In the same way that the launch of Yuri Gagarin in April 1961 announced the beginning of human space flight, last year's flight of the German ROTEX robot flight experiment is heralding the start of a new era of space robotics. After a gap of twelve years since the introduction of a new capability in space remote manipulation, ROTEX is the first of at least ten new robotic systems and experiments which will fly before the year 2000

Lavery, Dave

Weisbin, Charles

English

NASA Technical Reports Server

The Next Decade of Space Robotics
Dave Lavery
Telerobotics Program Manager
Office of Advanced Concepts and Technology
National Aeronautics and Space Administration
Washington, DC 20546
dave.lavery@hq.nasa.gov
te1:202-358-4684
fax: 202-358-2697
Charles Weisbin
Telerobotics Project Manager
Jet Propulsion Laboratory
Pasadena, CA 91109
charles r weisbin@ccmail.jpl.nasa.gov
N95. 23673
KEY WORDS AND PHRASES
Robotics applications, robotic exploration,
robotic servicing, space robotics
ABSTRACT
In the same way that the launch of Yuri
Gagarin in April 1961 announced the beginning
of human space flight, last year' s flight of the
German ROTEX robot flight experiment is
heralding the start of a new era of space
robotics. After a gap of twelve years since the
introduction of a new capability in space remote
manipulation, ROTEX is the first of at least ten
new robotic systems and experiments which
will fly before the year 2000.
Biting Off Too Much
Historically, the space robotics community has
pursued the goal of creating fully autonomous,
self-contained robotic systems with
considerable onboard intelligence as the next
major objective in space robotics evolution.
Systems such as the Flight Telerobotic Servicer
(FTS) were intended to provide near-human
levels of intelligence and dexterity, capable of
interpreting very high level command structures
and autonomously executing the commands
without human intervention. The robot was
designed to replace a full-time human operator
with automated sensing, perception, planning
and reasoning sufficient to conduct daily
operations.
Since the initiation of the FTS and similar
ambitious undertakings, the robotics
community has gained new understanding of
the research still required to create the
technologies needed for such systems.
A New Focus
While the technology to support fully
autonomous intelligent robotics is not yet
available, operational needs for capable remote
manipulation and locomotion still exist. In the
space robotics arena, a significant paradigm
shift is taking place to contend with these
needs. Rather than attempting to force the use
of immature technology to emulate the "smarts"
of a local astronaut operator, the new focus is
to utilize advanced teleoperation technology to
move the operator from close proximity on-
orbit to the ground. Technology elements
including predictive displays, low-level reactive
planners, sensor-based command execution
and dynamic world modeling enable the ability
to contend with problems associated with
relocation of the operator, such as time-delayed
communications, limited viewing options and
limited command stream bandwidth. While
there is still a long-term goal of developing
intelligent autonomy for robots, the short-term
goal has become the development of
technology to push forward "intelligent
teleoperation."
The major impact of this shift in development
philosophy is the new opportunity to move
robotics out of the laboratory and into the field.
The maturation of advanced teleoperation
technologies has helped increase confidence in
https://ntrs.nasa.gov/search.jsp?R=19950017253 2020-06-16T08:46:26+00:00Z
Space Robotics Applications Timeline
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the ability of robotic systems to robustly
perform real tasks. With this increased
confidence has come the acceptance of the
potential benefits offered by space robotics
technology, and the challenge to "fly it and
prove it" with a series of robotic flight
experiments and demonstrations. The new
push to "get things flying" will yield multiple
new space robotic systems before the end of
the 1990's.
Robotic systems to be flown during the next
five years fall into three categories: Extra-
Vehicular Robotic (EVR) servicers, science
payload servicers, and planetary rovers.
EVR Servicers
The EVR servicer systems are robotic systems
deployed in Earth orbit for use outside of
pressurized, controlled environments. Such
systems are typified by the Shuttle RMS,
which was first flown on the STS-2 mission is
1981. Target applications for these systems
include on-orbit satellite assembly,
maintenance, repair and servicing, robotic
enhancement of Shuttle payload bay
operations, and ground-control robotic
servicing of external Space Station payloads.
Canada is providing two space robots for use
on the International Space Station. The Space
Station Remote Manipulator System (SSRMS)
is a 55-foot long, 7-Degree Of Freedom (7-
DOF) manipulator similar to the Shuttle RMS.
Designed to maneuver and locate large
payloads along the Space Station truss
structure, the SSRMS can transfer power, data
and video signals from attached payloads via
the latching end effectors at both ends of the
arm.
The second Canadian system is the Special
Purpose Dexterous Manipulator (SPDM), a
dual-arm dexterous robotic system composed
of two 7-DOF manipulators, a Power-Data
Grapple Fixture, and supporting structures and
tooling. The SPDM is controlled during
teleoperations with two 3-DOF hand controllers
and via keyboard entry and/or preprogrammed
sequences for automated trajectory control.
Each manipulator is controlled separately, in
addition to independent control for the SPDM
body and the SSRMS (during operations where
the SPDM is positioned by the SSRMS).
At the same time, Japan is preparing a dual-
manipulator system as an element of the Space
Station Japanese Experiment Module (JEM).
Composed of the Main Arm and Small Fine
Arm, the JEM Remote Manipulator System
(JEMRMS) is intended to provide maintenance,
servicing and changeout of science packages
placed on the JEM exposed experiment carrier.
The Main Arm, similar in configuration to the
SRMS and SSRMS, is a 6-DOF positioning
tool used to transport large payloads and
provide coarse positioning for smaller, more
dexterous manipulators. The Small Fine Arm
is a 6-DOF manipulator which can be operated
either from the end of the Main Arm, or from a
fixture on the exposed experiment facility.
Under development by Martin-Marietta
Corporation and the NASA Johnson Space
Center, the Dexterous Orbiter Servicing System
(DOSS) is being developed to provide
dexterous manipulation capability for
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operations in the Space Shuttle payload bay.
The DOSS is a MPESS-mounted robot that can
operate from a fixed base or from the end of the
Shuttle RMS. The purpose of this 7-DOF
manipulator is to provide the Shuttle crew and
mission controllers with a tool to augment and
potentially replace selected EVA activities in the
payload bay. These activities include EVA
worksite setup, nominal and contingency
payload operations (ie. opening lens covers,
removing GAScan lids, etc.), and technology
development activities.
Ranger is being integrated at the University of
Maryland, under sponsorship of the NASA
Telerobotics Program. Scheduled for flight in
late 1996 aboard an expendable launch vehicle,
Ranger is a dual-arm free flying telerobotics
flight experiment which will conduct on-orbit
validation and verification of many of the
technologies developed by the NASA program.
Utilizing telepresence ground-based control,
coordinated manipulator operation, automated
rendezvous and docking technology, and a
hybrid propulsion system, Ranger will conduct
a simulated satellite servicing exercise to
characterize the operational capabilities of free-
flying robotic systems. The project will
correlate neutral buoyancy robotic simulations
by developing nearly identical underwater and
space flight units, and performing identical
tasks in both environments.
Japan is also developing a free-flying robotic
servicing experiment, scheduled for flight in
1997 aboard a H-II rocket. A target vehicle
and chase vehicle will be deployed to exercise
technologies including GPS receivers,
rendezvous radar, proximity CCD sensors,
docking mechanisms and onboard guidance
computers. Simultaneously, a 6-DOF
manipulator mounted on the chase vehicle will
be used to demonstrate cooperative control of
the chase vehicle attitude as it reacts to
manipulator position, ground-based
teleoperation of the manipulator, demonstration
of on-orbit satellite servicing including fuel
transfer and battery exchange, and target
vehicle acquisition, grappling and restraint.
Science Payload Servicing
Science payload servicing robotics differ from
the EVR systems in that they are designed to
maintain experiment payloads in controlled
environments, and are specifically designed as
elements of nominal experiment operations
(i.e., the robot is intended to be a functional
component of the overall experiment,
performing tasks such as reagent
replenishment, product harvesting, sample
collection, etc.), and not just as contingency
and repair systems in the event of experiment
failure or malfunction.
At least two such systems are currently in the
final stages of preflight integration.
McDonnell-Douglas has recently completed
development of Charlotte. Charlotte is a small
robot physically connected to it's work
environment with a series of eight Kevlar
strands. The strands extend from the corners
of the robot's rectangular body to hard points at
the extreme corners of the workspace, which
may be the interior of SpaceLab, SpaceHab or
a space station module. By increasing and
releasing tension on selected strands, the body
of the robot is able to translate throughout the
entire volume of the workspace.
The Robotic Operated Materials Processing
Systems (ROMPS) is a joint project between
the NASA Goddard Space Flight Center, the
Michigan Space Automation and Robotics
Center, and the Zymark Corporation. ROMPS
will demonstrate low-cost on-orbit processing
through the use of robotics to autonomously
produce semi-conductor materials. Scheduled
for launch on STS-64, this GAScan experiment
will investigate zero-gravity annealing of semi-
conductor thin films. The robot will utilize
low-level automation to maintain the materials
furnace, supply source substrates to the furnace
and harvest processed thin films.
The European Space Agency is investigating
the incorporation of a large-scale science
payload maintenance robot into the Columbus
module of Space Station. This system would
have a work envelope encompassing the entire
interior of the module, and would provide
logistics support for science experiments and
materials production systems.
Planetary Surface Systems
Planetary surface robotics is the area in which
the largest breadth of knowledge exists,
although it is somewhat dated. As early as
1967, the Surveyor missions carried simple
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remotely-operated manipulators to the surface
of the Moon to collect samples of the Lunar
regolith. Followed by the Russian Lunakhods
in 1969 and 1980, and the Viking missions to
Mars in 1976, these early efforts identified the
fundamental environmental constraints and
technology obstacles to be surmounted to
enable the development of robust, long-lived
planetary surface robotics.
It was traditionally accepted that the next
generation of robotic rovers for unmanned
Lunar and Mars missions would be large (800-
kg or more), monolithic, highly intelligent and
autonomous devices which would require
significant development and operational
support in terms of technology, budget,
computational and human resources. Then in
1989, a small group of rogue technologists at
MIT and JPL began a new initiative in micro-
rover technology based on subsumption
architectures. Making use of progressively
smaller computers, increasingly advanced
sensors, and maturing mobility systems, a
series of micro-rover testbeds was developed
which culminated in the MESUR (Mars
Environmental Survey) Pathfinder Rover. This
six-wheeled 5 kg-class rover is scheduled for
launch to Mars in 1996, and will perform
technology validation experiments in addition
to science investigations and instrument
deployment. Control for the rover will be
shared between Earth and the limited onboard
intelligence of the rover. By combining
sensory input with predefined "behaviors" the
rover will autonomously navigate between the
waypoints, avoiding rocks, crevasses and other
impassable terrain.
Scheduled for flight in 1998, Russia intends to
launch the Mars '98 mission which will include
the Marsokhod rover. Being developed by the
Institute for Space Research (IKI) and the
Babakin Center of NPO Lavochkin, the
Marsokhod is a six-wheeled, 100-kg rover that
will use radioisotopic thermal generators
(RTG) for power generation and thermal
control. Because of the RTGs, the rover will
be able to operate during the Martian night, and
is expected to have a long surface lifetime (one
year or more) with a potential total excursion
distance of over 100 kilometers. The
Marsokhod enables exceptional mobility
characteristics through the use of unique bi-
conic titanium wheels and a segmented three-
part chassis.
In addition to these Mars-bound rovers,
LunaCorp has announced plans for a lunar
rover project slated for launch in 1998. Rather
than driven by science needs, the incentive for
this project is primarily entertainment - the goal
of the project is to provide the world's first
interactive space exploration event by giving
the public the opportunity to drive the rover on
the moon. The rover will be remotely operated
via telepresence control from workstations
located in theme parks around the country.
Capitalizing on NASA rover technology
developments, LunaCorp is working with
Carnegie-Mellon University to transfer these
technologies into the first commercial lunar
rover application.
Technology Requirements for Future
Systems
With the advent of these new experimental and
operational space robotic systems, the ability
for remote manipulation to offer significant
improvements to mission operations, cost
effectiveness and mission safety will be
proven. But these will still be early generations
of advanced space robotic applications. As
successive waves of space robotic applications
are deployed beyond the year 2000, the goal of
intelligent, autonomous space robotics will
become more and more important. Technology
drivers for these systems include enhanced
collision detection and avoidance, advanced
local proximity sensing, task level control
workstations, improved command and control
architectures, fault tolerant architectures,
reduced mass and volume, worksite
recognition and representation, improved
robotic dexterity, advanced supervisory
control, and improved overall system
robustness.
By combining these next-generation
technologies with the operational knowledge
gained from applications being flown in the
next few years, the first intelligent space
robotic systems will be within reach. By then
combining the technologies with the
development procedures utilized by the current
suite of applications, the next generation of
space robotic applications will be affordable,
even within the ever-tightening budget
environment of today's space program.
12
ES ON CO
Commercialization
CO.1 A New Containerless Image Furnace with Electrostatic
Positioning Device
T. Yamawaki, NASDA, Tsukuba, Japan; C. Tsukishima, Mitsubishi Electric Corporation,
Amagasaki, Japan; T. Abe and A. Kaneko, Mitsubishi Electric Corporation, Kamakura, Japan
CO.2 Software Agents for the Dissemination of Remote Terrestrial
Sensing Data
15
C. N. Toomey, E. Simoudis, R. W. Johnson, and W. S. Mark, Lockheed Artificial Intelligence
Center, Palo Alto, California, USA
19
CO.3 Commercialization of JPL Virtual Reality Calibration and
Redundant Manipulator Control Technologies 23
W. S. Kim, H. Seraji, and P. Fiorini, JPL, California Institute of Technology, Pasadena, California,
USA; R. Brown, B. Christensen, and C. Beale, Deneb Robotics, Inc., Auburn Hills, Michigan,
USA; J. Karlen and P. Eismann, Robotics Research Corp., Amelia, Ohio, USA
.................._:._
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The next decade of space robotics

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