and further improve the signal acquisition accuracy;5.The function test of the strain signal acquisition system is completed,and the function of the system design is verified to meet the technical requirements of the system.