Рубрики:
WING-BEAT FREQUENCY
TETHERED FLIGHT
LOCUSTA-MIGRATORIA
LIFT
LEPIDOPTERA
KINEMATICS
PAPILIONOIDEA
DROSOPHILA
BEHAVIOR
TUNNEL
WING-BEAT FREQUENCY
TETHERED FLIGHT
LOCUSTA-MIGRATORIA
LIFT
LEPIDOPTERA
KINEMATICS
PAPILIONOIDEA
DROSOPHILA
BEHAVIOR
TUNNEL
Аннотация: Vertical and horizontal periodic movements of the body following each wing stroke were investigated in three butterfly species during their free flight in a transparent cage. Distribution of the movements along the stroke cycle shows that specimens climb during downstroke, supination, and upstroke. Pronation of the wings in the top of their trajectory (Weis-Fogh's clap-and-fling mechanisms) is followed by height reduction. The horizontal distance that insects cover during pronation and downstroke exceeded mean value and it was less than the mean value during supination and upstroke. The data acquired suggest that distributions in lift and thrust along a stroke cycle are characterized by sinusoid-like curves as a first approximation. Maximal lift is generated during the end of each downstroke, while the maximal thrust coincides in time with the end of the upstroke and the clap of the wings. A new non-steady mechanism of aerodynamic force generation is proposed. The mechanism is connected with air throwing off the flapping planes during their pronation and supination. Horizontal flight speed is negatively correlated with the angle between the body and the horizon, but does not depend on wing beat frequency. A hypothesis is suggested that insect flapping flight power regulation system includes a finite number of stable kinematic patterns each corresponding to a particular flight mode and characterized by specific values of intimately correlated stroke parameters.
Доп.точки доступа:
GRODNITSKY, D.L.