Research On Distributed Optical Fiber Intelligent Monitoring Technology Of Helicopter Rotor Blade Bending Moment And Deformation

Helicopter rotating blades are the main components of helicopter engine function conversion.With the deepening of research,helicopters continue to develop toward high speed,high load and high reliability,which is bound to greatly improve their mechanical performance.As the main bearing component,the blade's structural health is closely related to its load,bending deformation and vibration.Therefore,based on distributed optical fiber sensing technology,this paper studies the bending moment and deformation monitoring methods of helicopter rotor blade structure,and provides a basis for evaluating blade design and mechanical fault diagnosis and prediction.The work mainly includes the following aspects:Firstly,the finite element method is used to simulate the various parameters of the blade service state of the blade,such as the blade bending moment,the pendulum bending moment and the blade bending deformation,and the mechanical properties of the blade structure under different load conditions are obtained.Provide a basis for the distributed fiber optic sensing network layout of the rotating blade structure.Secondly,the multi-parameter monitoring method of helicopter rotor blade structure based on distributed optical fiber sensor is studied.According to the structure and bearing characteristics of the blade,the method of monitoring and calculating the flapping moment of the carbon fiber composite blade structure and the two-dimensional deformation inversion algorithm are explored,and the feasibility of the method is verified by inversion.Thirdly,a multi-parameter distributed optical fiber dynamic monitoring hardware test system for helicopter rotor blades is constructed.Based on carbon fiber composite blade,stepping motor and fiber optic slip ring,the dynamic monitoring test platform of rotating blade was designed and fabricated.A layout type and optimization of surface-mount distributed optical fiber sensor network for helicopter blade structure was proposed.method.Then,based on the imaging software LabVIEW,the interactive platform of helicopter blade bending moment and deformation dynamic monitoring software was written.According to the system function requirements,the framework design of the multi-parameter dynamic monitoring software for the blade is completed,involving multiple modules such as data acquisition,data processing and data display,and the system program is written and the design and optimization of the human-computer interaction interface is completed.Finally,the experimental and functional verification of the distributed optical fiber integrated monitoring system for helicopter rotor blade bending moment and deformation is carried out.On-line integrated monitoring of various parameters such as helicopter rotor blade waving moment,pendulum bending moment,blade bending deformation deflection and so on is realized.On this basis,the formation mechanism and evaluation method of bending moment and deformation monitoring inversion error are given.