| Summary: | 碩士 === 國立成功大學 === 航空太空工程學系碩博士班 === 95 === This research is designed to study the impulsive environment construction for military advanced electronic and/or pyrotechnic equipments testing using a drop tower tester. The special cylindrical conical tip-ended soft target samples were struck by a rigid and heavy rigid steel platform. This work numerically studied the dynamic impact response of the top surface of the platform, and the simulated terminal peak saw-tooth pulse waveform was reported. The LS-DYNA transient explicit FEM code was used to perform the numerical simulations. The isotropic bilinear work hardening constitutive law was applied to the softer target programmer. thirty-five simulated results were reported and the target samples weighing 50 to 1,400 gm were characterized to be seven types. The 12. 6 kg, 28.4 kg and 113.6 kg drop tables were used to perform the numerical drop impact tests, the acceleration wave of the top surface of the rigid tables were carefully reported and discussed. Reasonable good results were presented. Finally joins the Back-Propagation Artificial Neural Network the theory, and coordinates LS-DYNA in view of to simulate the value broach of special cylindrical conical tip-ended soft target test samples by the different drop tables drift impact speed impact different size outlook, does for the but actually transmission class nerve network training and the study information bank, achieved can beforehand aim at broach of column test sample the different drop hammer impact speed impact different size outlook, after has the acceleration the reason saw-tooth shock wave the maximum acceleration value (Peak Acceleration) with the impact pulse wave time (Pulse Duration), makes the forecast and the appraisal helps the determination to simulate and to test needs the impact condition parameter, And the reduction simulates the time and the cost which and tests must consume.
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