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Robotic Surgery * Flying Over the River * Voices of Engineering * Improved Aerospace Worker Training * High Praise * Shake It
Robotic Surgery
For most people, robots are either futuristic or fanciful,
but researchers at North Carolina State University and East Carolina University
(ECU) see them as current, essential tools in the most basic of tasks
- life-saving surgery. Dr. Randolph Chitwood and Dr. Wiley Nifong, surgeons
at ECU's Brody School of Medicine, are among the first in the world to
perform state-of-the-art medical procedures using a remote-controlled,
two-armed robot. The surgeon sits across the room in a comfortable control
console and operates a set of joysticks that guide the robot's arms. Other
members of the surgical team assist at the patient's side with anesthesiology
and tool manipulation.
One surgical procedure being performed with this robot is minimally invasive mitral heart valve correction. Chitwood and Nifong have been performing this surgery the past few years using the da Vinci robotic system, which employs a unique robotic arm called the EndoWrist that provides the same dexterity as a human wrist. Major surgery can be performed with as few as three incisions, each the size of a quarter, rather than the open-chest incisions of days past. The surgeon experiences less fatigue, improved 3-D depth perception, and a realistic feel during the operation compared with standard endoscopic surgery. However, as with any new technology, problems arise that require innovative solutions.
Because ECU has no engineering school, surgeons and research physicians
there are working with NC State engineering faculty and students to solve
problems and expand the capabilities of robot-assisted surgery. For example,
last spring the ECU surgical team discovered that the wire tendons used
to actuate the robotic arm were failing after only 10 surgeries. Chitwood
and Nifong collaborated with Dr. Greg Buckner, assistant professor of
mechanical and aerospace engineering.
Jason Stevens, at the time an undergraduate mechanical and aerospace engineering
student at NC State, worked under Buckner's guidance to research this
problem as part of a special projects course. He determined that bending
fatigue in the wires was causing tendon failure.
Stevens is continuing his studies at NC State as a master's student with
Buckner. Together they're looking toward the future of minimally invasive
robot-assisted surgery. "We see micro-scale robotics as a promising
avenue for research," says Buckner. "Instead of a massive, externally-actuated
robot, micro-scale robots could be actuated from within the chest cavity."
Instead of an immense million-dollar machine like da Vinci, which occupies
about 20 square feet of floor space, micro robots would be the size and
shape of a six-legged beetle and could be disposable. Currently if the
da Vinci system breaks down, the surgeon must finish the operation by
hand; with micro robots, dozens of spares could be kept in stock and simply
exchanged if one failed during surgery. "Best of all, surgery with
micro robots is the least invasive surgery imaginable. These robots could
be so tiny that all their work would be performed inside the patient's
body."
Stevens' challenge is to develop a functional micro robot using miniature actuation techniques. Motors and gears are impractical for such a small device, so he must use artificial muscles that contract and expand under the influence of electrical fields or chemical gradients. To do this, he is experimenting with various materials, including shape memory alloys and polymer gels. According to Buckner, "There are whole families of new materials that have the potential to do the same things human muscles do." To start, Stevens hopes to develop a ten-scale prototype robot to demonstrate advanced actuation technologies. Eventually he would like to develop a semi-autonomous, truly miniature robot to perform a simple surgical task. "Once developed, this robot could be used for a wide range of applications, such as gripping, cutting, sensing and positioning," says Stevens.
Flying Over the River
An engineer and surveyor from Rettew Associates, a multi-discipline
engineering and environmental consulting firm based in Lancaster, Pennsylvania,
recently flew by helicopter over the West Branch of the Susquehanna River
in north central Pennsylvania to map the waterway. They generated a detailed
map for use by conservation groups and students, according to a report
in the Daily Item newspaper. The study of 75 miles of the Susquehanna
was conducted by the Northcentral Pennsylvania Conservancy and funded
by a Growing Greener grant from the state's Department of Conservation
and Natural Resources.
Flying over the river at about 1700 feet at speeds of 85 to 90 mph, a digital video camera attached to the bottom of the helicopter recorded detailed pictures. Pilot Jerry Ehrhart and Ed Warfel, director of surveying for Rettew, observed a monitor in the cockpit as the camera linked with Global Positioning Satellite information that labels each frame with latitude and longitude coordinates. The information was then processed into a Geographic Information System, which allows viewing of the area.
The detailed mapping allows preservation groups like the conservancy to run simulations of different plans for preventing erosion or encouraging plant or animal growth. Information will also be available to students studying the ecosystem or planning a preservation Project. The conservancy plans to develop a greenway plan, which includes features such as riverside trails.
Voices of Engineering
The American Association of Engineering Societies (AAES), in
conjunction with the United Engineering Foundation and NASA, is sponsoring
Voices of Innovation, a new public radio program that celebrates and explores
the world of engineering by introducing listeners to the people who transform
imagination and ingenuity into technological wonders. According to the
program's website, "In just two minutes, this daily short-format
program will key into the passion, excitement, and genius that inspires
the men and women who make technological miracles a part of our everyday
experience. We hope that your encounter with Voices of Innovation fosters
a greater recognition of the essential role engineers play in society."
AAES undertakes a wide spectrum of public awareness activities to improve
public knowledge of engineering.
Some 300 public radio stations worldwide broadcast the series. Sample episodes tell how new technology created a prosthetic hand so responsive it can play the piano and how engineers are working to minimize structural damage from earthquakes. Another one invites you to join NASA's only female pilot on the SR-71 at three times the speed of sound. A fourth one asks, "Can you guess what handy invention debuted on a pair of galoshes? The Zipper." Producers are seeking leads for possible stories. To hear sample episodes and submit story ideas, visit www.voicesof innovation.org.
Improved Aerospace Worker Training
The Center for Advanced Engineering Environments (CAEE) at
Old Dominion University recently received a $2 million NASA Langley Research
Center grant, under which the university will lead a prestigious group
of schools such as MIT and the University of Illinois Champaign/Urbana
to enhance aerospace workforce training through a coupling of leading-edge
technologies. Dr. Ahmed Noor, CAEE director and eminent scholar of aerospace
engineering, will lead the consortium of seven universities, which also
includes Cornell, Syracuse, and George Mason Universities and the University
of Florida. The consortium will be headquartered at CAEE.
According to Noor, the aerospace industry faces a shortage of qualified workers with adequate skills, which current education and training doesn't address because it's fragmented and concentrates on near-term product development. The consortium will use a variety of technologies to develop advanced and unique learning systems that will link NASA, other government agencies, universities, industry, and technology providers in a network. By using high-productivity computing, modeling and simulation, interrogative visualization, intelligent human-computer interfaces, high-capacity communications, and networking and information technologies, the group will be able to conduct research and teach courses without the constrictions of geography.
"This network will stimulate critical thinking and intelligent growth
and promote intermingling among emerging and traditional engineering and
science disciplines," Noor says. "It will create a new generation
of engineers who can work across disciplines and perform in rapidly changing
environments. It will also enable collective intelligence, innovation,
and creativity to bear on the increasing complexity of future aerospace
systems."
High Praise
The Consulting Engineers Council of Maryland has awarded Henry
Adams, Inc., a Baltimore engineering firm, its Grand Award in the 2002
Engineering Excellence Awards competition for the design of the mechanical
and electrical systems in the Clarice Smith Performing Arts Center at
the University of Maryland, College Park. The highly praised arts and
education center was created through a partnership of the design team,
the University, the State of Maryland, and Prince Georges County.
University officials and community representatives commissioned the facility to be a world class arts and education center with breathtaking architecture, an inviting atmosphere, and superb acoustical character. At the same time, the facility was to be cost-effective and responsive to modern codes for energy efficiency, indoor air quality, and occupant comfort. The challenge was to integrate a complicated air conditioning system into the complex architecture while maintaining stringent acoustical criteria with minimal mechanical equipment noise and draft-free air distribution.
This involved designing quiet HVAC systems within 10 linked structures that form one building. Different HVAC systems were developed to conform to each performance space. Acoustic ductwork, sound muffling devices, and efficient low-speed fans contribute to quiet air distribution. Engineers created a cost-efficient design using recovered heat from exhaust air, variable volume air supply, and energy-conserving equipment.
Precise planning and discipline coordination were required to fit the equipment around the special rigging of the theaters within the center, the 20 wet-pipe sprinkler zones, and duct work layout in multi-level spaces, which ranged from nine to over 100 feet high.
Shake It
The University at Buffalo's Department of Civil, Structural,
and Environmental Engineering has been awarded $16.5 million to develop
the world's most versatile earthquake engineering research facility, says
a story in Engineering Times. The new facility will provide testing capabilities
that will revolutionize the understanding of how structures behave during
earthquakes. It will feature the only shake table in the world that can
be repositioned easily, as well as the only earthquake engineering lab
capable of conducting real-time seismic hybrid testing. The latter is
a form of testing being pioneered by UB researchers that breaks new ground
in earthquake engineering research. In these tests, shake table experiments
and computer simulations are combined in real time to provide the most
complete picture possible of how powerful earthquakes affect buildings,
bridges, and other structures.
The research facility, which will receive funding from the National Science Foundation and state governments, will house twin shake tables capable of testing structures up to 120 feet long. Other features include an upgrade of the existing shake table so it will move in six different directions, new actuators that provide a total capacity of 1.7 million pounds of force, and high-definition television equipment to transmit physical and computational results to other engineering labs.
Progressive
Engineer
Editor: Tom Gibson
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