Aerodynamic Drag of a Tilt-Rotor UAV During Forward Flight in Rotary-Wing Mode
1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
5-41-10 Koishikawa, Bunkyo-ku, Tokyo 112-0002, Japan
2-1 Minamijosanjima-cho, Tokushima 770-8506, Japan
This paper examines the aerodynamic drag force acting on a tilt-rotor UAV that has three mini fans and a main rotor with a tilt mechanism. The mini fans are embedded in the nose and the left and right wings. The main rotor is located near the center of the vehicle, and its front half is surrounded by the trailing edge of the nose in rotary-wing mode. The downward airflow from the fans and the main rotor generates an aerodynamic drag force called momentum drag, which is linearly proportional to the airspeed of UAV. To verify the existence of momentum drag, parameter identification of drag coefficients is performed from experimental data where the UAV flies forward in rotary-wing mode. The drag force is also investigated using computational fluid dynamics simulations. These experimental and numerical results are consistent with theoretical results based on momentum theory.
-  K. Nonami, “Drone technology, cutting-edge drone business, and future prospects,” J. Robot. Mechatron., Vol.28, No.3, pp. 262-272, 2016.
-  A. S. Saeed, A. B. Younes, S. Islam, J. Dias, L. Seneviratne, and G. Cai, “A review on the platform design, dynamic modeling and control of hybrid UAVs,” Proc. of 2015 Int. Conf. on Unmanned Aircraft Systems, pp. 806-815, 2015.
-  D. F. Finger, C. Braun, and C. Bil, “A review of configuration design for distributed propulsion transitioning VTOL aircraft,” Proc. of the 2017 Asia-Pacific Int. Symposium on Aerospace Technology, pp. 1782-1796, 2017.
-  P. M. Rothharr, P. C. Murphy, B. J. Bacon, I. M. Gregory, J. A. Grauer, R. C. Busan, and M. A. Croom, “NASA Langley distributed propulsion VTOL tilt-wing aircraft testing, modeling, simulation, control, and flight test development,” Proc. of 14th AIAA Aviation Technology, Integration, and Operations Conf., AIAA 2014-2999, 2014.
-  B. W. McCormick, Jr., “Aerodynamics of V/STOL flight,” Dover, 1999.
-  N. Thouault et al., “Experimental investigation of the aerodynamic characteristics of generic fan-in-wing configurations,” The Aeronautical J., Vol.113, No.1139, pp. 9-20, 2009.
-  R. E. Kuhn, R. J. Margason, and P. Curtis, “Jet induced effects: the aerodynamics of jet and fan powered V/STOL aircraft in hover and transition,” Progress in Astronautics and Aeronautics, Vol.217, AIAA, 2006.
-  A. J. Saddington and K. Knowles, “A review of out-of-ground-effect propulsion-induced interference on STOVL aircraft,” Progress in Aerospace Sciences, Vol.41, Issues 3-4, pp. 175-191, 2005.
-  H. H. Heyson, “Theoretical and experimental investigation of the performance of a fan-in-wing VTOL configuration,” NASA TN D-7498, 1973.
-  M. S. Selig, “Modeling propeller aerodynamics and slipstream effects on small UAVs in realtime,” Proc. of AIAA Atmospheric Flight Mechanics 2010 Conf., AIAA 2010-7938, 2010.
-  D. Rohr, M. Studiger, T. Stastny, N. R. J. Lawrance, and R. Siegwart, “Nonlinear model predictive velocity control of a VTOL tiltwing UAV,” IEEE Robotics and Automation Letters, Vol.6, No.3, pp. 5776-5783, 2021. https://doi.org/10.1109/LRA.2021.3084888
-  B. Li, J. Sun, W. Zhou, C.-Y. Wen, K. H. Low, and C.-K. Chen, “Transition optimization for a VTOL tail-sitter UAV,” IEEE/ASME Trans. on Mechatronics, Vol.25, No.5, pp. 2534-2545, 2020. https://doi.org/10.1109/TMECH.2020.2983255
-  J. B. Willis and R. W. Beard, “Pitch and thrust allocation for full-flight-regime control of winged eVTOL UAVs,” IEEE Control Systems Letters, Vol.6, pp. 1058-1063, 2022.
-  K. Kita, A. Konno, and M. Uchiyama, “Hovering control of a tail-sitter VTOL aerial robot,” J. Robot. Mechatron., Vol.21, No.2, pp. 277-283, 2009.
-  C. Kikumoto, T. Urakubo, K. Sabe, and Y. Hazama, “Back-transition control with large deceleration for a dual propulsion VTOL UAV based on its maneuverability,” IEEE Robotics and Automation Letters, Vol.7, No.4, pp. 11697-11704, 2022.
-  R. W. Beard and T. W. McLain, “Small unmanned aircraft: theory and practice,” Princeton University Press, 2012.
-  E. A. Morelli, “Practical aspects of the equation-error method for aircraft parameter estimation,” Proc. of AIAA Atmospheric Flight Mechanics Conf. and Exhibit, AIAA 2006-6144, 2006.
-  G. V. Shankaran and M. B. Dogruoz, “Validation of an advanced fan model with multiple reference frame approach,” Proc. of 2010 12th IEEE Intersociety Conf. on Thermal and Thermomechanical Phenomena in Electronic Systems, 2010.
-  H. K. Versteeg and W. Malalasekera, “An introduction to computational fluid dynamics,” 2nd ed., Pearson Education Limited, Harlow, 2007.
This article is published under a Creative Commons Attribution-NoDerivatives 4.0 Internationa License.