Dynamics, Stability & Control of Flapping Wing Robots


• 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)


• 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.