During soaring forward flight, larger birds such as raptors generate most of their lift in a manner consistent with the lift generated by fixed-wing aircraft. However, in flapping flight there is an additional flow field that must be superimposed to account for thrust generated. The aerodynamic forces can be analyzed using conventional strip theory techniques and integrated across the wingspan and over the entire flapping cycle. Oscillating wing pitch causes the lift vector to contribute to forward thrust and effects useful angles of attack. This paper seeks to predict which kinematic parameters of flapping flight will allow for sustained forward flight. Using a mathematical model for flapping flight and a genetic algorithm, kinematic parameters are selected that provide sufficient lift and thrust while attenuating aerodynamic power consumption. The results show that separate degrees of freedom are necessary for twisting and heaving motions to yield acceptable flight conditions.

1.
DeLaurier
J. D.
,
1993
, “
An Aerodynamic Model for Flapping-Wing Flight
,”
Aeronautical Journal
,
97
, pp.
125
130
.
2.
DeLaurier
J. D.
,
1993
, “
The Development of an Efficient Ornithopter Wing
,”
Aeronautical Journal
,
97
, pp.
153
162
.
3.
DeLaurier
J. D.
,
1999
, “
The Development and Testing of a Full-Scale Piloted Ornithopter
,”
Canadian Aeronautics and Space Journal
,
45
No.
2
, pp.
72
82
.
4.
Larijani, R. F., and DeLaurier, J. D., 2001, “A Nonlinear Aeroelastic Model for the Study of Flapping Wing Flight,” Fixed and Flapping Wing Aerodynamics for Micro Air Vehicle Applications (ed. T.J. Mueller), AIAA, Reston, pp. 399–428.
5.
Van Den Berg
C.
, and
Rayner
J. M. V.
,
1995
, “
The Moment of Inertia of Bird Wings and the Inertial Power Requirement for Flapping Flight
,”
The Journal of Experimental Biology
,
198
, pp.
1655
1664
.
6.
Liu, T., Kuykendoll, K., Rhew, R., and Jones, S., 2004, “Avian Wings,” Proc., 24th AIAA Aerodynamic Measurement Technology and Ground Testing Conference, pp. 1–23.
7.
Tobalske
B. W.
,
Hedrick
T. L.
,
Biewener
A. A.
,
2003
, “
Wing Kinematics of Avian Flight Across Speeds
,”
Journal of Avian Biology
,
34
, pp.
177
184
.
8.
Chai
P.
, and
Millard
D.
,
1997
, “
Flight and Size Constraints: Hovering Performance of Large Hummingbirds Under Maximal Loading
,”
The Journal of Experimental Biology
,
200
, pp.
2757
2763
.
9.
Vest
M. S.
, and
Katz
J.
,
1996
, “
Unsteady Aerodynamic Model of Flapping Wings
,”
AIAA Journal
,
34
No.
7
, pp.
1435
1440
.
10.
Patil
M. J.
,
2003
, “
From Fluttering Wings to Flapping Flight: the Energy Connection
,”
Journal of Aircraft
,
40
No.
2
, pp.
270
276
.
11.
Jones
R. T.
,
1980
, “
Wing Flapping with Minimum Energy
,”
Aeronautical Journal
,
84
, pp.
214
217
.
12.
Keennon, M. T., and Grasmeyer, J. M., 2003, “Development of the Black Widow and Microbat MAVs and a Vision of the Future of MAV Design,” Proc. AIAA/ICAS International Air and Space Symposium and Exposition: The Next 100 Years, Dayton, Ohio, pp. 1–11.
13.
Jones, R. T., 1940, “The Unsteady Lift of a Wing of Finite Aspect Ratio,” NACA Report No. 681.
14.
Cox, A., 2003, “Analysis of Power and Lift for a Hovering Piezoelectrically Actuated Flapping Wing Micro-Aerial Vehicle,” Ph. D. thesis, Vanderbilt University, Nashville, TN.
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