BIOLOGICALLY INSPIRED PROPULSOR
With funding from Office of Naval Research (ONR) Grant 341, I worked with a team of 3 talented students to develop a biologically inspired propulsive module using a structured product development process.
Our team designed tests, constructed testing apparatus, and implemented tests to characterize the flexural rigidity of composite materials with tuneable mechanical properties. We constructed mathematical and CAD models, as well as a physical proof-of-concept prototype to be used by researchers to investigate fin-based swimming.
The key advantage that fin-based swimming has over conventional propeller based locomotion is that it exhibits efficiency over a range of speeds. Flexible propulsors lend to further efficiency as they are able to produce force vectors that vary in magnitude and direction during the course of a single movement such that greater net thrust is produced along the desired trajectory. A propulsor whose stiffness can be actively modulated provides further advantage in controlling the manner in which vortices are shed. Since a flapping foil achieves maximum efficiency when operating at or near resonance, active stiffness modulation allows change of the mechanical properties of the propulsor such that it operates efficiently regardless of flapping frequency.