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ATTLEBORO - Once while scuba diving, Tom Bliss tried following an eagle ray.

He was "amazed how the graceful flapping of its wings propelled the animal at incredible speeds."

Now Bliss, a 2001 graduate of Attleboro High School, is on a team building a robotic version of a manta ray, a "close relative" to the eagle ray.

Bliss, 26, is doing his research at the University of Virginia, where he hopes to earn a Ph.D. in mechanical engineering in 2010. "The manta ray robot could be used to monitor marine life and reef growth, as it is a non-invasive platform," explains Bliss, who played soccer and tennis and participated in student government at Attleboro High.

"It could also see use in structure monitoring of oil rigs or ship hulls, or even payload deployment and reconnaissance.

Aside from the manta ray itself, the advancements we are making in the areas of structures and controls could also be applied to terrestrial and aerial robots."

Bliss recently received a scholarship, for the third year, from the Achievement Rewards for College Scientists Foundation, which, on its Web site, describes itself as "a national volunteer women's organization dedicated to helping the best and brightest U.S. graduate and undergraduate students by providing scholarships in natural sciences, medicine and engineering. The Foundation was formed in 1958 in Los Angeles in response to Sputnik and the lack of U.S. supremacy in the technology race."

This interview was conducted by e-mail.

SUN CHRONICLE: Robotic manta rays have been in the works for years. How is the one you're working on different?

TOM BLISS: I will begin by saying that the portion of research I am conducting is a part of the manta ray project encompassing many aspects of engineering, from structural foundation to hydrodynamics and computational fluid dynamics.

With this large scope, our project differentiates itself from prior attempts at robotic rays through an interdisciplinary approach, aiming to build a robot capable of efficient cruise and also high maneuverability.

More specifically, two aspects of the project that I am working on are the structures and controls that form the foundation for the robot.

The structures we are using are called tensegrities, which are comprised of a system of bars held in compression by a network of cables in tension (you can think of two crossed bars, tie all the ends with string, and when you pull the string tight, the structure forms a rigid rectangle, like a simple kite). We can obtain shape changes of this type of structure by changing the lengths of the bars, or in our case, pulling on the cables. To obtain swimming motions, we must coordinate which strings to pull and how far to pull them.

By looking at nature for inspiration, we are synthesizing the neurons that coordinate rhythmic motions in animals, such as the flapping of a fishtail or the swinging of a leg.

When properly designed, these neuronal circuits are capable of finding the structure's most efficient motions, or gaits if you will.

SC: How did your project come about?

BLISS: As I mentioned, my work is only part of the larger project as a whole.

My specific area of focus actually spawned from discussions between myself and two of my professors at U.Va.

One professor's area of expertise is structures, and the other's is controls, specifically the neural control I mentioned. Through some brainstorming sessions, we decided to combine the two disciplines, and my project was born.

SC: What are some of the engineering challenges of developing one?

BLISS: There are many challenges in our project.

First, the goal is not simply building a prototype, but rather developing the methods, theories and techniques to be used to build a robust autonomous underwater vehicle.

Therefore, there are mathematical and analytical challenges, material selection challenges and even testing challenges.

We want to make sure that the methods and theories we develop are accurate, and therefore we have to build test rigs to validate our findings, which is often easier said than done.

SC: What's your favorite part of your work?

BLISS: My favorite aspect of my work are the challenges I just mentioned.

The work we are doing is novel, so there is no road map to follow to reach our goals. We are in the process of drawing that map, building the knowledge base that others will use in the future.

As with most research, there are many failures on the way, whether it be crashing computer code or tests that break or do not work altogether. So each success, no matter how small, is rewarding.

SC: What drew you to mechanical engineering?

BLISS: I have always been interested in math and science, physics in particular.

After high school, I decided to pursue an engineering degree and focused on mechanical engineering in particular due to my interest in cars and jets. Although I do not currently work in those disciplines, the methods used in engineering, and their physical foundations, are shared among the fields.

SC: What's your long-term dream as an engineer?

BLISS: I am currently undecided in what to do after my doctoral program, whether to stay in academia or enter industry.

Either way, I envision working on research and development projects, exploring new control technology and structural foundations.

I really enjoy working on robotic applications of these disciplines, and could see myself staying in this field, as we are trying to replace personnel with robots in high risk environments.