Session: 06-07 Adaptive Systems in Robotics and Control

Paper Number: 167839

167839 - Bio-Inspired Flaps for Flight Control During Dynamic Pitch Maneuvers 

Small-scale uncrewed aerial vehicles (sUAVs) have increased in importance over the past decade, emerging as a vital technology in many military and civilian applications, from surveillance and reconnaissance to crop management and energy harvesting. These applications cover a wide range of operational environments, from clear, open spaces that require efficiency to densely populated urban areas that experience undesired perturbations such as gusts and turbulence. Being small in size, sUAVs are especially prone to these disturbances, hence, maintaining flight control effectiveness across such a wide range of environmental conditions is mission-critical, and a multifunctional flight control effector capable of generating sufficient control authority for both maneuver control and stability augmentation under static and dynamic conditions is required. Birds, in contrast to sUAVs, are incredible fliers with a versatile flying system that enables them to navigate complex environments, thanks in part to their multiple feather structures. In particular, the covert feathers located on both the suction and pressure sides of a bird’s wing play a crucial role in this improved flight performance. In this paper, we propose the use of bio-inspired flaps based on these covert feathers, called covert-inspired flaps, for flight control under dynamic maneuver conditions. While previous studies have demonstrated that these covert-inspired flaps are effective in flight control under steady-state, static flow conditions, no one has explored the efficacy of such devices for flight control during dynamic maneuver conditions. This study uses an experimental approach where we utilize Princeton’s closed-loop, closed test section wind tunnel to measure the aerodynamic forces and moments generated by covert-inspired flap deflections at various chordwise locations on a 2D NACA 2414 airfoil under a dynamic pitch-up maneuver. The study investigates both single-sided deflections, where only the pressure-side or suction-side flaps are deployed, and double-sided deflections, in which both the pressure and suction side flaps are deployed simultaneously. Additionally, we measure the vorticity and velocity flow fields using time-resolved particle image velocimetry (PIV), which facilitates an understanding of the physical mechanisms underlying the observed changes in aerodynamic response. Moreover, we use a data-driven modeling approach to derive an empirical expression that predicts the dynamic stall angle of attack and maximum lift coefficient based on the covert-inspired flap location and static lift information. Finally, we present a case study that outlines an approach for configuration selection tailored to different desired mission profiles, thereby demonstrating the practical implications of our findings. Overall, this work demonstrates that covert-inspired flaps maintain control effectiveness even under dynamic conditions, thereby expanding the flight envelope of sUAVs and increasing their mission versatility.

Presenting Author: Aimy Wissa Princeton University

Presenting Author Biography: Prof. Aimy Wissa joined the Mechanical and Aerospace Engineering Department at Princeton University as an Assistant Professor in January 2022. Before Princeton, she was an Assistant Professor in the Mechanical Science and Engineering department at the University of Illinois at Urbana-Champaign. She is the director of the Bio-Inspired Adaptive Morphology (BAM) Lab. Wissa was a post-doctoral fellow at Stanford University, and she earned her doctoral degree in Aerospace Engineering from the University of Maryland in 2014. Wissa’s work focuses on the modeling and experimental evaluation of dynamic and adaptive bioinspired structures and systems, such as avian-inspired and insect-inspired wings and robotic systems with multiple modes of locomotion. Wissa is a McNair Scholar. She has received numerous awards, including the Air Force Office of Scientific Research Young Investigator and NSF’s CAREER awards.