Thursday, October 12, 2017
Dr. Simon Freeman
2:00 - 3:00 pm
Naval Research Lab
The internal propulsive structures of pelagic fishes have remained fundamentally unchanged for 530 million years, implying that their design is optimized for oscillatory locomotion underwater. Furthermore, the convergent evolution of soft mechanical features in large, high-performance, migratory elasmobranchs (sharks) and teleosts (bony fish) suggests a 'best solution' in terms of speed and efficiency for fast oscillating platforms of similar size. Recent advances in 3D printing, rapid prototyping and the understanding of hydrodynamics associated with oscillating propulsors have opened the door to bio-inspired vehicles that closely replicate the internal mechanics of specialized, speed-optimized ocean migrators such as the King Mackerel (Scomberomorus cavalla) and wahoo (Acanthocybium solandri). Dielectric Elastomer Actuator (DEA) technology has advanced sufficiently to replicate the performance of linearly contractile musculature, with the caveat that strains remain less than approximately ten percent. In this talk I will describe my current work at NRL: Analysis of the mechanical structures inside large, high-performance pelagic fishes for application in bio-inspired, soft-bodied UUV designs.
Dr. Simon E. Freeman is an Oceanographer at the U.S. Naval Research Laboratory (NRL) in Washington, D.C. He obtained undergraduate degrees in marine science and mechanical engineering at the University of Auckland, New Zealand, before moving to the U.S. to complete his Ph.D (2013) at Scripps Institution of Oceanography, San Diego. Simon's most recent project involves the development of acoustically stealthy, soft robotic unmanned underwater platforms. Simon's interests include soft robotics, pelagic biology, underwater acoustics, signal processing and coral reef ecology.