"The Nanomanipulator: a Virtual-Reality Interface to a Scanning Tunneling
Microscope",94 Imagina proceedings pp67-76
The Nanomanipulator system has been developed in collaboration by the Chemistry
department of the University of California at Los Angeles and the Physics and
Computer Science departments at the University of North California at Chapel Hill.
The goal of the Nanomanipulator system is to allow the scientist to interact
with a surface representation that matches as closely as possible the actual
surface itself. Towards this goal, the system provides an immersive virtual-world
interface to an STM. A head-mounted display shows a (blurry) stereo view of
the STM data drawn as if it were a surface floating in space in front of the
scientist. A force-feedback manipulator lets the user feel the height of the
surface; the STM tip follows the user's hand motion to sample the surface as
directed. Software control of the STM tip position, combined with control of
a pulse generator, allows the scientist to target areas on the surface for
change by moving his hand to the desired location and pressing a trigger.
Pulse magnitude and duration can be adjusted using dials on a virtual control
panel that floats in space near the user.
The Nanomanipulator has been used to explore surfaces and perform surface
modification experiments. When used to explore an ion-bombarded graphite
surface, the real-time shading and motion allowed the discovery of planes
of graphite that had become tilted up out of the surface. Prior visualization
of the same data set by other means had not revealed these features. The
interactive firing of pulses and immediate display of results enabled a
series of experiments that revealed a new type of tip-sample interaction
during pulses. It was discovered that often a wire forms between the tip
and sample after a pulse, and that the feedback then pulls the tip back
until the wire is broken.
The key features of the system is that it gives the scientist presence and
real-time control during the course of an experiment, placing him on the
surface in control while things are happening. Using the system, the scientist
can interactively (but as yet imperfectly) change the surface. The advantage
of using the Nanomanipulator in this process is that the scientist can detect
any mistakes or aberrations in the structure being built and correct them
in real time. A skilled user can respond to surprise much more creatively
than a computer algorithm, and when sculpting at the atomic scale, there
are bound to be many surprises.
Some external links :
Some more Comments :
All of the pictures and video of this project are copyright UNC.
They have their own Web page for the project.See the URL in the related WWW adresses.