Volume 3 Issue 1
Authors: Yundong Zhu; Xin Yang; Jiaojiao Ren; Lijuan Li
Abstract: A digitized measurement method was detailed for nozzle thrust line of solid rocket motor based on advanced non-contact measuring technology with laser radar. The principle of this measurement method and the self-calibration technology of tolling ball are deeply researched. It proposes a new measuring scheme for thrust line which aiming at the front and back face circularity, circular zero line and the inner 3-D shape of the motor nozzle. The thrust line is obtained through the proper optimization model, and experiment testing shows that this measurement method provides higher measuring precision and efficiency which ensure the accuracy of thrust line direction.
Keywords: Nozzle thrust line; Digitized measurement; Laser Radar
Authors: Abdallah Hamed
Abstract: In this paper, apertures in the form of graded index distribution and truncated apertures are investigated. The 1st type of graded index aperture has central black zone followed by steps with increased intensity directed outwards. The second aperture has successive black and transparent annuls with central opaque zone. The third has four different truncated apertures. Digital diffuser is fabricated to get modulated speckle images for all described apertures. The profile of the speckle images and the corresponding autocorrelation profiles are plotted and the speckle sizes are computed for the different cited apertures. A Mat-lab code is written to compute and plot all of the above images.
Keywords: Graded Index Apertures; Speckle Images; Numerical Image Processing