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Fig. 2. Enhancement of mean lift coefficient for different near-clap conditions
scaled to the performance of a single flapping robotic wing. The magnitude of
lift coefficient CL augmentation is 1.0 at large
separation angles where the lift coefficients for one-wing and two-wing
flapping are equal. Due both to the separation between the two wing hinges
(gear box of the robot) and the rigidity of the model wing, the wings are
closest at their tips (blue). Adding spacers at the wing hinge (red) reduces
the dead space within the gap formed by the two wings during the clap. This
experimental modification results in a higher aerodynamic performance at
minimum angular distance between the two wings.