本研究旨在探討獨角仙鞘翅與後翅之間的流場交互作用，並評估不同鞘翅振幅與拍翅範圍對後翅氣動力表現之影響。為建立完整的氣動交互理解，實驗分為三個階段進行：動作分析、力量測試與PIV流場觀測。首先，透過動作追蹤技術與向量內積計算，驗證所設計仿生拍撲機構與實際獨角仙懸停飛行行為之相符性，三自由度運動軌跡相關係數皆高於0.99。接續使用六軸力感測器Mini40，量測拍撲過程中鞘翅與後翅所產生之升力與阻力；最後藉由粒子影像測速法(PIV)，觀測拍撲關鍵時刻之渦流結構。
實驗結果顯示，鞘翅以振幅30度拍撲時可適度抑制後翅翼前緣渦流達成降低誘導阻力並維持升力輸出之氣動優勢，有效提升後翅整體升阻比；反之，當振幅增加則可能導致壓力阻力增加，同時過度抑制後翅之翼前緣渦流，導致氣動效率下降，並且振幅50度之實驗組展現最低之升阻比。此外，鞘翅拍翅範圍亦會影響後翅氣動表現，當其接近後翅最大升力區(32度~22度)，對前緣渦的抑制效果最為顯著，且鞘翅拍撲範圍10度~40度實驗阻展現最高升阻比，40度~70度組為最低。
研究顯示若欲透過鞘翅提升後翅氣動效能，需同時考量其振幅與拍撲時機之配置，促使其渦流生成時序與空間分布與後翅達成良好匹配。本研究不僅揭示多翼系統間之渦流交互機制，亦為未來仿生飛行器設計與控制策略提供理論依據與實驗基礎。

This study investigates the aerodynamic interactions between the elytra and hindwings of the rhinoceros beetle, focusing on how different flapping amplitudes and ranges of the elytra affect hindwing performance. Experiments were conducted in three stages: kinematic analysis, force measurement, and PIV (Particle Image Velocimetry) flow field observation.
Motion tracking and vector inner product calculations confirmed the biomimetic flapping mechanism closely replicated beetle hovering, with correlation coefficients for all three degrees of freedom exceeding 0.99. A six-axis force sensor (Mini40) measured lift and drag generated by the elytra and hindwings, while PIV captured vortex structures at critical flapping moments.
Results show that a 30° elytra amplitude moderately suppresses the hindwing’s leading-edge vortex (LEV), reducing induced drag while maintaining lift and improving the lift-to-drag ratio. Larger amplitudes increase pressure drag and over-suppress the LEV, lowering efficiency; the 50° group showed the lowest lift-to-drag ratio.
Flapping range also affects performance. When aligned with the hindwing’s maximum lift phase (32°–22°), LEV suppression is strongest. The 10°–40° range achieved the highest lift-to-drag ratio, while the 40°–70° range performed worst.
Overall, optimizing both amplitude and timing of elytra flapping can enhance hindwing efficiency by aligning vortex formation with wing motion. These findings clarify vortex interaction mechanisms in multi-wing systems and offer design insights for bio-inspired flying robots.

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