The Study On Distributed Optical Fiber Strain Monitoring And Strain Field Reconstruction Method For Typical Mechanical Structure

In the process of the long flight of the aircraft, the damage of the main bearing structure is inevitable because of the bad environment factor, it will go wrong and the task will fail, even though it will cause the significant loss of plane crash. However, the stress and strain information of the key areas are the important basis in evaluating air vehicle health status. Thus it is very important to realize real-time monitoring the stress and strain of the aircraft. Due to the aviation aircraft in different flight conditions show different stress and strain distribution rule, it has to study the high-performance and high reliability characteristics of distributed structural strain monitoring and inversion technique. To provide technology support to observe timely structure strain field distribution information, The main work includes the following aspects:At first, for single-ended clamped beam and slab structure strain field monitoring and inversion, this article studies the layout of the sensors, constructs the strain monitoring system, gives the strain field inversion algorithm.Sets up a single-ended mechanics model of clamped beam and slab structure, observes the single side clamped plate strain field by Numerical simulation, realizes the single-ended clamped beam and slab structure strain field monitoring and inversion. Some experiment is carried on the single-ended clamped aluminum alloy plate. The feasibility of strain monitoring system and the inversion algorithm is verified.Secondly, according to the need of health monitoring when industry pressure vessel is serving, the industrial pressure container shrinkage ratio model is established using CATIA. With the help of ANSYS finite element simulation software to simulate the pressure vessels distribution of strain field under different loading conditions. Using the algorithm based on inverse distance weighting and cubic b-spline functions to realize the strain field of pressure vessel space reconstruction. Using Labview writes industrial pressure container key regional strain online monitoring human-computer interaction interface.Finally, according to the need of monitoring the space fold health in the process of the deployment structure under external load, unfolding the structure of the physical model is established. Using the finite element simulation software to analyze the unfolding process under different external loading, the strain distribution and the position of the dangerous point appeared of the structure. Puts forward the calculation method of distance between any two peaks of the structure in the stretching process. Provide the basis for subsequent axial deformation monitoring. Using Labview to write monitoring interface to monitor the dangerous point of strain and the distance between any two peaks of the structure.