隨著科技的發展，飛機的應用日益廣泛，各種因應不同需求所開發的飛機逐漸問世。根據文獻蒐集結果，大多數研究著重於減震系統設計或飛機結構震動分析，少有起落架機構之設計。本研究提出一套系統化的主起落架機構設計流程，建立分析與合成的數學模型，並以PC-9飛機為設計實例說明，以為研發主起落架機構設計的參考。
　　初步設計為設計起落架放置位置的步驟，應用氣體動力學理論設計起落架高度、輪距、以及軸距等設計參數。根據初步設計結果，以PC-9飛機為現有設計並應用創意性機構設計方法，推演出所有與現有設計具相同拓樸構造特性之機構構形。本研究選用2種主起落架機構構形，依序進行尺寸合成、運動分析與力分析方程式之推導。
　　所選用的兩個機構構形，包含由一個致動器與一個四連桿機構所組成的平面六連桿機構，完成主起落架收放作動，以及由一個致動器與一個球面四連桿所組成的空間六連桿機構，完成收放與輪轉之作動。兩個機構構形皆以函數衍生合成目標，設計機構桿件尺寸；其中，平面機構與空間機構分別以Chebyshev spacing合成方法、Freudenstein方程式、以及最佳化方法完成機構尺寸之設計。
　　平面機構與空間機構的運動分析模型，可分別依照向量迴路法與坐標轉換矩陣理論建立。接著，畫出各動桿之受力自由體圖，並以牛頓法列出機構各移動桿之力與力矩平衡方程式；另，致動器所需提供之致動力與各桿間之力與力矩交互作用力，可由牛頓法所列出各動桿之力與力矩平衡方程式所求得，並利用商用軟體ADAMS驗證力分析之結果。此外，亦將主起落架機構之設計與分析流程程式化。
　　總的來說，本研究針對起落架開發與研究工作，提出一套主起落架機構設計流程，可有效率地建立起落架機構之尺寸合成、運動分析、以及力分析之數學模型。

　　With the development of science and technology, aircrafts have various applications nowadays. Numerous literatures study the design and analysis of airframes regarding the analysis of damping system and structural vibrations. However, very few literatures focus on the investigation of the design process for the landing gear mechanisms. This work proposes a systematic methodology for the design of aircraft main landing gear system based on the methodology of creative mechanism design, dimensional synthesis, kinematic analysis, and dynamic force analysis. And, the PC-9 aircraft is adapted as an example.
　　Preliminary design is a step to determine the basic geometry requirements of the landing gear mechanism based on the landing gear height, the distance between the main landing gear and the center of gravity of the aircraft, the wheelbase, and the wheel track. The landing gear mechanism of the PC-9 aircraft is then selected for further analysis purposes. All possible mechanisms having the same topological characteristics as the PC-9 are synthesized using the creative mechanism design methodology.
　　Two of the synthesized mechanisms are then chosen to perform the retraction motion and wheel-twisting motion of the main landing gear system. The first mechanism is a planar six-bar linkage consisting of an actuator and a four-bar linkage, while the second mechanism is a spatial six-bar linkage consisting of an actuator and a spherical four-bar linkage. The dimensions of the links in the two mechanisms are determined using the Chebyshev spacing synthesis method and the Freudenstein equation for the planar mechanism and an optimization method for the spatial linkage mechanism.
　　Kinematic models of the planar retraction and the spatial wheel-twisting mechanisms are then established using the vector loop method and coordinate transformation matrix method, respectively. A dynamic force analysis model is constructed for each mechanism based on the free body diagrams of the moving members within the system. Finally, the force analysis models are used to determine the actuation force and interaction forces and moments between the adjacent links in the two mechanisms. In addition, the dynamic force analysis results are verified by means of numerical simulations performed using commercial ADAMS software. Moreover, the design and synthesis procedures in the proposed framework are implemented in the form of self-written computer code.
　　In summary, this work provides an efficient and powerful approach for the research and development of the main landing gear mechanism of aircrafts.

[1]陳皇鈞，1989，牛頓工程辭典，牛頓出版股份有限公司，台北，台灣。
[2]黃振榮，1983，主起落架收放與輪轉機構之運動設計，碩士論文，國立成功大學機械工程學系，台南。
[3]Conway, H. G., 1958, Landing gear design (Vol. 3), Chapman & Hall, London, England.
[4]Gerd, R., 2002, “Aircraft Landing Gear - The Evolution of a System”, 15 May 2017, < http://www.fzt.haw-hamburg.de/pers/Scholz/dglr/hh/text_2002_04_11_Fahrwerk>
[5]Landing Gear Types, “Aeronautical Guide: Landing Gear Types - Aircraft systems”, 15 May 2017, <http://okigihan.blogspot.com/p/landinggear-types-aircraft-landing-gear.html>.
[6]Walter, J. B., “Airplane - Early technology”, 10 Oct. 2018, <https://www.britannica.com/technology/airplane/Types-of-aircraft>.
[7]James, B., 2014, “Condor”, 15 May 2017, <http://worldwartwo.filminspector.com/2014/12/focke-wulf-fw-200-condor.html>.
[8]B-29, “Boeing B-29 Superfortress Assembly Plants, & Production Numbers”, 15 May 2017, <http://www.b29-superfortress.com/b29-superfortress-production-assembly-plants.htm>.
[9]Transport B-52 Bomber, 2009, “Can You Transport a B-52 Bomber on an Aircraft Carrier?”, 10 Oct. 2018, <https://www.veteranstodayarchives.com/2009/05/10/can-you-transport-a-b-52-bomber-on-an-aircraft-carrier/>.
[10]辛建周，1995，空間6R型起落架收放與輪轉機構之運動研究，碩士論文，國立成功大學機械工程學系，台南。
[11]李聰慶，1990，可動空間nR過度拘束連桿組，博士論文，國立成功大學機械工程學系，台南。
[12]Funnell, R., 1989, Flight Manual - PC9/A(AAP 7212.007-1), Royal Australian Air Force, Australia.
[13]Grossman, S. P., 2002, Landing gear, U.S. Patent No. 6,349,901.
[14]Ward, E. G., 1946, Retractable landing gear, U.S. Patent No. 2,392,892.
[15]Rene, L. L., 1938, Retractable landing gear, U.S. Patent No. 2,109,427.
[16]Large, D. T. and Veenstra, G. N., 1992, Retractable landing gear with self-braced folding strut, U.S. Patent No. 5,100,083.
[17]Kendall, G. A. and Minick, R., 1979, Aircraft landing gear assembly, U.S. Patent No. 4,147,316.
[18]邱正一、朱鈞偉，2006，飛機起落架空間四連桿輪轉機構，中華民國專利，公告第00413號。
[19]Martin, H., 2017, “F-104 Landing Gear”, 12 May 2018, <https://www.youtube.com/watch?v=fY642w5IzsQ&t=5s>.
[20]F-15 Landing Gear, 2011, “F-15 Fighter Jet MLG Retraction and Extension Kinematics”, 12 May 2018, <https://www.youtube.com/watch?v=rLpoozO8Gb0>.
[21]Gerald, R., 2010, “Large F16 Gear Test”, 12 May 2018, <https://www.youtube.com/watch?v=XODoZbavs6g>.
[22]Junkers Ju-88 Gear Test, 2011, “Junkers Ju 88 Gear Test”, 12 May 2018, <https://www.youtube.com/watch?v=UmhuCHgBBsU&t=12s>.
[23]Vigilante Landing Gear, 2015, “1/6 Scale Vigilante Main Landing Gear”, 12 May 2018, <https://www.youtube.com/watch?v=TLIMthjJKX8&t=9s>.
[24]Roger, A. R., 1952, Retractable landing gear for aircraft, U.S. Patent No. 2,589,434.
[25]Lucien, R., 1961, Retractable landing gear, U.S. Patent No. 2,982,500.
[26]Hawkins, J. W. M., 1949, Main landing gear, U.S. Patent No. 2,487,548.
[27]Grossman, S. P., 2002, Landing gear, U.S. Patent No. 6,481,668.
[28]Hartel, E., 1974, Main landing gear, U.S. Patent No. 3,822,048.
[29]Rene, L. L., 1939, Self-folding strut for airplane landing chassis, U.S. Patent No. 2,154,984.
[30]Yin, Y., Neild, S. A., Jiang, J. Z., Knowles, J. A., and Nie, H., 2017, Optimization of a main landing gear locking mechanism using bifurcation analysis. Journal of Aircraft, 54(6), 2126-2139.
[31]Knowles, J. A., Krauskopf, B., and Lowenberg, M., 2013, Numerical continuation analysis of a three-dimensional aircraft main landing gear mechanism. Nonlinear Dynamics, 71(1-2), 331-352.
[32]Cleghorn, W. L. and Dechev, N., 2014, Mechanics of Machines, Oxford University Press, 2nd edition, UK.
[33]Hall, A. S. and Goodman, T. P., 1961, Kinematics and linkage design. Journal of Applied Mechanics, 28, 639.
[34]Erdman, A. G., Sandor, G. N., and Kota, S., 1997, Mechanism design: Analysis and synthesis. Vol. 1. Prentice-Hall, London, England.
[35]Hirschhorn, J., 1962, Kinematics and dynamics of plane mechanisms, McGraw-Hill, New York.
[36]Hartenberg, R. and Danavit, J., 1964, Kinematic synthesis of linkages, McGraw-Hill, New York.
[37]Primrose, E. J. F. and Freudenstein, F., 1969, Spatial Motions I—Point paths of mech-anisms with four or fewer links, ASME Transactions, Journal of Engineering for Industry, 91(1), 103-113.
[38]Hsia, L. M. and Yang, A. T. (1981), On the principle of transference in three-dimensional kinematics, ASME Transactions, Journal of Mechanical Design, 103(3), 652-656.
[39]Erdman, A. G., Sandor, G. N., and Kota S., 1984, Advanced Mechanism Design: Analysis and Synthesis, Vol. 2, Pearson, London, England.
[40]Uicker, J. J., Denavit, J., and Hartenberg, R. S., 1964, An iterative method for the displacement analysis of spatial mechanisms. Journal of Applied Mechanics, 31(2), 309-314.
[41]Dimentberg, F. M., 1950, The determination of the positions of spatial mechanisms, Izdatelstvo Moskovskogo Universiteta, Moskva.
[42]Cheng, H. H., and Thompson, S., 1995, Computer-aided displacement analysis of spatial mechanisms using the CH programming language, Advances in Engineering Software, 23(3), 163-172.
[43]Razi, R., 1963, Static Force Analysis of Spatial Mechanisms by the Matrix Method, Doctoral dissertation, Northwestern University, Evanston, Illinois, USA.
[44]Denavit, J., Hartenberg, R. S., Razi, R., and Uicker, J. J., 1965, Velocity, acceleration, and static-force analyses of spatial linkages, ASME Transactions, Journal of Applied Mechanics, 32(4), 903-910.
[45]Uicker, J. J., 1967, Dynamic force analysis of spatial linkages, ASME Transactions, Journal of applied mechanics, 34(2), 418-424.
[46]Lee, P. J. and Bagci, C., 1975, The RCRRC five-link space mechanism - Displacement analysis, force and torque analysis and its transmission criteria, ASME Transactions, Journal of Engineering for Industry, 97(2), 581-594.
[47]Yang, A. T., 1969, Displacement analysis of spatial five-link mechanisms using (3× 3) matrices with dual-number elements, ASME Transactions, Journal of Engineering for Industry, 91(1), 152-156.
[48]Yang, A. T. and Freudenstein, F., 1964, Application of dual-number quaternion algebra to the analysis of spatial mechanisms, Journal of Applied Mechanics, 31(2), 300-308.
[49]McCarthy, J. M., 1986, Dual orthogonal matrices in manipulator kinematics, The International Journal of Robotics Research, 5(2), 45-51.
[50]Duffy, J. and Habib-Olahi, H. Y., 1971, A displacement analysis of spatial five-link 3R-2C mechanisms - I. On the closures of the RCRCR mechanism, Journal of Mechanisms, 6(3), 289-301.
[51]Duffy, J. and Habib-Olahi, H. Y., 1972, A displacement analysis of spatial five-link 3R-2C mechanisms Part 3. Analysis of the RCRRC mechanism, Mechanism and Machine Theory, 7(1), 71-84.
[52]Yuan, M. S., 1971, Displacement analysis of the RCRCR five-link spatial mechanism, Journal of Mechanisms, 6(1), 119-134.
[53]Jamalov, R. I., Litvin, F. L., and Roth, B., 1984, Analysis and design of RCCC linkages, Mechanism and Machine Theory, 19(4-5), 397-407.
[54]Marble, S. D. and Pennock, G. R., 2000, Algebraic-geometric properties of the coupler curves of the RCCC spatial four-bar mechanism, Mechanism and Machine Theory, 35(5), 675-693.
[55]Uicker, J. J., 1963, Velocity and Acceleration Analysis of Spatial Mechanisms Using 4 X 4 Matrices, Northwestern University, the Technological Institute, Evanston, Illinois, USA.
[56]Yang, A. T., 1965, Static force and torque analysis of spherical four-bar mechanisms, ASME Transactions, Journal of Engineering for Industry, 87(2), 221-227.
[57]Ma, O. and Angeles, J., 1988, Performance evaluation of path-generating planar, spherical and spatial four-bar linkages, Mechanism and Machine Theory, 23(4), 257-268.
[58]Mohammad, H. S., 2012, Aircraft Design: A Systems Engineering Approach, John Wiley & Sons, UK.
[59]Yan, H. S., 1992, A methodology for creative mechanism design, Mechanism and Machine Theory, 27(3), 235-242.
[60]Alizade, R. I. and Kilit, Ö., 2005, Analytical synthesis of function generating spherical four-bar mechanism for the five precision points, Mechanism and Machine Theory, 40(7), 863-878.
[61]Zimmerman, J. R., 1967, Four-precision-point synthesis of the spherical four-bar function generator, Journal of Mechanisms, 2(2), 133-139.
[62]Chu, J. and Sun, J., 2010, Numerical atlas method for path generation of spherical four-bar mechanism, Mechanism and Machine Theory, 45(6), 867-879.
[63]Sun, J. and Chu, J., 2007, Synthesis of spherical four-bar function generator by means of Fourier method, In 12th IFToMM World Congress (pp. 18-21). Besançon, France.
[64]Ginsberg, J. H., 2008, Engineering Dynamics (Vol. 10), Cambridge University Press, Cambridge, England.
[65]Ginsberg, J. H., 1998, Advanced engineering dynamics, Cambridge University Press, Cambridge, England.
[66]Perkins, D. A., Turner, M. L., and Murray, A. P., 2007, Static analysis of torque and coupler driven spherical four-bar mechanisms with an applied load, ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference (pp. 519-526).
[67]Bagci, C., 1972, Dynamic force and torque analysis of mechanisms using dual vectors and 3× 3 screw matrix, ASME Transactions, Journal of Engineering for Industry, 94(2), 738-745.