Å®ÉúСÊÓƵ

When astronauts travel to Mars, they may be able to explore the planet
without leaving the safety of their spacecraft. NASA is developing control
systems for robots which allow the operator to see, hear and even feel what
the robot is experiencing but from a safe distance. NASA will test a prototype
submersible using this technology, known as telepresence, in October in
Lake Hoare in Antarctica.

The operator of the submersible will wear a headset similar to those
used in virtual reality systems. The headset has a small television screen
in front of each eye. It responds to the movement of the wearer’s head which
moves the submersible’s cameras accordingly.

Simpler forms of telepresence have been in use for several years. Robert
Ballard of the Woods Hole Oceanographic Institution in Massachusetts explored
the wreck of the Titanic with submersibles controlled by operators sitting
in front of television monitors using joysticks. Technology being developed
by the US military goes a step further and tracks the position of the operator’s
eyeballs to simulate real vision more exactly.

NASA’s submersible will supplement the operator’s vision with a spectroscopic
system developed by SETS Technology, a company based in Hawaii. The system
views the scene around the submersible and analyses the spectrum of visible
and infrared light reflected from objects the robot is looking at. According
to Tom McCord, chief scientist at SETS, the robot will eventually be able
to compare the spectra of objects it is looking at with templates stored
in its memory to identify the objects.

Future versions of NASA’s telepresence system will pick up objects and
convey their weight and texture back to the operator. Butler Hine, leader
of the intelligent mechanisms group at NASA’s Ames Research Center in California,
says that a student at Stanford University has designed a prototype glove
that gives the wearer the impression of feeling the mass of an object. The
glove contains an alloy which expands and contracts when different electric
currents pass through it.

NASA is also studying a device for conveying texture. It was designed
for Braille readers: an image recognition system reads ordinary print and
then uses an array of retractable points to convey Braille letters to a
blind person’s fingertips. NASA uses an optical sensor to analyse light
scattering on the object’s surface to determine its texture. It then conveys
the information to the fingertip device where the array of points simulate
the texture. Other possibilities include acoustic sensors that will convey
the feeling of tapping on a surface.