Smart Software "Learns" Precise Docking
DOCKING ONE SPACECRAFT
WITH ANOTHER will be much easier, thanks to smart computer software
being developed at NASA's Ames Research Center. The neural net software
will "learn" the motion behavior of a spacecraft as it
flies, so it will not undershoot or overshoot docking targets.
The Ames "neurocontroller" will be able to automatically
dock a spacecraft of unknown mass with another by flying the spacecraft
short distances in different directions and learning the handling
characteristics of the craft, according to Dr. Robert W. Mah, an
Ames research scientist. "The neurocontroller automatically
enables precise, safe docking. This software learns similar to the
way human beings learnby experience, handling the spacecraft,"
Mah said. The neural net software used in the controller is similar
to that used to automatically focus home camcorders.
"Current methods used to dock spacecraft will be improved
to make docking easier for astronauts," Mah said. "Docking
a spacecraft by manual joystick control depends on the skill of
Manual docking can be slower than desired, and in some cases precious
fuel can be wasted. Conventional software has been used to automatically
dock spacecraft, when the spacecraft mass properties are known,
according to Mah. "But conventional automated docking doesn't
work well when the exact mass is unknown or changing robot arm positions
alter spacecraft flight characteristics," Mah said.
A future "worker bee" spacecraft, which would be used
during construction in space, might grab a construction part and
rotate, Mah said. "The arm and the part held by the spacecraft
have a tendency to keep rotating," he added. In contrast, the
same spacecraft equipped with the neurocontroller would immediately
learn the new "feel" of the way the spacecraft rotates
in space while firing its impulse jets. The smart software would
then precisely slow the spacecraft's rotation by "burning"
the jets for just the right amount of time.
The Ames neurocontroller has not yet been tested in space. "We
hope to do space tests eventually, but first we need to fine-tune
the software in the lab, making more realistic simulations with
test vehicles floating on a cushion of air over a special granite
table," Mah concluded.
The neural net software is a form of artificial intelligence.
It can be used in the medical field for neurosurgery and for breast
and prostate cancer surgery to identify tissues and tumors with
less damage. The software has the ability to "learn" the
characteristics of a system or different kinds of tissues, such
as brain or tumor tissue. In the aircraft industry, neural net software
could be used to safely land damaged planes and could be an effective
tool for the next generation of flight controllers.
For more information, contact Dr. Robert Mah at Ames Research
Call: 650/604-6044, Fax: 650/604-3594, E-mail: email@example.com
Please mention you read about it in Innovation.
net software programs that are smart enough to "learn"
the way humans learn may automatically dock spacecraft more precisely