Research On Geometyic Accuracy Measurement Of Parabolic Antenna And Its Application

The role of the parabolic antenna is to transmit and receive electromagnetic waves,and their electrical performance depends majorly on its geometric accuracy. It is needto discover an effective means to analyse the surface accuracy.In this thesis, a finite element method and the Dynaform software are firstlyemployed to simulate the whole forming process of parabolic antenna. Afternumerical simulation,a proper processing is planned to form a real parabolic surface.Secondly, its surface shape is measured by a3D coordinate measurement system.Thirdly, an appropriate data pre-processing technique are carried out to re-build the3D model of its inner surface. Finally, the re-built model can be used for the analysisof geometric accuracies and the objective basis of qualified product judgementsduring qualification confirmation step.Data acquisition is an important step of reverse engineering. Typical coordinatedata acquisition methods and their characteristics principle,advantages anddisadvantages are discussed in this thesis. Among them, the structured lightmeasurement PowerScanner-STD is selected for its merits of high accuracy andefficiency. Aiming at requirements of the geometric measurement for a parabolicantenna, a non-contact structured light measurement system is introduced in detailsand employed to obtain its surface data. After that some data pre-processing works arecarried out, such as point cloud registration and integration, noise processing, datasimplification.