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A New Way to See the World
UCLA Researchers Create Low-power Vision Sensors for Embedded Networks
Cyclops is a low-power image sensor platform. |
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Vision is among the most powerful ways we have to sense the world
around us. However, because of excessive power demands, embedded
sensor networks have been unable thus far to leverage imaging to
monitor an environment in detail.
In such a system, large numbers of inexpensive sensor nodes could
be deployed to detect and reveal information about the environment,
including the presence of an intruder in a secure area, movements
of people on public transit, or changes in the natural environment.
Modern camera-equipped sensors, although very small and capable
of producing very high quality images, can require a great deal
of energy to operate.
Mohammad Rahimi, a researcher in the Center for Embedded Networked
Sensing, computer science professor Deborah Estrin, and electrical
engineering professors Mani Srivastava and John Villasenor are investigating
a number of energy-aware networked image sensor platforms and applications.
One such platform, Cyclops, bridges the gap between commercial cameras
and sensor network capabilities.
“The model we are using is common to embedded sensing: deploying
a large number of small devices operating at small data rates,”
explains Srivastava. “Cyclops uses a low-complexity vision sensor
capable of tracking variations in light, shape, number, or color
while limiting power demands on the network.”
A team of engineers and scientists in the UCLA Henry Samueli School
of Engineering and Applied Science has created Cyclops, a tiny platform
that attaches to Mica motes, which are commonly used as nodes in
wireless sensor networks. The researchers adapted small cameras
similar to those used in cell phones, and developed the circuitry
and software that enables the nodes to process the images in context
and report any new information. UCLA is partnering with Agilent
who has expertise in manufacturing small, integrated cameras to
create the Cyclops platform.
“Local intelligence on board the individual motes enables them to
notify only for specific events,” says Srivastava. “The image sensor
collects information, processes it on site, and then sends the relevant
information in response to queries from users on the network.”
Villasenor’s team are applying their experience in image processing
to develop reliable, inexpensive vision systems designed to use
as little energy as possible, making them ideal for embedded networks.
“We’re also interested in the question of how much can be done locally
vs. how much processing is done elsewhere,” says Villasenor. “Should
the nodes process the images and only ship the end data, which takes
very little energy to send but requires very sophisticated image
processing on site? Or should they ship the image, which requires
more bandwidth but less processing on the sensor itself?”
To limit power requirements for the system and make it sustainable
over time, the UCLA researchers have reduced the resolution of the
images captured by the motes to approximately 160-by-160 pixels.
Shaun Ahmadian, David Zats, and Mohammad
Rahimi with a Cyclops system. |
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“We don’t need perfect images to gather useful data,” says Rahimi,
“just enough to detect key elements in the environment. We can make
up for any loss in quality by having multiple cameras in a single
area, providing multiple perspectives of objects and individuals
in a given space.”
In addition the imaging sensors, the Cyclops system includes a central
computer which manages queries from users and reports the network
results, and a database that tracks permanent environmental context
information. Like other projects in the Center for Embedded Networked
Sensing (CENS), all of the tools they have developed are open source.
Shaun Ahmadian, David Zats, and Juan Garcia, computer science undergraduate
students, helped to develop Cyclops’ application software, and participated
in a test deployment in which they tracked traffic patterns and
movement in a constrained area.
The UCLA research group plans to develop a full testbed, deploying
60 Cyclops units in the Mildred E. Mathias Botanical Garden on campus.
The local, outdoor setting will allow the team to easily test new
algorithms, database behavior, and network activity under realistic
conditions.
“We’re also working on several possible applications for Cyclops,”
says Rahimi, “smart environments and biological studies. A system
using infrared cameras would alert researchers in CENS when birds
are detected in nest boxes at the James San Jacinto Mountains Reserve,
and help them track population changes. The infrared sensors would
compensate for the low-light conditions without disturbing the birds.”
When fully developed, imaging systems based on platforms such as
Cyclops could be applied to a range of applications, including monitoring
of traffic flow on public transportation systems, securing sensitive
military areas, or tracking the way in which individuals move through
an exhibit at a museum.
For media inquiries, please contact Melissa Abraham (mabraham@support.ucla.edu
or 310/206-0540.)
- Marlys Amundson
01.11.06
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