Study On The Key Techniques Of Process Planning Software In Phased Array Testing

A process planning software in phased array testing can simulate the process of inspection,and present the process in a visual manner.To assist the inspector to make the testing plan with the help of this software can save money and time effectively.This thesis determines the functions of a process planning software based on analyzing the existing software in ultrasonic simulation,and then studies the key techniques for implementing these functions.The techniques such as 3D modeling,visualization,coverage detection,acoustic field calculation and signal synthesis are covered in this paper.A constructive solid geometry algorithm based on voxel description is put forward to construct artifacts of complicated shape and multi-media.A translucent rendering method for multi-media artifacts is studied to show the inner structure of these objects.A ray tracing algorithm based on voxel description is used to determine the covered area with the basic scanning mode.The acoustic theory for the computation of probe's radiation field and defect's scattering field are separately studied,and then the signal in time domain of an observation point is obtained through Fourier transformation.A-scan signal is obtained based on focusing principle,and B-scan image is obtained from a series of A-scan signals using bilinear interpolation.A process planning software in phased array called PASIM is designed and developed based on the study of key techniques.This software can work in three modes.They are coverage detection,beam computation and image simulation.Coverage detection determines the scan area using ray model.Beam computation presents the propagation of the beam in the artifacts.Image simulation gives the simulated testing result.A testing case is performed with PASIM and the simulated image is compared with the actual testing image.The result shows that PASIM can simulate the phased array testing effectively.