Autonomous robot
An autonomous robot is
a robot that performs behaviors or tasks with
a high degree of autonomy, which is particularly desirable in
fields such as space exploration, cleaning floors, mowing
lawns, waste water treatment and delivering goods and services.
Some modern factory robots are "autonomous" within the
strict confines of their direct environment. It may not be that every degree of
freedom exists in
their surrounding environment, but the factory robot's workplace is challenging
and can often contain chaotic, unpredicted variables. The exact orientation and
position of the next object of work and (in the more advanced factories) even
the type of object and the required task must be determined. This can vary
unpredictably (at least from the robot's point of view).
One important area of robotics research is to enable the
robot to cope with its environment whether this be on land, underwater, in the
air, underground, or in space.
A fully autonomous robot can[
·
Gain information about the environment (Rule #1)
·
Work for an extended period without human intervention
(Rule #2)
·
Move either all or part of itself throughout its
operating environment without human assistance (Rule #3)
·
Avoid situations
that are harmful to people, property, or itself unless those are
part of its design specifications (Rule #4)
An autonomous robot may also learn or gain new knowledge
like adjusting for new methods of accomplishing its tasks or adapting to
changing surroundings.
Like other machines, autonomous robots still require
regular maintenance.
Contents
Examples[
Self-maintenance
The first requirement for complete physical autonomy is
the ability for a robot to take care of itself. Many of the battery-powered
robots on the market today can find and connect to a charging station, and some
toys like Sony's Aibo are capable of self-docking to charge
their batteries.
Robot GUI
display showing battery voltage and other proprioceptive data in lower
right-hand corner. The display is for user information only. Autonomous robots
monitor and respond toproprioceptive sensors without human intervention to
keep themselves safe and operating properly.
Sensing the
environment
Exteroception is sensing things about the environment.
Autonomous robots must have a range of environmental sensors to perform their
task and stay out of trouble.
·
Common exteroceptive sensors include the electromagnetic
spectrum, sound,
touch, chemical (smell, odor),
temperature, range to various objects, and altitude.
Some robotic lawn mowers will adapt their programming by
detecting the speed in which grass grows as needed to maintain a perfectly cut
lawn, and some vacuum cleaning robots have dirt detectors that sense how much
dirt is being picked up and use this information to tell them to stay in one
area longer.
Task
performance
The next step in autonomous behavior is to actually
perform a physical task. A new area showing commercial promise is domestic
robots, with a flood of small vacuuming robots beginning with iRobot and Electrolux in
2002. While the level of intelligence is not high in these systems, they
navigate over wide areas and pilot in tight situations around homes using
contact and non-contact sensors. Both of these robots use proprietary
algorithms to increase coverage over simple random bounce.
The next level of autonomous task performance requires a
robot to perform conditional tasks. For instance, security robots can be
programmed to detect intruders and respond in a particular way depending upon
where the intruder is.
For a robot to associate behaviors with a place
(localization) requires it to know where it is and to be able to navigate
point-to-point. Such navigation began with wire-guidance in the 1970s and
progressed in the early 2000s to beacon-based triangulation. Current commercial robots
autonomously navigate based on sensing natural features. The first commercial
robots to achieve this were Pyxus' HelpMate hospital robot and the CyberMotion
guard robot, both designed by robotics pioneers in the 1980s. These robots
originally used manually created CAD floor plans, sonar sensing and
wall-following variations to navigate buildings. The next generation, such as
MobileRobots' PatrolBot and
autonomous wheelchair,[1] both introduced in 2004, have the ability
to create their own laser-based maps of a building and to navigate open areas
as well as corridors. Their control sy
stem changes its path on the fly if
something blocks the way.
At first, autonomous navigation was based on planar
sensors, such as laser range-finders, that can only sense at one level. The
most advanced systems now fuse information from various sensors for both
localization (position) and navigation. Systems such as Motivity can rely on
different sensors in different areas, depending upon which provides the most reliable
data at the time, and can re-map a building autonomously.
Rather than climb stairs, which requires highly
specialized hardware, most indoor robots navigate handicapped-accessible areas,
controlling elevators, and electronic doors.[2]With such electronic access-control
interfaces, robots can now freely navigate indoors. Autonomously climbing
stairs and opening doors manually are topics of research at the current time.
As these indoor techniques continue to develop, vacuuming
robots will gain the ability to clean a specific user-specified room or a whole
floor. Security robots will be able to cooperatively surround intruders and cut
off exits. These advances also bring concomitant protections: robots' internal
maps typically permit "forbidden areas" to be defined to prevent
robots from autonomously entering certain regions.
Outdoor autonomy is most easily achieved in the air,
since obstacles are rare. Cruise missiles are rather dangerous highly autonomous
robots. Pilotless drone aircraft are increasingly used for reconnaissance. Some
of these unmanned aerial
vehicles (UAVs) are
capable of flying their entire mission without any human interaction at all
except possibly for the landing where a person intervenes using radio remote
control. Some drones are capable of safe, automatic landings, however. An
autonomous ship was announced in 2014—the Autonomous
spaceport drone ship—and is scheduled to make its first operational
test in December 2014.[3]
·
Three-dimensional terrain
·
Great disparities in surface density
·
Weather exigencies
·
Instability of the sensed environment
In the United States, the MDARS project, which defined
and built a prototype outdoor surveillance robot in the 1990s, is now moving
into production and will be implemented in 2006. The General Dynamics MDARS
robot can navigate semi-autonomously and detect intruders, using the MRHA
software architecture planned for all unmanned military vehicles. The Seekur
robot was the first commercially available robot to demonstrate MDARS-like capabilities
for general use by airports, utility plants, corrections facilities and Homeland Security.
The Mars rovers MER-A and MER-B (now known as Spirit rover and Opportunity rover) can find the position of
the sun and navigate their own routes to destinations on the fly by:
·
Mapping the surface with 3D vision
·
Computing safe and unsafe areas on the surface within that
field of vision
·
Computing optimal paths across the safe area towards the
desired destination
·
Driving along the calculated route;
·
Repeating this cycle until either the destination is
reached, or there is no known path to the destination
The planned ESA Rover, ExoMars Rover, is capable of
vision based relative localisation and absolute localisation to autonomously
navigate safe and efficient trajectorys to targets by:
·
Reconstructing 3D models of the terrain surrounding the
Rover using a pair of stereo cameras
·
Determining safe and unsafe areas of the terrain and the
general "difficulty" for the Rover to navigate the terrain
·
Computing efficient paths across the safe area towards
the desired destination
·
Driving the Rover along the planned path
·
Building up a navigation map of all previous navigation
data
The DARPA Grand Challenge and DARPA Urban Challenge have encouraged development of even
more autonomous capabilities for ground vehicles, while this has been the
demonstrated goal for aerial robots since 1990 as part of the AUVSI International
Aerial Robotics Competition.
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