Parametric Study on Compression Deformation Behavior of Conformal Load-Bearing Smart Skin Antenna Structure

Abstract

In this paper, a simple conformal load-bearing antenna structure smart skin with a multi-layer sandwich structure composed of carbon/epoxy, glass/epoxy, and a dielectric polymer was designed and fabricated. The mechanical properties of each material in the designed smart skin were obtained from experiments. Tests and analyses were conducted to study the behavior of the smart skin under compressive loads. The designed smart skin failed due to buckling before compression failure. The stresses of each layer and the first failed layer of the smart skin were predicted using MSC/NASTRAN. The finite element model was verified by comparing the numerical results from geometrical linear/nonlinear analyses with the measured data. The numerically predicted structural behavior of the smart skin agreed well with the experimental data. The results showed that the carbon/epoxy layer took charge of most of the compressive load, and the first failure occurred in the dielectric layer while the other layers remained safe. A numerical model was used to obtain design data from the parametric study. The effect of changing the design variables on the buckling and compressive behavior of the smart skin was also investigated. As a result, it was confirmed that the transverse shear moduli of the honeycomb core had a serious impact on the buckling load of the smart skin when the shear deformation was considerable.

Thermal Stability Characteristics and Limit Cycle Oscillation of Smart Skin Structures

“…Until recently, various smart skin models have been investigated in terms of the staking sequences and shapes of dielectric layer [10][11][12][13][14][15][16]. In this work, the skin is modeled as multi-layered sandwich structure as in reference [14].…”

“…You and Hwang [13] also recommended improving antenna performance by material selection and experimental verification. Further, Yoon et al [14] made a structure, and compared with the experiments and numerical results for unidirectional compressed status. Currently, Yoo and Kim [15] investigated optimal design of smart skin structures for thermo-mechanical buckling and vibration using genetic algorithm.…”

Fatigue failure of printed circuit board chemically etched copper traces in multifunctional composite structures

“…In other words, the slope E h in Figure 12 can be assumed to remain linear but reduces as N increases. This results in an increasing strain amplitude Á" (note E h in the denominator of equations (5) and (6)). Paepegem (see equation 1 in that article) by assuming the woven glass ply is a combination of paired unidirectional 0 and 90 plies, each of half lamina thickness…”

“…Despite the host material stiffness degrading with increasing number of cycles N, the analysis presented for computing Á" (equations (5) and (6)) is still applicable based on the assumption that the host material remains linearly elastic (or nearly so) within each single loading cycle. In other words, the slope E h in Figure 12 can be assumed to remain linear but reduces as N increases.…”

“…This study differs from the study of Kim et al 3 in its focus on much narrower copper traces ( 0.25 mm) that have been defined by shadow mask acid etch processing methods common to PCBs. Other studies on the topic of embedded conductors have been related to conformable antenna structures, [4][5][6] structural health monitoring applications 7,8 and smart structures development. [9][10][11] Kim et al 4 have investigated the effect of impacts on embedded antennas and found that distinct threshold energy levels can be established above which impacts will result in antenna system failure.…”