本研究以綠繡眼為研究對象，參考其等速前飛之動作，並製作四自由度仿生拍撲機構，於風洞及真空艙中模擬其飛行動作，並量測垂直力變化，探討內翼的動作變化對於垂直力的影響，期望可做為微型拍撲飛行器的翼型設計參考。本實驗參考前人生物觀察之結果，以具有四個自由度的仿生拍撲機構模擬綠繡眼等速前飛運動過程中的動作變化，以拍撲動作所產生的垂直力變化來探討肩-腕關節距離在不同風速下之氣動力效應。實驗分為兩組，分別為動作模式一為具有肩-腕關節距離變化的綠繡眼前飛運動，以及模式二的固定內翼且其他拍撲角度仍模擬綠繡眼之動作。實驗結果在來流速度較低時，動作模式二有較佳的垂直力表現，但動作模式一卻有較好的飛行穩定性；而在較高的來流速度時，動作模式一則為最佳的選擇，因此，在微型拍撲飛行器的設計上，可根據飛行條件以及策略作翼型設計；在較低的飛行速度且需要較佳的垂直力表現，則可以選擇動作模式二，不需設計可調式內翼，但如果需要較佳的飛行穩定性，則可以將內翼變化納入考量；在較高的飛行速度下，動作模式一為最佳的拍撲動作，可提供較好的垂直力表現，同時有不錯的飛行穩定性。在未來拍撲微飛行器的設計上，可參考本論文可調節式內翼的兩段式飛翼設計，並針對不同飛行任務之飛行條件選擇飛行模式，增進拍撲微飛行器之飛行表現。

The aim of this study is to design and fabricate a multiarticulate flapping-wing robot with four degrees of freedom in order to imitate forward flying motion of passerines for force measurement in low-speed wind tunnel. To investigate the aerodynamic effects of inner wing change of passerines in forward flight, the previous work which observed the wing kinematics of passerines was utilized to obtain wing trajectories. Tow modified motion cases were experimented in this study, one with the cyclic change in inner wing area, resemble the real passerines, and one with the fixed inner wing area. Two cameras were utilized to completely record kinematic of robot and verify the wing trajectories by direct linear transformation (DLT), which is sure that the motion of the robot has high correlation with the desired trajectories. The experiments were executed not only in wind tunnel with wind velocity at 3 m/s and 5 m/s but also in vacuum chamber to subtract inertial part from wind tunnel results so as to observe the aerodynamic difference between two cases. The force measurement results can be split into three phases in a wingbeat cycle and show that changing the inner wing area truly has certain degree of impact on three-dimension flow field structure especially in upstroke period. In phase two, lateral motion to decrease the wing area do inhibit the negative perpendicular force. However, this lateral motion has an impact on leading edge vortex (LEV) and some complicate wing-wake interaction. With the wind speed increase, aerodynamic effect of lateral motion has less impact on phase tow so that decreasing the wing area can better reduce the negative perpendicular force. On this basis, we can provide a wing design and fly motion idea to MAV design and PIV experiment should be done in the future to get thoroughly understand on aerodynamic mechanism during forward flight of passerines.

[1] D. A. Reay, The history of man-powered flight. Elsevier, 2014.
[2] T. A. Ward, C. J. Fearday, E. Salami, and N. Binti Soin, "A bibliometric review of progress in micro air vehicle research," International Journal of Micro Air Vehicles, vol. 9, no. 2, pp. 146-165, 2017.
[3] R. J. Wood et al., "An autonomous palm-sized gliding micro air vehicle," IEEE Robotics & Automation Magazine, vol. 14, no. 2, pp. 82-91, 2007.
[4] F. Bohorquez, P. Samuel, J. Sirohi, D. Pines, L. Rudd, and R. Perel, "Design, analysis and hover performance of a rotary wing micro air vehicle," Journal of the American Helicopter Society, vol. 48, no. 2, pp. 80-90, 2003.
[5] S. Deng, M. Percin, and B. van Oudheusden, "Experimental investigation of aerodynamics of flapping-wing micro-air-vehicle by force and flow-field measurements," AIAA Journal, vol. 54, no. 2, pp. 588-602, 2016.
[6] D. Lentink and M. H. Dickinson, "Rotational accelerations stabilize leading edge vortices on revolving fly wings," Journal of Experimental Biology, vol. 212, no. 16, pp. 2705-2719, 2009.
[7] J. Song, H. Luo, B. Tobalske, and T. Hedrick, "Three-dimensional numerical simulation of hummingbird forward flight," in 46th AIAA Fluid Dynamics Conference, 2016, p. 3253.
[8] J.-Y. Su, S.-C. Ting, Y.-H. Chang, and J.-T. Yang, "A passerine spreads its tail to facilitate a rapid recovery of its body posture during hovering," Journal of the Royal Society Interface, vol. 9, no. 72, pp. 1674-1684, 2012.
[9] A. Azuma, The biokinetics of flying and swimming. American Institute of Aeronautics and Astronautics, 2006.
[10] N. Phillips, K. Knowles, and R. J. Bomphrey, "The effect of aspect ratio on the leading-edge vortex over an insect-like flapping wing," Bioinspiration & biomimetics, vol. 10, no. 5, p. 056020, 2015.
[11] 黃佩儀, "綠繡眼飛行模式分析與仿鳥拍撲機構之設計," 碩士論文, 國立台灣大學機械工程研究所, 2015.
[12] W. Shyy, H. Aono, C.-k. Kang, and H. Liu, An introduction to flapping wing aerodynamics. Cambridge University Press, 2013.
[13] H. Babinsky, "How do wings work?," Physics Education, vol. 38, no. 6, p. 497, 2003.
[14] X. X. Wang and Z. N. Wu, "Stroke-averaged lift forces due to vortex rings and their mutual interactions for a flapping flight model," Journal of Fluid Mechanics, vol. 654, pp. 453-472, 2010, doi: 10.1017/s0022112010000613.
[15] M. H. Dickinson, "Unsteady mechanisms of force generation in aquatic and aerial locomotion," American zoologist, vol. 36, no. 6, pp. 537-554, 1996.
[16] Y.-H. Chang, S.-C. Ting, J.-Y. Su, C.-Y. Soong, and J.-T. Yang, "Ventral-clap modes of hovering passerines," Physical Review E, vol. 87, no. 2, p. 022707, 2013.
[17] C. P. Ellington, C. Van Den Berg, A. P. Willmott, and A. L. Thomas, "Leading-edge vortices in insect flight," Nature, vol. 384, no. 6610, pp. 626-630, 1996.
[18] S. P. Sane, "The aerodynamics of insect flight," Journal of experimental biology, vol. 206, no. 23, pp. 4191-4208, 2003.
[19] D. D. Chin and D. Lentink, "Flapping wing aerodynamics: from insects to vertebrates," Journal of Experimental Biology, vol. 219, no. 7, pp. 920-932, 2016.
[20] V. M. Kramer, "Die zunahme des maximalauftriebes von tragflugeln bei plotzlicher anstellwinkelvergrosserung (boeneffekt)," Z. Flugtech. Motorluftschiff, vol. 23, pp. 185-189, 1932.
[21] M. H. Dickinson, F.-O. Lehmann, and S. P. Sane, "Wing rotation and the aerodynamic basis of insect flight," Science, vol. 284, no. 5422, pp. 1954-1960, 1999.
[22] S. J. Portugal et al., "Upwash exploitation and downwash avoidance by flap phasing in ibis formation flight," Nature, vol. 505, no. 7483, pp. 399-402, 2014.
[23] B. Tobalske and K. Dial, "Flight kinematics of black-billed magpies and pigeons over a wide range of speeds," Journal of Experimental Biology, vol. 199, no. 2, pp. 263-280, 1996.
[24] B. W. Tobalske, T. L. Hedrick, and A. A. Biewener, "Wing kinematics of avian flight across speeds," Journal of Avian Biology, vol. 34, no. 2, pp. 177-184, 2003.
[25] S. P. Sane and M. H. Dickinson, "The control of flight force by a flapping wing: lift and drag production," Journal of experimental biology, vol. 204, no. 15, pp. 2607-2626, 2001.
[26] K. E. Crandell and B. W. Tobalske, "Aerodynamics of tip-reversal upstroke in a revolving pigeon wing," Journal of Experimental Biology, vol. 214, no. 11, pp. 1867-1873, 2011.
[27] Q. Truong, Q. Nguyen, V. Truong, H. Park, D. Byun, and N. Goo, "A modified blade element theory for estimation of forces generated by a beetle-mimicking flapping wing system," Bioinspiration & biomimetics, vol. 6, no. 3, p. 036008, 2011.
[28] E. Chang, L. Y. Matloff, A. K. Stowers, and D. Lentink, "Soft biohybrid morphing wings with feathers underactuated by wrist and finger motion," Science Robotics, vol. 5, no. 38, 2020.
[29] B. Forouzi Feshalami, M. H. Djavareshkian, M. Yousefi, A. H. Zaree, and A. Mehraban Emroz, "Experimental investigation of flapping mechanism of the black-headed gull in forward flight," Proceedings of the Institution of Mechanical Engineers-Part G, vol. 235, 2018.
[30] J. W. Bahlman, S. M. Swartz, and K. S. Breuer, "Design and characterization of a multi-articulated robotic bat wing," Bioinspiration & biomimetics, vol. 8, no. 1, p. 016009, 2013.
[31] 陳威瀚, "以多自由度仿生撲翼機構分析雀類腕關節折曲運動於懸停飛行之氣動力效應," 碩士論文, 國立成功大學 航空與太空工程研究所, 2020.
[32] G. K. Taylor, R. L. Nudds, and A. L. Thomas, "Flying and swimming animals cruise at a Strouhal number tuned for high power efficiency," Nature, vol. 425, no. 6959, pp. 707-711, 2003.