Research On Computer Aided Strength Test System

Aircraft Strength test is one of the most important parts in aircraft design,it resolving if the plane can fall into a pattern and be in service. It being thinks highly in the world and in our County. However,it has some problems in aircraft strength test in our County. These include the backward of test preparing work styles,the lack of data tracking and analyzing in test process,insufficient of data processing after test,and the weakness in management of test engineering data. All these restricting the improving of test quality and the overall level of aircraft design.Taking the strength test in the core,Computer Aided Strength Test System (CASTS) compost techniques of test engineering,software engineering,CAD and Computer Graphics,and trying to make a computer aided software system of integrated,opened and visually,to improving the efficiency and quality of test.This thesis describes some essential points in the development of CASTS,including:1) The methodology of developing CASTS had discussed,involving life cycle model suit for CASTS,object oriented analyzing and designing methods.2) A 3-step model had been developed for CASTS life cycle issue,this model has the ability of global control and planning for the software developing,and ensures that the work can be done in good quality and accomplished in time.3) The UML (Unified Modeling Language) had been introduced into CASTS,and made it the main tools of analyzing and designing through the whole developing life cycles.4) Using UML to specify,visualize,document the artifacts of the CASTS,and set up the framework of CASTS.5) Load processing is one important work in test preparing. The progress and method of load processing are discussed in this thesis. An optimizing process method has raised which divided the process of load processing into four sub-processes,i.e. depart load region,calculate typical load distribution,global equilibrating and assess errors. This optimizing method had been used successfully in full-scale aircraft testing.6) In the global equilibrating,a modified Lagrange multiplier method had bring forward. This method can solve inequality constrained optimizer problems. The method is easy to use andfast calculation.7) The AAS (Average-Approximation Subdivision) scheme had risen in this thesis. This scheme solved the problem of constructing three-dimension surface of distributing load continuously and smoothly from scattered point load.8) The AAS scheme has the property of maintaining the mechanical equation,smoothness controllable,has lifting scheme and easy,fast calculation.9) In the processing of correlation visualization,the Voronoi diagram and the Delaunay triangulation had been introduced for the first time,and use them as the bases of defining the topology of the scattered load points,calculating the correlation and filling the color.10) Establishing the Test Engineering Database Management System (TEDBMS),collecting and sharing information is the base of developing CASTS. Tow key problems had been solved in the approaching of TEDBMS;they are hierarchical table storage and class futures storage.11) For the first time,the Digital Pre-Assembly (DPA) had been introduced into the test design stage of aircraft strength testing. Combine with the techniques of 3D modeling and complex sense visualization,accomplished the test equipment and test spectrum modeling,digital pre-assembly of test plan,and completed test simulation primitively.