home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Space & Astronomy
/
Space and Astronomy (October 1993).iso
/
mac
/
TEXT
/
STATION
/
STF_EVA.TXT
< prev
next >
Wrap
Text File
|
1992-09-09
|
3KB
|
64 lines
EVA RETRIEVER FACT SHEET
Johnson Space Center (JSC)
March 25, 1988
The EVA Retriever concept is an autonomous free flying robot
for retrieving equipment or a spacewalking astronaut drifting in
separated flight near the Space Station. The device combines the
proven manned maneuvering unit (MMU) with a robot latched in
where an astronaut normally would be. The MMU was flown eight
times from the Space Shuttle's cargo bay in test flights and for
satellite repair spacewalks.
Responding to voice commands from the Space Station crew,
the EVA Retriever would activate and check itself out, search for
and lock onto the "target," thrust toward, rendezvous with and
grapple the target -- automatically avoiding any obstacles en
route such as Space Station structures. After grappling the
target, the EVA Retriever would search for the Space Station and
finding it, return home.
A ground-based prototype of the EVA Retriever is under
development at JSC. The project has just completed the first
year of a 2-year program.
Television tracking and laser radar ranging signals are used
by "smart" software in an onboard computer to plan and command
search and rendezvous maneuvers in a simple environment without
obstacles. Robotic arms and hands are used to grapple the target
when in range.
The developmental EVA Retriever currently is using nine
words of a 200-word vocabulary to which it responds: activate
and quick-activate, search (tool, astronaut, home), rendezvous,
reach (extend arm with open hand), grapple (close hand), manual
(allows operator to modify Retriever's automatic sequencing),
wait and shutdown. Not only does the EVA Retriever carry out the
commands it hears but it also acknowledges those commands with a
human voice.
In JSC ground tests, the EVA Retriever is "flown" in two
dimensions on a 3-thousandths-inch layer of compressed air on the
Precision Air-Bearing Floor.
If the EVA Retriever is approved and funded for space
operations, the device first would be tested from Space Shuttle's
cargo bay before signing on for permanent employment aboard the
Space Station in the 1990's.
The EVA Retriever is a joint development of the JSC Tracking
and Communications Division, Crew and Thermal Systems Division,
Systems Development and Simulation Division and Avionic Systems
Division.
Industry participants in the EVA Retriever development
are: Martin Marietta Aerospace, MMU; Odetics, 3-D imaging laser
radar; McDonnell Douglas Astronautics Co., video tracking system;
Inmos Corp., central computer; Votan, voice control system;
Remote Technology Corp., robot arms/hands; and JSC (in house),
software, retriever body and hands.
- end -