Wing-Tail Interactions in Near-Ground in Avian-Inspired Flight: An Experimental Approach

Quadcopters are unmanned aerial vehicles (UAVs) with four rotors. The configuration of the rotors is fixed, which limits their agility. Still, they dominate the UAV market. Flapping-wing UAVs that mimic the flight dynamics of birds are quieter and more maneuverable. They are underutilized because of challenges in landing and takeoff that require rapid changes in angle of attack. Birds have the required ability to perform rapid pitch-up motions during landing and takeoff while precisely sweeping their wings. If small UAVS could operate like birds, they could prove helpful in disaster response, reconnaissance, or package delivery. Most research has focused on the main wings alone, ignoring interactions between wings and tail. This project will conduct experiments to understand how interactions between wings and tails influence the forces and flow field during rapid starts and stops near the ground. By uncovering the physical principles that allow birds to maneuver effectively, the project will provide guidance for future designs of agile UAVs. The project will also support education and workforce development by integrating research findings into hands-on learning experiences and engaging graduate and undergraduate students. The project outcomes will improve low-altitude flight safety, enable more efficient near-ground operations, and support advanced manufacturing of UAVs and drones. This project will investigate the interaction of the main wing and tail during bird flight. The unsteady forces and the flow field around 3D printed bird models will be measured to understand how they change near the ground during takeoff or landing. The study will focus on how rapid pitching of the wing and tail influences the formation and evolution of vortices. The instantaneous forces, such as lift and drag, will be measured by a force sensor. The flow field will be measured using particle image velocimetry velocity measurements. The outcome of this project will reveal how different vortices formed during takeoff or landing govern force production during near-ground maneuvers, which will lead to improved mathematical models. The project will advance fundamental understandings of unsteady flows in complex, ground-adjacent conditions. Undergraduate and graduate students will be trained, and research findings will be integrated into coursework. Outreach activities will be conducted for high school students, where they will perform experiments with robotic bird wings. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2533390 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Samik Bhattacharya | Institution: The University of Central Florida Board of Trustees, ORLANDO, FL | Award Amount: $400,000 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2533390 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2533390.html