Fish may be key to
innovative
engineering
By Matt Clifford
Contributing Writer
With a puckered face and a square, yellow body splattered with small black dots, the subject of Assistant Professor of Biological Sciences Jeff Walker’s submarine development research appears a haphazard concoction of tropical fish and a pottery experiment gone terribly awry.
Watching this small, square fish – appropriately called a boxfish – swim in circles inside a six-inch PVC pipe does not immediately reveal why it is suitable for scientific research. But seeing it maneuver from a stationary hover to executing a full 360-degree turn on its axis starts to make things clear.
Walker is on the beginning leg of a three-year research project that may lead to a new propulsion and stabilization system for U.S. Naval submarines. Walker, who has been at USM for one year, is studying the unique swimming mechanics of the boxfish.
Boxfish, which have rigid bodies because of their fused scales, cannot swim like most fish–by oscillating their bodies and tails side-to-side. They rely on their pectoral fins on the sides of their bodies to propel them through the water. With this unusual configuration, the boxfish has greater maneuverability and stability than most other species. The fish can steadily hover, even in its turbulent coral habitat, and has the ability to turn full circle on its axis.
Walker is studying this specialized swimming technique and will give his findings to the United States Navy. Walker says the Navy hopes to “use features of the boxfish that would seem desirable to implement in an AUV” or Automated Underwater Vehicle, a small unmanned submarine. The new design will likely take on varied missions such as combing the ocean floor for search and recovery, mine defusing, or as a surveying instrument.
This new technology will hopefully replace conventional AUVs, which lack the necessary stability and maneuverability necessary to operate efficiently in the high turbulence and swift currents of shallow, tidal waters.
In addition to the boxfish, Walker is studying several species of fish and the unique evolutionary characteristics each has gained. By identifying general standards of fish’s swimming performance and strength, he will be able to establish a baseline level of performance by which to compare machines. He hopes then that his findings can be blended together to form a unique array of specialized capabilities in one machine.
Walker, whose prime interest is body shape diversity and evolution, studies animals ranging from beetles to snails to fish.
“The performance of human engineered vehicles is inferior to real animal performance,” he says.
By studying body shape diversity, Walker says it may be possible to engineer machines that match or exceed animal performance.
By taking on this and other research projects for the Office of Naval Research and the National Science Foundation, Walker is bringing new equipment and technologies into USM and the Biological Sciences Department. These resources will continue to serve the University after his current projects are complete. He is collaborating with Chair and Associate Professor of Biological Sciences Ken Weber and will use his equipment, namely a high-speed digital camera and analyzing software, to study fruit fly flight. Walker says that his equipment could serve other departments as well, including sports medicine, by recording and analyzing human locomotion.
Walker’s work is also benefiting the University by giving students hands-on training and experience in biological research.
Contributing Writer Matt Clifford
can be contacted at