No Access

Design and Implementation of a Thrust-Vectored Unmanned Tail-Sitter with Reconfigurable Wings

Unmanned System Research Group, The National University of Singapore, Singapore 117583, Singapore

NUS Graduate School for Integrative Sciences and Engineering, The National University of Singapore, Singapore 117456, Singapore

Search for more papers by this author

Tao Pang

Temasek Laboratories, The National University of Singapore, Singapore 117411, Singapore

Search for more papers by this author

Kun Li

Unmanned System Research Group, The National University of Singapore, Singapore 117583, Singapore

Search for more papers by this author

Kangli Wang

Unmanned System Research Group, The National University of Singapore, Singapore 117583, Singapore

Search for more papers by this author

Yijie Ke

Unmanned System Research Group, The National University of Singapore, Singapore 117583, Singapore

Search for more papers by this author

, and

Ben M. Chen

Unmanned System Research Group, The National University of Singapore, Singapore 117583, Singapore

Search for more papers by this author

https://doi.org/10.1142/S2301385015500090Cited by:14 (Source: Crossref)

Abstract

In this paper, we present the development of a reconfigurable hybrid unmanned aerial vehicle (UAV): U-Lion [Ang et al., 11th IEEE Int. Conf. Control Automation (ICCA), pp. 750–755]. U-Lion is a small-scale UAV that is capable of vertical takeoff and landing (VTOL) and fixed-wing Cruise modes through its unique mechanical design. Mainly built with carbon fiber and expanded polyolefin (EPO) foam, U-Lion is equipped with an array of avionic components which enable stable control of the UAV both in VTOL and Cruise modes. It was employed by the National University of Singapore (NUS) Unmanned System Research Group to participate in the 2013 UAV Grand Prix (UAVGP) competition held in Beijing, China. Its design adopts a reconfigurable wing and a tail-sitter structure, which combines the advantages of a fixed-wing plane and a rotor helicopter effectively. U-Lion could transit from vertical takeoff to a hovering stage before flying in Cruise mode to realize efficient long duration flight. The propulsion of U-Lion comes from a self-fabricated contra-rotating motor fixed on a gimbal mechanism which can change the direction of the motor for the required thrust. This thrust-vectored propulsion system primarily provides control in the VTOL mode but also enhances flight capabilities in Cruise mode. The maximum thrust provided by the motor can be as high as 40 N and it provides six degree of motion controls in VTOL mode. U-Lion has a few special internal designs to empower its capabilities: (1) Reconfigurable wings allow the U-Lion to adapt to different flying modes. (2) Adaptive center of gravity (CG) by adjusting the battery position to fulfill the different requirements of CG for VTOL mode and Cruise mode. (3) Unique contra-rotating thrust-vectored propulsion system. The detailed design and implementation procedure have been presented in this paper along with our computational fluid dynamics (CFD) simulation results, real flight tests and competition performance.

This paper was recommended for publication in its revised form by Co-Editor-in-Chief, Lihua Xie.

Keywords:

References

K. Z. Anget al., Development of an unmanned tail-sitter with reconfigurable wings: U-Lion, 11th IEEE Int. Conf. Control & Automation (ICCA) (2014) pp. 750–755. Google Scholar
J. A. Guerreroet al., Robust control design based on sliding mode control for hover flight of a mini tail-sitter unmanned aerial vehicle, 35th Annual Conf. IEEE Industrial Electronics, 2009. IECON'09 (IEEE, 2009) pp. 2342–2347. Google Scholar
K. Jacksonet al., Unmanned Syst. 1(2), 199 (2013). Link, Google Scholar
E. Cetinsoyet al., Turk. J. Electr. Eng. Comput. Sci. 19(5), 733 (2011). Google Scholar
H. Stone, Aerodynamic modelling of a wing-in-slipstream tail-sitter UAV, 2002 Biennial International Powered Lift Conf. Exhibit (2002) pp. 5–7. Google Scholar
J. Escarenoet al., Modeling and control strategy for the transition of a convertible tail-sitter UAV, European Control Conf. (2007) pp. 2–5. Google Scholar
W. Shyyet al., Prog. Aerosp. Sci. 46(7), 284 (2010). Crossref, Google Scholar
www.rheinmetall.com . Google Scholar
G. Caiet al., Mechatronics 18(10), 545 (2008). Crossref, Google Scholar
M. Drela, Low Reynolds Number Aerodynamics (Springer, Berlin, Heidelberg, 1989) pp. 1–12. Crossref, Google Scholar
I. Palunko and R. Fierro, Adaptive control of a quadrotor with dynamic changes in the center of gravity, Proc. 18th IFAC World Congress18 (2011) pp. 2626–2631. Google Scholar
J. J. Bertin and M. L. Smith , Aerodynamics for Engineers 1 ( Prentice Hall , Englewood Cliffs , 1989 ) . Google Scholar
J. D. Anderson Jr. , Fundamentals of Aerodynamics ( Tata McGraw-Hill Education , 1985 ) . Google Scholar
E. N. Jacobs, K. E. Ward and R. M. Pinkerton, The characteristics of 78 related airfoil sections from tests in the variable-density wind tunnel, Report No. NACA-TR-460, National Aeronautics and Space Admin Langley Research Center Hampton, VA (1933) . Google Scholar
R. R. Bulatovic and S. R. Dordevic, Theor. Appl. Mech. 31(4), 265 (2004). Crossref, Google Scholar
H. R. Kelly, J. Aeronaut. Sci. 21(8), (2012). Google Scholar
J. E. Shigley , Shigley's Mechanical Engineering Design ( Tata McGraw-Hill Education , 2011 ) . Google Scholar
P. Kurowski , Engineering Analysis with SolidWorks Simulation 2013 ( SDC Publications , 2013 ) . Google Scholar