Using his National Science Foundation CAREER award, Dennis Hong of mechanical engineering is designing a Whole Skin Locomotion (WSL) mechanism to work on much the same principle as the pseudopod - or cytoplasmic "foot" - of the amoeba. Its unique mobility makes WSL the ideal locomotion method for search-and-rescue robots that need to travel over or under rubble. The mechanism also has the potential for use in medical applications - such as robotic endoscopes, for example...
If the engineering students at Virginia Tech are a litmus test for the success of autonomous systems research, this emerging strength in the Virginia Center for Autonomous Systems (VaCAS) at the university illustrates its national leadership in this crucial 21st century technology. VaCAS faculty members advise student teams and perform basic research in vehicle autonomy.
Examples of student success abound. In fall 2007, a team of Virginia Tech engineering and geography students won third place and $500,000 in the Defense Advanced Research Projects Agency (DARPA) Urban Challenge. Tony Tether, director of DARPA, was particularly complimentary of the Virginia Tech entry, according to Charles Reinholtz, one of the engineering faculty advisors for the project and who has since left the University.
And whereas it was reported that second place winner Carnegie Mellon spent some $5 to $6 million on its driverless vehicle, and that the first place entry from Stanford was also in this heavily financed realm, Virginia Tech’s team accomplished almost the same results and spent only $1 million. The team did have support from engineering alumni of its robotics program who formed a company called TORC Technologies LLC, located at the university’s Corporate Research Center. VaCAS members Al Wicks and Dennis Hong, faculty in the mechanical engineering department, also served as advisors in addition to Reinholtz.
This 2007 effort followed a strong showing in the 2005 DARPA competition. In 2005, a Virginia Tech team comprising only undergraduate and graduate students built and fielded two entries, “Cliff” and “Rocky.” These vehicles out-performed all other vehicles that were developed without significant corporate involvement. Fielding two entries in the competition was an extraordinary accomplishment — only 40 of the original 195 entries from around the nation (including many entries from private industry) survived the first phase of competition.
In a different international autonomous event, the Intelligent Ground Vehicles Competition, Virginia Tech has a strong tradition of dominating the awards, placing first in 2007, 2006, and 2005. In 2004, the team placed best overall and won six of nine categories, and was the only group from the U.S. to place in any category. The team also won the competition in 2000 and in 1998. Visit www.igvc.org/results.htm for all team results in this cutting-edge, multidisciplinary competition that encompasses the latest technologies of autonomous systems.
Displaying their talents in yet another worldwide contest, the Virginia Tech Aerial Robotics Team entered the International Aerial Robotics Competition. In 2006, its initial year as a contestant, the team won first place overall honors for its computer-controlled Bergen helicopter. And Virginia Tech was the only U.S. university to have a student team compete in the 2007 RoboCup Humanoid Division Soccer Tournament in Atlanta, Ga. Hong, a robotics expert, also advised this team.
Virginia Tech students have accepted the challenge of developing not only autonomous ground and air vehicles, but also autonomous underwater vehicles (AUVs). Virginia Tech’s AUV team participates in an annual engineering design competition aimed at expanding the ability of AUVs to sense and make decisions in unknown or changing environments. This team is co-advised by VaCAS members Dan Stilwell, an associate professor of electrical and computer engineering (ECE), and Craig Woolsey, an associate professor of aerospace and ocean engineering (AOE).
The success of Virginia Tech’s student design teams in autonomous vehicle research is attributable, in part, to the breadth and depth of the faculty expertise in unmanned systems. During the past decade, the interdisciplinary cooperation of faculty with interest in this topic led to the formation of VaCAS, with six core faculty and some two dozen affiliates, representing 11 departments in three colleges. Woolsey currently serves as the inaugural director of VaCAS.
Both Woolsey and Stillwell are recipients of prestigious NSF Faculty Early Career Development Program (CAREER) Awards, as well as the Office of Naval Research (ONR) Young Investigator Program Award to support and enhance their early research efforts. Hong has also received the NSF CAREER Award.
Woolsey’s CAREER and ONR awards provided him with initial funding to study the design of advanced controls and control mechanisms for unmanned vehicles. Woolsey is developing nonlinear control theory to improve the maneuverability, robustness, and reliability of underwater, air, and space vehicles. One application, of immediate interest to the Navy, involves the use of a streamlined underwater vehicle to survey underwater mine fields.
Stilwell used his CAREER and ONR awards to develop a fleet of miniature underwater vehicles that enable scientists to gather environmental data in areas such as the coast of Virginia, the Chesapeake Bay, and the Gulf of Mexico. Stilwell's objectives include the development of a low-cost miniature AUV, development of a mathematical theory to describe how AUVs can cooperate, and deployment of a fleet of vehicles to gather environmental data that would otherwise be impossible to collect.
Using his CAREER award, Hong is designing a Whole Skin Locomotion (WSL) mechanism to work on much the same principle as the pseudopod — or cytoplasmic “foot” — of the amoeba. With its elongated cylindrical shape and expanding and contracting actuator rings, the WSL can turn itself inside out in a single continuous motion, mimicking the motion of the cytoplasmic tube that an amoeba uses for propulsion.
“Our preliminary experiments show that a robot using the WSL mechanism can easily squeeze between obstacles or under a collapsed ceiling,” Hong says. “This unique mobility makes WSL the ideal locomotion method for search-and-rescue robots that need to travel over or under rubble. The mechanism also has the potential for use in medical applications — such as robotic endoscopes, for example, where a robot must maneuver in tight spaces.”
In the Nonlinear Systems Laboratory (NSL), a facility for research and instruction in control of nonlinear systems, Woolsey and his colleagues have developed a fleet of unmanned aerial vehicles (UAVs) to demonstrate such applications as vision-based flight control and flight vehicle coordination. One of these UAVs was used, together with an unmanned surface vehicle developed by Stilwell and the “Rocky” vehicle from the DARPA Grand Challenge, to successfully demonstrate autonomous riverine reconnaissance operations at the ONR-sponsored AUVFest in Panama City, Fla., in 2007. This effort was a close collaboration with colleagues at the Naval Postgraduate School in Monterey, Calif.
VaCAS was formally established in fall 2006, with financial support from Virginia Tech’s Institute for Critical Technology and Applied Science. The center capitalizes on more than a decade of work in various aspects of autonomous systems research.