Design of Bio-Structural View on Micro Aerial Vehicles of Practical Flyer

Abstract

We can learn many things by observing the biological flight of insects, birds and bats since they fly with higher aerodynamic efficiency i.e., their lift to drag ratio is much higher as compared to our airplanes. They produce thrust by a complex morpho-functional flapping phenomenon. The comparison of flight features of these three types of fliers gives us some useful clues on the nature of natural wing materials having special properties (like light weight and high flexibility) which must be considered seriously for their usage in Micro aerial vehicle to enhance their aerodynamic efficiency. The evolutionary history of these fliers and flapping is a notable feature. Insects are miniature fliers having low mass, resilin, and membranous chitinous wings, with high flapping frequency of 500 Hz or more. To imitate them is difficult. Birds and bat wings are modified tetrapod limbs for flight. Birds have thousands of keratin feathers which cannot be replicated easily. In birds, the finger bones are reduced. However, in bats, the finger bones are highly elongated (delicately) and the whole body is covered by membrane. It may be easier to imitate bat model and not its echo location. Anti stalling devices (.4lula in birds) need further study. Their effortless landing and take-off are notable for micro aerial vehicle design. Comparative moment of inertia studies gives better aerodynamic information on biological wings. These natural fliers have extraordinary sensory perception, integration, feedback mechanism and adaptive control of flight. The researchers are trying to suggest how to incorporate some of these features in micro aerial vehicle designs. In fact, in the most advanced fighter aircrafts (like F - 22 Rap tor of USA) some sensory features are incorporated. We can think of flexible materials for wings, like silk, thin graphite with latex support etc. The biological wings are elastic, and they withstand bending and damp the vibrations.