ROBOT OPERATED MATERIAL PROCESSING IN SPACE (ROMPS) The ROMPS program is a space
shuttle-based materials processing experiment that uses SCL as its master
control system. The ROMPS software launched onboard Space Shuttle Discovery,
Mission STS-64 in September 1994.
MISSION The mission of ROMPS was
to demonstrate commercial methods of processing semiconductor materials
in a microgravity environment.
DESIGN The current robotic design
of ROMPS permits it to address a variety of commercial objectives in materials
processing and automation technology. ROMPS is designed to advance microgravity
processing by using a robot to transport each of a large variety of semiconductors
from the storage racks to halogen lamp furnaces where their crystal structures
are reformed in heating and cooling cycles.
THE FIRST ROMPS is the first U.S.
robotics system used in space. The autonomy afforded by the robotics was
essential to the success of the mission. Because movement would affect
the growth of the crystals and skew the experiment results, it was necessary
that the experiments be performed while the astronauts slept. The onboard-embedded
SCL system made decisions and controlled the robotic arm, processing more
than 200 semiconductor material samples. The eleven-day mission was 100%
successful. All of this while the astronauts slept.
SCL MADE THE DIFFERENCE The SCL system on-board
ROMPS flight hardware scheduled the processing activities and monitored
the health and welfare of the hardware, running on an 80286 based computer
onboard the vehicle onboard ROMPS flight hardware. At the ground station
in Goddard Space
Flight Center (GSFC), SCL ran on a distributed set of personal computers
network and monitored the progress of the experiment. Our customer for
this application was the Environmental Research
Institute of Michigan (ERIM) and GFSC.
WHAT’S NEXT The ROMPS samples were analyzed
on the ground after the shuttle mission, and the results were compared
to samples processed on Earth. These results will also be used to define
materials and processing for planned later flights of ROMPS on future shuttle
missions.
The ROMPS flight system was
derived largely from the previous efforts in developing the flight software
for the ARD program. The controller card, executive software, and SCL Real-Time
Engine will be reused from mission to mission. ICS also developed software
to communicate with the NASA Hitchhiker Interface.
OTHER OBJECTIVES A long-term objective of
ROMPS is to develop microgravity-processed semiconductor devices with sufficient
performance advantages that they can be produced competitively in space.
Another objective of the
ROMPS program is to advance automation and robotics for material processing
in ways that can lower the costs of developing and manufacturing semiconductors.
SCL advances this objective by using elements of commercial hardware and
software automation products that allow a direct “spin-off” to U.S. industry.
The added cost of operations
in space creates a need for in-space materials processing to have more
advanced automation and robotics to increase productivity. For example,
an efficient long term space facility for materials processing not only
needs to have robotic materials processing, but the assembly, servicing
and upgrading of the facility also needs to be done by robotics. SCL offers
a higher level of automation and robotics needed for in-space materials
processing that can be applied to improve the operational efficiencies
of ground-based semiconductor laboratories and production facilities.
A new proximity sensor, called
a Capaciflector, developed by Goddard, will be flown to aid in the alignment
of the pallets to within a thousandth of an inch. By using the electric
field generated by the sensors, proximity of the pallets to the furnace
aperture can be measured and perfect alignment can be made without physical
contact perturbing the process. Developing such a sensor-based control
scheme is key to advancing space automation and robotics.