上面開口ボックス構造の固有振動特性及び鉛直方向加振を受けた場合のパラメトリック不安定振動に関する研究

抄録

Due to launch restrictions, lightweight structures are often used for space structures. In particular, satellites mounted inside fairings are subjected to severe axial loads during launch, which may lead to the destruction of electronic devices. The purpose of this study is to investigate natural vibration characteristics and parametric instability vibration under vertical excitation of upper-opening box structure. In the present report, we first experimentally clarified natural vibration characteristics by acoustic excitation. The test box used in this experiment was made by joining four sheets of OHP film together with cellophane tape. Three test boxes with aspect ratios (height/width) of λ = 0.5, 1.0, and 2.0 were tested with 1, 2, and 3 pieces of tape at the corners. The acoustic excitation was performed with two speakers exciteing in both in-phase and out-of-phase excitation, and the velocity response of the sides of the test box was measured using a scanning laser Doppler vibrometer to determine the vibration modes and natural frequency of the test box. As a result, the dimensionless natural frequency of the low order modes of upper-opening box structure are close to those of flat plate whose lower edge Clamped and upper edge Free, left and right edge condition Clamped and Clamped at λ = 0.5, Clamped and Simple support at λ = 1.0, and the Simple support and Simple support at λ = 2.0.