The Study Of Multi-point Force Deformation Characteristics Of Aluminum Plate Based On Fiber Bragg Grating

In daily mechanical equipment,many parts will be deformed during use,and some will break and fail when reaching the deformation limit.Bending deformation will bring a lot of harm to mechanical parts and our production and processing.At the same time,it is not conducive to protecting the environment and causing a waste of resources.Therefore,the deformation monitoring of mechanical parts after stress is one of the important conditions for their safe operation.Compared with the disadvantages of large error and large external influence of traditional measurement tools,FBG,as a fiber Bragg grating,has the advantages of small volume,strong anti-interference ability and high sensitivity.It is often used as a sensor for monitoring.Therefore,its application in the monitoring of bending,distortion and deformation of mechanical parts will bring great benefits to production safety.Therefore,FBG is used to study the deformation characteristics of curvature.The research contents of this thesis are as follows:(1)Understand the background and application of fiber grating at home and abroad,analyze the structure,model and principle of fiber grating based on fiber grating,and select suitable fiber grating and sampling materials.(2)ANSYS theoretical modeling is carried out for the sampled aluminum plate.By adding loads at 0,4 and 9 points of the pressure position of the prefabricated plate,the micro displacement platform is lowered by 0.5mm and 7mm respectively at each place,and the simulation calculation is completed to obtain the data of its maximum deformation,stress and strain,including stress nephogram,strain analysis and displacement analysis.It is concluded that the stress will increase with the increase of displacement;The farther away from the measuring point,the smaller the stress.It is verified that the change caused by the falling displacement of 0.05 mm is obvious,which lays a theoretical foundation for the next experiment.(3)Independently set up the experimental system,design the experiment and complete the deformation measurement of different measurement points and different force points of the sampled aluminum plate.Three groups of experiments are designed respectively.One group is the experiment of the change of horizontal orientation with different force points;One group is the experiment of the change of vertical direction with different force points;One group is the experiment of curvature change caused by different arrangement of FBG measurement points.Through these three groups of experiments,we can simulate the different forces on the aluminum mechanical structure in the external environment,get the relationship between the central wavelength of fiber Bragg grating and the amount of deformation decline,then analyze the relationship between deformation and curvature,and finally get the conclusion of the relationship between mechanical deformation and curvature.