極超音速気流中における形状記憶合金製フレームを有する柔構造体エアロシェルの展開実験

摘要

For re-entry missions, deployable-flexible aeroshell is expected to have an advantage because it can significantly reduce the aerodynamic heating due to deceleration at relatively high altitudes thanks to its small mass and large area (i.e. low ballistic coefficient), while it can be stowed compactly during the launch phase. In this study, we propose deployable aeroshell supported by the shape memory alloy frame, which can deploy itself automatically by receiving the aerodynamic heating. The present system neither requires additional sensors nor acuators. It seems suitable for small re-entry capsule because of its simple, fault-tolerant and low-cost nature. It is experimentally demonstrated by the wind tunnel tests that a model having a membrane aeroshell with a shape memory alloy frame is smoothly deployed and kept stable in hypersonic flow.%形状記憶合金製のフレームを有する柔構造飛翔体のモデルを作成し，極超音速気流中において同柔構造体の展開実証試験を行った．飛翔体のモデルは極超音速気流中に投入後5秒程度をかけて展開し，その展開に応じて衝撃波の形状の変化や抵抗係数の増加が確認された．