Two PhD students in National University of Singapore, Unmanned System Research Group spent four years in developing the novel hybrid unmanned aerial vehicles(UAV), U-Lion as shown in Figure 1. U-Lion is a hybrid UAV which can take-off and land vertically like helicopter UAVs, and transit to cruise flight like normal airplanes.
The wings can be fully retracted or expended, to favor the stability in VTOL mode or provide efficient lift in cruise flight. U-Lion is also able to fly autonomously includes vertical take-off and landing, cruise flight and autonomous transitions. The developed technology brings the application of hybrid UAVs one step closer.
Their research result has been published in Science China Information Sciences, Volume 60, Issue 3, 2017. The research work is mainly done by Wang Kangli, Ke Yijie under the supervision of Professor Chen.
Over the last decades, hybrid UAV has attracted worldwide interest for their potential applications in military and civilian operations, especially where there are severe constraints in their operating environment, for example, sea surveillance or forest mapping.
The VTOL capability minimizes the dependency of the take-off and landing facilities and cruise flying capability allows hybrid UAVs to perform long range and duration tasks. The hybrid UAV is a hot research topic not only academically, but also commercially. Many companies have devoted resources in developing hybrid UAVs, such as Google Project Wing.
However, due to the great difference in the structure for VTOL UAVs and fixed-wing UAVs, it is a huge challenge to combine the two functionalities into one single UAV. Previous attempts of hybrid UAVs tend to focus on either one of the flying modes, but not optimal on both. Besides, due to the high uncertain aerodynamic forces in the transition process, the transition process is difficult to automate.
To achieve optimal performance in both flying modes, U-Lion is designed in tail-sitter configurations with reconfigurable wings and vectoring thrust. U-Lion could adopt different flying modes based on the mission requirements, and adjust the wings to achieve optimal performance.
The ability allows U-Lion to fly much longer than typical VTOL UAVs and possess greater maneuverability compared to normal fixed wing UAVs. Advanced modelling and control algorithm is also developed for overcoming the uncertainties in transition and achieve autonomous full envelope flight.
"U-Lion, the autonomous hybrid UAV, has great potentials in many applications." Said Kangli, "The VTOL capability has widened its application environment and cruise capability enables it to performance long range tasks. The autonomous capability relieves the dependency of experience pilots and further expands its applications."
"Being optimal in both flying modes, U-Lion may bring a new way people operates drones. The fast reaction and static hovering capabilities bring U-Lion great potential in many applications, the VTOL capability allows it to operate in almost anywhere, including on vehicles on the sea." Said Ke Yijie, "In five to ten years' time, hybrid UAV will change the way people operate in areas like forest mapping, sea surveillance, power line inspection and disaster reaction. Being one of the best hybrid UAV, U-Lion will certainly lead the trend for future applications!"
See the article: Wang K L, Ke Y J, Chen B M. Autonomous reconfigurable hybrid tail-sitter UAV U-Lion. Sci China Inf Sci, 2017, 60(3): 033201, doi: 10.1007/s11432-016-9002-x
Wang Kangli | EurekAlert!
Study suggests buried Internet infrastructure at risk as sea levels rise
18.07.2018 | University of Wisconsin-Madison
Microscopic trampoline may help create networks of quantum computers
17.07.2018 | University of Colorado at Boulder
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Materials Sciences
18.07.2018 | Life Sciences
18.07.2018 | Health and Medicine