(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.

Fig. 1. Wing motions. (A) Steady forward flight, (B) hovering using a pair of
motion in part a, (C) gliding (rotation of A), (D) gliding followed by a
vertical upstroke, (E) gliding followed by a lift-generating upstroke, and (F)
hovering using a mirror pair of E. Parameters:
d,u are the
angle of attack in down- and upstrokes, respectively, βd,u the
angle of the stroke plane, Ud,u the velocity, and
the fraction of time spent on the upstroke, i.e.
Uu/Ud=[(1–
)/
]/(sinβd/sinβu).