Dynamics, Stability & Control of Flapping Wing Robots
Objectives
• Understand the nonlinear dynamics, stability, and control of various biomimetic flapping wing designs featuring
• Analysis of wing flexibility
• Consideration of wing mass
• Non-naïve averaging methods
• Primary focus area: determine the influence of wing flexibility on the stability of flapping wing designs and optimal stiffness, mass, and wing loading for aerodynamic performance and stability
• Develop robust nonlinear control strategies for this nonlinear, time periodic system across the entire flight envelope
Approach - Multi-fidelity Analysis
Motivation - Bumblebees
• Can hover or sustain forward flight at high advance ratios
• Maintains trajectory in unsteady wind conditions
• Exhibits rapid accelerations and decelerations
• Can carry loads exceeding their body weight
exhibits significant chordwise flexibility (2)
Achievements
• Developed full multi-body mathematical model for multiple winged insects/vehicles from first principles and verified the result against other models in the literature
• Developed aerodynamic pitching moment predictions based on both unsteady aerodynamic theory and full direct numerical simulation of the incompressible Navier Stokes equations
• Implemented a fully coupled open loop flight dynamic solver with multiple aerodynamic models
Future Work
• Fully coupled CFD-CSD-EOM solver
• Stability analysis using advanced techniques
• Nonlinear control implementation
• Model free control development
Researchers (more info here)
• Dr. Chang-kwon Kang, Assistant Professor, MAE • Ph.D. Student: Major James E. Bluman, P.E.
Current Results - to be presented at AIAA SciTech in January 2016 (abstract pending acceptance)
Effects of Wing Mass on Dynamic Simulation
These figures show that the inclusion of wing mass in the multi-body simulation has a significant effect on the longitudinal dynamic response of the body/fuselage to the high frequency forcing of the flapping wings
(m = 0 denoted wing mass omitted; m = 1 denotes full wing mass included in the simulation).
Key References
1. Kang, C. and Shyy, W., Scaling law and enhancement of lift generation of an insect-size hovering flexible wing,” Journal of Royal Society Interface, Vol. 10 no. 85, 2013
2. Sridhar, M. K., and Kang, C., “Aerodynamic Performance of Two-Dimensional, Chordwise Flexible Flapping Wings at Fruit Fly Scale in Hover Flight,” Bioinspiration & Biomimetics, Vol. 10, Nr. 3, 2015, p. 036007.
3. Liu, H., Nakata, T., Gao, N., Maeda, M., Aono, H., and Shyy, W., “Micro Air Vehicle-Motivated Computational Biomechanics in Bio-Flights:
Aerodynamics, Flight Dynamics and Maneuvering Stability,” Acta Mechanica Sinica, Vol. 26, Nr. 6, 2010, pp. 863–879.