A beastly air problem of mammoth proportions
ho are you going to call when you need to balance the air
conditioning needs of a 42-foot long dinosaur, people-eating lions,
Somalian wild asses, a pair of elephants and thousands of museum
visitors and staff?
Chicago's Field Museum of Natural History hired Associate Professor
Doug Reindl (left) and Professor Sanford Klein (right) to study the
heating, ventilation, humidity and air conditioning systems in their
massive, century-old structure. Reindl summarized the challenge: "How
are we managing to destroy in a few decades artifacts that have lasted
hundreds of years? And how can we prevent that? We can either put
artifacts in a secure, safe environment and keep people out or we can
compromise and put them in a display where people can see them."
Their work was further complicated by the fact that 95 percent of the
museum's collections are in storage. These collections must be
preserved while remaining accessible to scientists.
Reindl, Klein and graduate student Janeen Ault set up monitors
throughout the building to collect a year's worth of information on
the building's climate. They also researched the heating, ventilation
and air-conditioning systems used by other museums. The team's
recommendations include replacing seals on exterior emergency doors,
relocating thermostats to more representative locations, demolishing a
wall restricting air movement from one exhibit hall to another, and
adding humidifying equipment.
Klein and Reindl also recommended reducing intake of outside air. A
significant amount of damaging air pollution comes from nearby Chicago
traffic and parking lots. Contaminants from auto exhaust react
chemically with the artifacts causing irreversible damage.
Improving the safety of automobiles--one joint at a time
Automobile manufacturers strive to improve the quality and safety
standards of cars with every new model. Through her work in laser
materials processing and intelligent manufacturing, Assistant
Professor Elizabeth Smith is contributing to that effort by making the
welded joints in automobiles and other products stronger and safer.
Lasers provide a precise, flexible source of intense energy for
materials processing applications such as welding, cutting, forming
and heat-treating. Smith uses small microphones to monitor the
acoustic signals generated during the laser welding process. With this
approach, she can identify the quality of the laser-welded joints and
identify defects that may not have been found otherwise.
Smith's interest in intelligent manufacturing is not limited to
industrial laser applications. Manufacturing operations, in general,
can be made more robust and reliable through the integration of
monitoring systems. Sensors can be applied for real-time process
control of both traditional and non-traditional manufacturing
operations. For example, acoustic signals can be used to monitor
machining operations like turning and milling.
Smith's research in laser materials processing extends beyond
automotive applications, encompassing electronics manufacturing and
novel microfabrication techniques, with applications in
microelectromechanical systems, biomedical devices and more.
Strength and efficiency through flexibility
Elastic deformation is generally considered undesirable in the design
of conventional rigid-link mechanisms which rely on rigid members and
localized joints to translate forces and motions. Assistant Professor
Joel Hetrick is working with compliant mechanisms: structures which
utilize elastic deformation to emulate the behavior of traditional
For applications requiring moderately small motions, compliant
mechanisms have many advantages over traditional devices, including
the elimination of friction, wear and backlash associated with
mechanical joints. In addition, the monolithic nature of compliant
mechanisms makes them easy to fabricate and can minimize or altogether
eliminate assembly requirements.
Hetrick recently created a novel micro-compliant displacement
multiplier for Sandia National Laboratories. When coupled with an
electrostatic actuator, the compliant displacement multiplier
efficiently amplifies the actuator displacement by a factor of 10,
while requiring one-fifth the chip area of a standard direct-drive
actuator. The new actuator-multiplier is being investigated for use in
a variety of MEMS applications which require high-speed, compact
Hetrick is now focused on automating design of compliant mechanism and
smart material systems. The combination of these systems could enable
a host of new devices including minimally invasive surgical tools,
better microfluidic pumps and valves, and faster, more efficient