Perpustakaan Digital ITB

Flapping wing flight stands out as one of the most complex yet widespread modes of transportation found in nature. Over a million different species of insects fly with flapping wings, and 10,000 types of birds and bats flap their wings for locomotion. This proliferation of flying species has also attracted scientific attention. Biologists and naturalists have produced kinematic descriptions of flapping wing motion and empirical correlations between flapping frequency, weight, wingspan, and power requirements based on studies of many different families of birds and insects. Bio-fluiddynamicists have attempted to explain the underlying physical phenomena both in the quasi-steady limit and in the fully unsteady regime, and it has long been realized that steady-state aerodynamics does not accurately account for the forces produced by natural fliers, and this has prompted several studies on the unsteady flow produced. Mechanisms such as rotational circulation, wake capture, and the unsteady leading edge vortex do seem to properly account for the aerodynamics forces. The study about unsteady flow mechanism recently is developing faster and more accurate. Several great experiments of flapping wing robotics arm have a good result in quantifying this phenomenon. This experiment has a widely techniques to visualization the flow phenomenon of unsteady flapping wing. For example : Dickinson et al using DPIV system to quantifying the flow field, Liu et al using a smoke generator to visualize a Leading Edge Vortex (LEV), Ho et al using smoke wire visualization, etc. The other important key to understanding the flow phenomenon is to understand the wing kinematics it self, thus modeling a wing kinematics of flapping wing via a robotics arm is also must be considered well. In this research area, the unsteady flapping wing flow is choose to visualized by DPIV system, several experiment is done to follow the wing kinematics of insect flight in the towing tank. The flapping kinematics is analyze on the down-stroke with stroke angle is 90o, and furthermore, the aerodynamics forces is measure by using a momentum, flux, and impulse methods.