07-07-2012, 04:27 PM
space robotics
space robotics.pdf (Size: 1.02 MB / Downloads: 170)
WHAT IS SPACE ROBOTICS?
Space robotics is the development of general purpose machines that are capable of surviving (for a time, at
least) the rigors of the space environment, and performing exploration, assembly, construction, maintenance,
servicing or other tasks that may or may not have been fully understood at the time of the design of the robot.
Humans control space robots from either a “local” control console (e.g. with essentially zero speed-of-light
delay, as in the case of the Space Shuttle robot arm (Figure 3.1) controlled by astronauts inside the
pressurized cabin) or “remotely” (e.g. with non-negligible speed-of-light delays, as in the case of the Mars
Exploration Rovers (Figure 3.2) controlled from human operators on Earth). Space robots are generally
designed to do multiple tasks, including unanticipated tasks, within a broad sphere of competence (e.g.
payload deployment, retrieval, or inspection; planetary exploration).
ISSUES IN SPACE ROBOTICS
How are Space Robots created and used? What technology for space robotics needs to be developed?
There are four key issues in Space Robotics. These are Mobility—moving quickly and accurately between
two points without collisions and without putting the robots, astronauts, or any part of the worksite at risk,
Manipulation—using arms and hands to contact worksite elements safely, quickly, and accurately without
accidentally contacting unintended objects or imparting excessive forces beyond those needed for the task,
Time Delay—allowing a distant human to effectively command the robot to do useful work, and Extreme
Environments—operating despite intense heat or cold, ionizing radiation, hard vacuum, corrosive
atmospheres, very fine dust, etc.
INTERNATIONAL EFFORTS IN SPACE ROBOTICS
Other nations have not been idle in developing space robotics. Many recognize that robotic systems offer
extreme advantages over alternative approaches to certain space missions. Figures 3.32–33 show a series of
images of the Japanese ETS-VII (the seventh of the Engineering Technology Satellites), which demonstrated
in a flight in 1999 a number of advanced robotic capabilities in space. ETS-VII consisted of two satellites
named “Chaser” and “Target.” Each satellite was separated in space after launching and a rendezvous
docking experiment was conducted twice, where the Chaser satellite was automatically controlled and the
Target was being remotely piloted. In addition, there were multiple space robot manipulation experiments
which included manipulation of small parts and propellant replenishment by using the robot arms installed on
the Chaser.
THE STATE-OF-THE-ART IN SPACE ROBOTICS
The current state-of-the-art in “flown” space robotics is defined by MER, the Canadian Shuttle and Station
arms, the German DLR experiment Rotex (1993) and the experimental arm ROKVISS on the Station right
now, and the Japanese experiment ETS-VII (1999). A number of systems are waiting to fly on the Space
Station, such as the Canadian Special Purpose Dexterous Manipulator (SPDM, Figure 3.43) and the Japanese
Main Arm and Small Fine Arm (SFA, Figure 3.44). Investments in R&D for space robotics worldwide have
been greatly reduced in the past decade as compared to the decade before that; the drop in the U.S. has been
greater than in Japan or Germany. Programs such as the NASA Mars Technology Program (MTP) and
Astrobiology Science and Technology for Exploring Planets (ASTEP), as well as the recent NASA
Exploration Systems Research and Technology (ESRT) programs represent an exception to the generally low
level of investment over the past decade. However, some or all of these programs are expected to be scaled
back as NASA seeks to make funds available to pursue the Vision for Space Exploration of the moon and
Mars. Figure 3.45 shows an artist conception of a Robonaut-derived vehicle analogous to the mythical
ancient Greek Centaurs, with the upper body of a human for sensing and manipulation, but with the lower
body of a rover for mobility. Figure 3.46 shows a comparison between the first two autonomous planetary
rovers flown, Sojourner (or actually the flight spare, Marie Curie) and Spirit.
space robotics.pdf (Size: 1.02 MB / Downloads: 170)
WHAT IS SPACE ROBOTICS?
Space robotics is the development of general purpose machines that are capable of surviving (for a time, at
least) the rigors of the space environment, and performing exploration, assembly, construction, maintenance,
servicing or other tasks that may or may not have been fully understood at the time of the design of the robot.
Humans control space robots from either a “local” control console (e.g. with essentially zero speed-of-light
delay, as in the case of the Space Shuttle robot arm (Figure 3.1) controlled by astronauts inside the
pressurized cabin) or “remotely” (e.g. with non-negligible speed-of-light delays, as in the case of the Mars
Exploration Rovers (Figure 3.2) controlled from human operators on Earth). Space robots are generally
designed to do multiple tasks, including unanticipated tasks, within a broad sphere of competence (e.g.
payload deployment, retrieval, or inspection; planetary exploration).
ISSUES IN SPACE ROBOTICS
How are Space Robots created and used? What technology for space robotics needs to be developed?
There are four key issues in Space Robotics. These are Mobility—moving quickly and accurately between
two points without collisions and without putting the robots, astronauts, or any part of the worksite at risk,
Manipulation—using arms and hands to contact worksite elements safely, quickly, and accurately without
accidentally contacting unintended objects or imparting excessive forces beyond those needed for the task,
Time Delay—allowing a distant human to effectively command the robot to do useful work, and Extreme
Environments—operating despite intense heat or cold, ionizing radiation, hard vacuum, corrosive
atmospheres, very fine dust, etc.
INTERNATIONAL EFFORTS IN SPACE ROBOTICS
Other nations have not been idle in developing space robotics. Many recognize that robotic systems offer
extreme advantages over alternative approaches to certain space missions. Figures 3.32–33 show a series of
images of the Japanese ETS-VII (the seventh of the Engineering Technology Satellites), which demonstrated
in a flight in 1999 a number of advanced robotic capabilities in space. ETS-VII consisted of two satellites
named “Chaser” and “Target.” Each satellite was separated in space after launching and a rendezvous
docking experiment was conducted twice, where the Chaser satellite was automatically controlled and the
Target was being remotely piloted. In addition, there were multiple space robot manipulation experiments
which included manipulation of small parts and propellant replenishment by using the robot arms installed on
the Chaser.
THE STATE-OF-THE-ART IN SPACE ROBOTICS
The current state-of-the-art in “flown” space robotics is defined by MER, the Canadian Shuttle and Station
arms, the German DLR experiment Rotex (1993) and the experimental arm ROKVISS on the Station right
now, and the Japanese experiment ETS-VII (1999). A number of systems are waiting to fly on the Space
Station, such as the Canadian Special Purpose Dexterous Manipulator (SPDM, Figure 3.43) and the Japanese
Main Arm and Small Fine Arm (SFA, Figure 3.44). Investments in R&D for space robotics worldwide have
been greatly reduced in the past decade as compared to the decade before that; the drop in the U.S. has been
greater than in Japan or Germany. Programs such as the NASA Mars Technology Program (MTP) and
Astrobiology Science and Technology for Exploring Planets (ASTEP), as well as the recent NASA
Exploration Systems Research and Technology (ESRT) programs represent an exception to the generally low
level of investment over the past decade. However, some or all of these programs are expected to be scaled
back as NASA seeks to make funds available to pursue the Vision for Space Exploration of the moon and
Mars. Figure 3.45 shows an artist conception of a Robonaut-derived vehicle analogous to the mythical
ancient Greek Centaurs, with the upper body of a human for sensing and manipulation, but with the lower
body of a rover for mobility. Figure 3.46 shows a comparison between the first two autonomous planetary
rovers flown, Sojourner (or actually the flight spare, Marie Curie) and Spirit.