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9
Robotics, Automation, and Artificial Intelligence
BACKGROUND AND STATUS
In 1987, the National Research Council report Space Technology to Meet Future
Needs stated that "the time has come to add a new technology, automation and robotics,
to the other major technologies propulsion and power, materials, and information
management that are considered essential to U.S. capability to operate effectively in
space. There are three reasons: affordability, achievability, and need" (NRC, 19871.
Since that report, the technology is no longer "new." Much has been done, but it is still
young relative to other space technologies. However, the reasons for its application are
becoming even stronger.
The application of automation and robotics to NASA's mission is in a state of
transition. NASA is increasingly moving toward the use of small spacecraft and
associated systems and technology that may minimize the need for robot-assisted
servicing. At the same time, the servicing and maintenance of major projects such as the
Hubble Space Telescope and the Space Station are being planned using teleoperated
robotic arms.
This section is directed toward the following applications for robotics, automation,
ant} artificial intelligence as they relate to small spacecraft applications that the pane!
believes offer great potential payoffs:
small microrovers capable of rapid deployment and numerous operations,
for robotic exploration of Mars; and
small robotic spacecraft and intravehicular robotics, which can contribute
to crew productivity and the health and maintenance of major space assets
such as the Space Station and the Hubble Space Telescope.
In addition, the pane! believes that increased applications of computer-based
systems will benefit all aspects of mission operations, including training and simulations.
These systems are discussed in Chapter 2 of this report.
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Robotics, Automation, and Artificial Intelligence
SMALL ROBOTIC PLANETARY EXPLORERS
In the area of planetary exploration, small spacecraft systems are already being
developed. For example, the NASA Mars Pathfinder project scheduled for launch in
1996 will employ an innovative microrover (termed "Rocky") operating in the vicinity
of a Mars landing craft. This craft serves as a science base and as the communications
center with Earth. With the ability to operate somewhat autonomously in the vicinity of
the lander craft, Rocky can significantly increase the total returned knowledge. The Mars
Pathfinder baseline is for remote task control, where an Earth-based operator can observe
the three-dimensional environment of Rocky and program in the next sequence of
maneuvers.
Rocky's perceptive ability is based on a laser line-striping scanner. However, its
task-control ability is limited by an 8-bit processor and the associates} limited memory.
Rocky has sensors for operation as well as limited spectral-analysis capability for rock
samples.
The potential for limiter! autonomous operation after the completion of the
principal mission objectives is being considered for Mars Pathfinder. However, there is
concern that the microrovers will prove to be limited in overall performance due to
technological deficiencies identified in this report.
The NASA Mars Pathfinder project is the focal point for all on-going rover
technology development. Currently, fully autonomous rovers for future missions are
being developed, but due to limited resources, the work has not reached a stage of
maturity where it can confidently be included in the next flight project. Technology for
autonomous mobility exists at various locations, including several NASA Centers
ARPA, and Carnegie Mellon University.
Overall, the development of small automated science instruments and of
m~cromanipulators with capabilities similar to Flight Telerobotic Servicer-cIass systems
and suitable for use in small rovers is lagging behind the rest of the spacecraft systems.
Small, capable stereo-vision systems do not exist. Unless technology advances are macle,
the capability of future, proposed programs such as the Mars Surveyor program
consisting of orbiters, ground stations, and microrovers, will be limited by the inability
of the rovers to perform important exploration tasks, such as sample collection'
preparation, and even limited analysis.
Major enhancements in the ability of microrovers can be made by investing in the
development of small calibrated science instruments and small robotic manipulators
capable of extended operations and improved analytical skills on the planets. Fully
autonomous microrovers capable of independent exploration and reporting could turn a
network of small rovers into a powerful research tool. This would minimize the impact
of the time delay between the Earth and Mars on mission planning and scientific results.
The ultimate long-term success of these remote explorers will result from the aggressive
application of autonomous operation in an unstructured environment.
Since current rover designs use solar arrays to generate power, the ability to fully
implement a truly productive, planetary microrover exploration system is now directly
related to the amount of sunlight available at the planet to be explored. For the Mars
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Technology for Small Spacecraft
Pathfinder program, the limited power available to Rocky from its solar power generation
system seriously limits its effectiveness, especially at higher latitudes of Mars. In the
future, lightweight, low-cost radioisotope power systems could be enabling technologies
for planetary exploration with microrovers. Other technology developments recommended
throughout this report, such as miniaturized guidance and control and communication
components; high-capacity, lightweight computers; and advanced materials and
structures, could also contribute to the effectiveness of these small robotic spacecraft.
One way to achieve planetary surface technology development objectives in the
near term while accomplishing significant scientific objectives, would be to conduct
experimental work on the surface of the moon. This could be done with much shorter
flight times than those required to travel to Mars, provide higher solar power, and permit
greatly expanded communications.
SMALL ROBOTS IN LOW EARTH ORBIT
The Space Station is a major investment in space infrastructure, in which a limited
number of humans must be provided with systems that will help improve their efficiency.
The proper application of automation and robotics can improve the return on this
investment by freeing the crew from repetitious tasks and allowing for more direct
involvement of ground-based researchers in mission execution via teleoperations. Within
the research environment of the Space Shuttle and the Space Station, small intravehicular
activity robots such as the German ROTEX on the 1993 Space Laboratory mission can
turn a limited flight opportunity into a productive research project. The automation of
human-tended teleoperatec! space-based investigations is within the technical capability
of university and industry investigators. To date only the Germans have demonstrated its
utility in space.
Small robotic spacecraft could reduce, and in some cases eliminate, the need for
extravehicular activity and ShuttIe-related operations. In the vicinity of the Space Station,
small, free-flying robots could be programmed for autonomous or teleoperated inspection
of critical Space Station systems as an integral part of repair and maintenance. The
concepts and technology base exist within NASA, the universities, ant! industry to
develop autonomous systems that are efficient and fault-tolerant with respect to human
safety needs. These new, small space robots can become unique, relatively Tow-cost tools
for the crews of the Space Station, and they could help bring research productivity more
in line with earlier (1980) expectations involving larger crew complements.
Perception research is needler} for recognizing robot tasks ant! positioning,
controlling, ant! safeguarding devices used in extravehicular and intravehicular activities.
Task-contro! research to achieve robotic competence via task-control techniques, task
diagnostics, and fault recovery strategies should be conducted. In abolition, research on
mechanical systems is needed to create miniaturized, low-power, reliable robot
components and complete servicing robots. Finally, flight opportunities to evolve
competent servicing robots should be made available. Several NASA centers, including
Ames Research Center, GSFC, JPL, and the Johnson Space Center, are working on task
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Robotics, Automation, and Artificial Intelligence
control techniques such as robot task planners, sequence safeguards, user displays, and
interfaces. Much progress has been made in this area since the 1987 National Research
Council report (NRC, 1987~.
Small, robotic free flyers capable of performing autonomous, as well as
teleoperated, inspection and maintenance are being researched at the University of
Maryland, Johnson Space Center, and JPL. The only project with a planned launch is the
University of Maryland's Ranger Robot, which is not scheduled to interact with a
manned spacecraft during its flight. Such robotic systems employ single-string designs
and software. The integration of autonomous inspection and maintenance into the manned
program has not occurred. Work to date is limited to concepts and laboratory
demonstrations.
Initiating the required research and development now could make systems
available for insertion incrementally during the projected 10-year life of the Space
Station.
OTHER AGENCY PROGRAMS
Beyond NASA, there is much automation and robotic work supported by DOE,
DoD, ARPA, BMDO, the National Science Foundation, and industry. For the most part,
these programs are focused on point solutions for repetitive problems such as
manufacturing or hazardous-waste cleanup, rather than on changing tasks and space
environments that are characteristic of most NASA applications. ARPA is supporting an
unmanned ground vehicle development for teleoperated and autonomous vehicle
navigation for the U.S. Army and U.S. Marine Corps. The current support of space-
based automation and robotics research and development is almost entirely funcled by
NASA. Much of this development can apply to small space systems.
FINDINGS AND PRIORITIZED RECOMMENDATIONS
Recommendations for NASA technology development for spacecraft subsystems
that are also applicable to small robotic spacecraft are addressed in other sections of this
report. The recommendations included here apply to technologies specific to small
robotic spacecraft or peculiar to the robotic technology.
Technology work related to autonomous operations in unstructured
environments should be supported and expanded.
2. Autonomous systems and artificial intelligence should be developed for
application to microrovers.
~ A research and development program focused on miniaturizing robotic
devices, science instruments, and associated computing power should be developed.
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Technology for Small Spacecraft
4. Robotic spacecraft systems incorporating the most advanced autonomous
systems and artificial intelligence technology currently available should be developed for
demonstration in space on small spacecraft and on the Space Shuttle. The technology
should be applied to the development of a free-flying robotic spacecraft for inspection,
maintenance, and research support on the Space Station.
Beyond the NASA-unique advantages, the continued investment in automation,
artificial intelligence, and robotics is in the broader national interest. Such systems have
already changed the way we work and how goods are manufactured.
Representative terms from entire chapter:
robotic spacecraft
