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The satellite structural mass is considered a crucial parameter during the process of satellite structural design. Sandwich structures acquire a considerable role in minimizing such mass while maintaining structural integrity. This article discusses the structural configuration, design, and analysis of a small satellite. A small Earth remote sensing satellite is chosen from the published data as a case study. Its structural design configuration is of a rectangular box that is based upon metallic alloys. Through a comprehensive study, the most suitable design configuration for the given mission is selected. A contribution has been made in developing a novel hexagonal primary structure that is based upon Aluminum honeycomb sandwich panels. The satellite configuration process and structural design procedure are thoroughly presented. The finite element modeling of honeycomb sandwich panels according to sandwich theory is introduced. Such modeling is validated numerically in comparison with published data. The analysis process is implemented using finite element analysis considering the loads during the ground and launch phases. The proposed structural design results in a significant mass reduction of 15% when compared with the baseline case study.

In the present work, a modified higher-order shear deformation theory is developed to analyze isotropic and composite plates to obtain the static response as well as dynamic characteristics using Ritz solution technique. The displacement-field equations of Lo's higher order shear deformation theory are modified by representing the total rotation of the normal to the mid-plane by two components, bending and shear rotations. The model is valid for thin and thick plates. The plates are subjected to mechanical loads with different types of boundary conditions. A Mathematica code is developed to analyze different plate problems. The obtained results are compared to the available studies solved by different theories and finite element methods. It is shown that the obtained results are accurate using less number of degrees of freedom.

SYNOPSISThe ultrasonic pulse-echo technique and differential thermal analysis were utilized to characterize and to monitor the effect of y-irradiation on the sonic modulus and the heat effect of low-density polyethylene. The sonic wave velocity, sonic modulus, and specific gravity exhibit a minimum for samples irradiated at 10 Mrad. A minimum in the heat capacity was observed at 1 Mrad. The estimated relative change of the activation energy of ordering exhibits a minimum at 100 Mrad. Below 10 Mrad, the perturbation and the loss of the crystalline phase override the effect of radiation cross-linking. From 10 to 100 Mrad, the effect of cross-linking as well as that of crystallinity are prevailing. Oxidative degradation is dominating above 100 Mrad. 0 1993 John Wiley & Sons, Inc.

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