In the popular imagination, the term robot evokes images of a
mechanical device that looks and acts like a human being. This type of
robot, called a humanoid or android, is common in science fiction
literature and cinema. In reality, the term robot can be applied
to any of a wide range of programmable machines, the common feature of
which is that they are capable of movement and can be used to perform
physical tasks. Robots are built in many different forms, ranging from
humanoid to industrial, and their appearance is dictated by the
functions they are to perform. They are usefully engaged in industrial
production requiring repetitive tasks, and in performing tasks that may
be difficult or dangerous for humans.
Several concerns have been
expressed about robots. One is that they can displace people from their
jobs. Another is that humanoid robots, if they acquire intelligence and
emotions that allow them to think and act on their own, may become
hostile toward humans and threaten humankind. The latter concern,
however, is based on fictional concepts. Real-world robots are machines
with their own mechanical limitations, and they lack the human spirit.
Although they may be built to simulate human intelligence and
decision-making traits to some extent, these abilities are governed by
artificially programmed feedback loops, not by creative thought
processes, heartfelt feelings, and senses of responsibility—qualities
that underlie human aspirations and freedom of expression. Consequently,
the abilities, activities, and value of robots will remain distinct
from those of humans.
What is a robot?
A robot
is a machine that can perform preprogrammed physical tasks. Robots have
been built to serve various functions, and they therefore appear in a
variety of forms. Some robotic devices, such as the robotic arm of the
space shuttle, act under direct human control. Other robots act
autonomously, under the control of a computer.
Certain robots,
such as remotely controlled bomb-disposal units, are used to perform
tasks that are too dangerous or difficult for humans to engage in
directly. Others, including those used in automobile production, have
made it possible to automate repetitive tasks, lowering the cost of
performing them.
Some robots may act according to their own
decision-making ability, provided by the technology of artificial
intelligence. Such robots include feedback loops such that they can
interact with and respond to their environment. They do not, however,
display actual intelligence.
Robots in history
The
idea of mechanical men and semi-intelligent mechanical devices
stretches back to the legends of ancient civilizations. For instance, in
classical Roman and Greek mythology, the god of fire and metalwork
(Vulcan in Rome and Hephaestus in Greece) created mechanical servants
ranging from intelligent, golden handmaidens to three-legged tables that
moved about under their own power. Jewish legend tells of the Golem, a
clay statue animated by Kabbalistic magic. Similarly, Norse mythology
(in the Younger Edda) tells of a clay giant, Mökkurkálfi or Mistcalf, constructed to aid the troll Hrungnir in a duel with Thor, the god of thunder.
One
of the first recorded designs of a humanoid robot was made by Leonardo
da Vinci around 1495. Da Vinci's notebooks, rediscovered in the 1950s,
contain detailed drawings of a mechanical knight that can sit up, wave
its arms, and move its head and jaw. The design is thought to be based
on his anatomical research recorded in the Vitruvian Man. It is not known whether he attempted to build the robot.
In
1737, French engineer Jacques de Vaucanson made the first known
functioning humanoid robot that played the tabor and pipe. He also made a
mechanical duck that reportedly had more than 400 moving parts and
could flap its wings, eat grain, drink, and defecate.
Nikola
Tesla invented a teleoperated boat, similar to a modern remotely
operated vehicle (ROV), that was demonstrated at an 1898 exhibition in
Madison Square Garden. Based on his patent for "teleautomation," he
hoped to develop the "wireless torpedo" into an automated weapon system
for the U.S. Navy.
Between 1937 and 1938, Westinghouse made eight
similar humanoid robots nicknamed Elektro, exhibited at the 1939 and
1940 World's Fairs. Each of these robots was about seven feet tall,
weighed 300 pounds, and could walk, talk (using a 78-rpm record player),
smoke cigarettes, and move its head and arms.
In 1948 and 1949,
W. Grey Walter at Bristol University, England, created the first
electronic autonomous robots, named Elmer and Elsie. They were often
described as tortoises, based on their shape and slow movements. These
three-wheeled robots were capable of phototaxis (movement guided by the
influence of light), by which they could find their way to a recharging
station when they ran low on battery power.
Robots in literature
Robots have been frequently used as characters in works of literature. The word robot first appeared in the play R.U.R. (Rossum's Universal Robots),
written by Czech writer Karel Čapek in 1920. In a short letter, Karel
Čapek credited his brother, painter and writer Josef Čapek, for having
coined the term robot. It is derived from robota, which means "compulsory labor" or "corvée" in the Czech language and "work" in Slovak; a robotnik is a peasant or serf.
Science
fiction writers have devoted many volumes to robots and their
interaction with humans. Of particular note is the work of Isaac Asimov,
who has centered a large portion of his work on robot-related stories.
In his three "laws of robotics," he codified a simple set of behaviors
for robots to remain at the service of their human creators.
Literary
works have adopted specialized terminology when referring to different
types of robots. For instance, the term "robot" has come to mean a
mechanical human, while "android" is used for an artificial human with
organic parts, and "cyborg" or "bionic man" refers to a human form that
contains both organic and mechanical parts. Organic artificial humans
have also been referred to as "constructs."
Robotics
The term robotics
refers to the technology that involves the design, manufacture, and
uses of robots. Someone who works in the field of robotics is called a roboticist.
This person requires a working knowledge of electronics, mechanics, and
software. The word robotics was first used in print by Isaac Asimov in
his science fiction short story “Liar!”.
Although robots vary in
appearance and capabilities, they share the features of a mechanical,
movable structure under some form of control. Generally, a robot's
structure acts like the skeleton of a body and is called a “kinematic
chain.” The chain is formed of links (the robot's "bones"), actuators
(the robot's "muscles"), and joints. In most contemporary robots, each
link connects the one before it to the one after it. These structures
often resemble the human arm. When a robot is needed to manipulate
objects, the last link carries an "end effector," which can be anything
from a mechanical hand to a welding device.
A robot's mechanical
structure needs to be controlled on various levels, so that the device
can recognize patterns, move along certain paths, avoid obstacles, and
perform various tasks. The control of these functions usually involves
three phases: perception, processing, and action (robotic paradigms).
The robot has sensors that pick up information about the environment or
the robot itself, such as the position of its joints or its end
effector. Using strategies from the field of control theory, this
information is processed to calculate the appropriate signals that need
to be sent to the actuators (motors), and these in turn move the
mechanical structure. Complex and adaptable control strategies may be
referred to as artificial intelligence.
To perform any task, the
robot needs the ability to move. When designing a robot, the roboticist
needs to consider its motion in terms of (a) kinematics, or motion apart from the forces that cause the motion, and (b) dynamics,
or motion in conjunction with the forces that affect it. The
information gathered by studying the various possible motions can be
used to improve the algorithms that control the robot's actions.
Types and uses of robots
As
robots grow in number and complexity, they are being more widely used
in industry. Most often, they are used to perform repetitive tasks.
Industrial robots can be manufactured in a wide range of sizes and can
therefore handle much larger tasks than a human can. In addition, robots
are useful in environments that are unpleasant or dangerous for people
to work in, such as in toxic waste cleanup, bomb disposal, mining, and
working in outer space or deep water.
Certain mobile robots,
called automated guided vehicles (AGVs), are used in large facilities
such as warehouses, hospitals, and container ports, for the transport of
goods and for safety and security patrols. Such vehicles can be
programmed to follow wires, markers, or laser guides to navigate around a
given location.
Some robots are available for performing
domestic tasks such as cooking, vacuum cleaning, and lawn mowing. In
addition, robot kits made of plastic or aluminum are becoming
increasingly popular for education in schools and professional training
by companies.
Humanoid robots are being developed with the aim of
providing robotic functions in a form that may increase their appeal to
customers. These types of robots, known as social robots, are made to
interact with and provide companionship to people.
Industrial robots
So
far, the main use of robots has been in the automation of
mass-production industries, where well-defined tasks must be repeated in
exactly the same fashion, with little need for feedback to control the
process. Typical applications of industrial robots include welding,
painting, ironing, assembly, picking and placing, palletizing, product
inspection, and testing. They can accomplish all these tasks with high
endurance, speed, and precision. A prime example is automobile
manufacture, in which large, complex robots are used.
The
International Organization for Standardization (ISO) has officially
defined an industrial robot as an "automatically controlled,
reprogrammable, multipurpose manipulator, programmable in three or more
axes." Most industrial robots would fall in the category of robotic
arms, as implied by the term "manipulator" in this definition.
Industrial
robots exhibit varying degrees of autonomy. Many are programmed to
perform specific actions over and over again, without variation, and
with a high degree of accuracy. Other industrial robots are built to be
much more flexible about the orientation of the object on which they are
operating or even the task that has to be performed, which the robot
may need to identify. For example, these robots may contain machine
vision subsystems acting as their "eyes," linked to powerful computers
or controllers. Artificial intelligence, or what passes for it, is
becoming an increasingly important factor in the modern industrial
robot.
Humanoid robots
A
humanoid robot is a robot that is built to imitate the structure of the
human body and to perform some of the same physical and mental tasks
that humans can do. It is also built to function autonomously, in the
sense of being able to adapt to changes in its environment or itself and
continue to reach its goal. This is the main difference between
humanoids and other types of robots, such as industrial robots, which
perform tasks in highly structured environments. Consequently, humanoid
robots are more complex than other kinds of robots and are more
difficult to develop.
The capacities of a humanoid robot may
include (a) autonomous learning, that is, learning new capabilities and
adapting to new situations without outside assistance; (b)
self-maintenance, such as the ability to recharge its batteries; (c)
interacting safely with humans and the environment; and (d) avoiding
situations that could harm others or itself.
To build and study
humanoids, researchers need to understand the human body structure and
behavior. Consequently, an important benefit of the work to develop
humanoids is that it could lead to a better understanding of human
biological and mental processes, from the seemingly simple act of
walking to the concepts of consciousness and spirituality.
Research
into humanoids is valuable in the medical field, such as in efforts to
construct realistic leg and forearm prosthetic devices for amputees, or
devices that help straighten deformed limbs. In addition, humanoid
robots are being developed to assist the sick and elderly, or to perform
dirty or dangerous jobs. The long-term goal of the creators of humanoid
robots is that someday these devices will be able to understand human
intelligence, reason and act like humans, and work alongside humans.
Humanoid
robots are becoming increasingly popular in the realm of entertainment.
For example, the female robot Ursula sings, dances, and speaks to her
audiences at Universal Studios. Several Disney attractions employ the
use of animatrons—robots that look, move, and speak like human beings—in
some of their theme park shows. These animatrons look so realistic that
it can be hard to decipher from a distance whether or not they are
actually human. Despite their realistic appearance, they have no
cognition or physical autonomy.
Current developments
Recently,
background technologies of behavior, navigation, and path planning have
been solved for basic wheeled robots. Consequently, roboticists are
moving on to develop walking robots, including SIGMO, QRIO, Asimo, and
Hubo. The field of robot research inspired by the principles of
biological systems is known as “biomorphic robotics.”
It is
extremely difficult to develop a robot that can move with a natural
human or animal gait. One reason is that human and animal body movements
involve a very large number of muscles, and replicating them
mechanically is difficult, expensive, and requires a large amount of
computational power. A major challenge in creating a bipedal robot is in
getting it to keep its balance. Initial work has therefore focused on
building multi-legged robots such as hexapods, which are statically
stable and easier to work with.
Researchers are making progress
in the area of feedback and tactile sensors, which give a robot the
ability to sense its actions and adjust its behavior accordingly. This
ability allows the robot to perform complex physical tasks that require
some active control in response to the situation.
Recently,
regulatory approval was granted for the use of robots in minimally
invasive medical procedures. Robots are also being considered for use in
performing highly delicate, accurate surgery. In the future, a surgeon
may use a remotely controlled robot to perform a procedure on a patient
when the two are separated by a considerable distance.
Experimental
winged robots and other devices exploiting biomimicry are also in early
development. By using so-called "nanomotors" and "smart wires,"
researchers are attempting to drastically simplify motive power. In
addition, they are using extremely small gyroscopes to improve the
robot's stability during flight. A significant driver of this work is
military research into spy technologies.
Future prospects
Various
ideas have been advanced about the types of robots that will emerge in
the future and how they will affect people materially and emotionally.
Some scientists believe that in the first half of the twenty-first
century, robots will be built to approximate humanlike intelligence.
Whether or not that becomes a reality, it seems likely that robots will
be increasingly used in homes and offices, replacing "dumb" appliances
with "smart" robotic equivalents. Domestic robots capable of performing
many household tasks may be greatly improved.
In his book The Human Use of Human Beings
first published in 1950, cybernetics pioneer Norbert Wiener discussed
the issue of robots replacing humans in various fields of work. He
speculated that robots taking over human jobs may initially lead to
growing unemployment and social turmoil, but in the medium-term, it may
increase the wealth of people in most nations.
In 1970, Japanese
roboticist Masahiro Mori postulated a principle called the "Uncanny
Valley." He theorized that as a robot is made more humanlike in
appearance and motion, people will respond with increasing empathy and
positive emotion, until a point is reached at which the response
suddenly becomes strongly repulsive. In his view, if the robot's
appearance and motion are made indistinguishable from a human's, the
emotional response will once again become positive, approaching
human-human empathy levels. The repulsive response to an "almost human"
robot was described as the "Uncanny Valley." Some roboticists have
heavily criticized this theory.
Occasionally, the same
technologies may be useful in both robotics and medicine. For instance,
artificial parts such as pacemakers are already being used to repair the
human body. In this sense, there is some degree of convergence between
humans and robots.
Concerns about robots
Frankenstein
(1818), sometimes called the first science fiction novel, has become
synonymous with the theme of a robot or monster advancing beyond its
creator. Since then, a wide range of books and films have expressed
fears and concerns about robots, particularly humanoid robots. The
principal theme is that they may acquire intelligence and abilities
superior to those of humans, then break away from human command, develop
the motivation to take over the world, and destroy the human race.
These
ideas have raised several additional concerns. For instance, who should
be held responsible when an intelligent machine commits a crime, or
does something it should not do? What would be the difference between
the rights of humans and those of humanoids? If a robot were to produce
its own inventions, who should the patent rights be awarded to?
These
concerns, however, are based on fictional concepts that circumvent the
reality that robots are machines with their own mechanical limitations
and devoid of the human spirit. Although robots may be built with
abilities that simulate human intelligence and decision-making traits to
some degree, these abilities depend on artificially programmed feedback
loops, not on creative thinking, deep emotions, and responsible
volition—qualities that drive human aspirations and freedom of
expression. From this perspective, real-world robots cannot be expected
to have their own motivations to commit crimes or to exert independent
creativity and responsibility to produce beneficial inventions. One may
infer that the abilities, activities, and value of robots will continue
to remain apart from those of humans.
A more realistic concern is
that when robots are used to perform tasks usually done by human
beings, they may displace people from their jobs, such as in factories.
This issue requires solutions that are sensitive to people's needs.
One
possible danger may take the form of harmful programming or unsafe use
of robots. Even without such programming, a robot that moves freely in a
human environment is potentially dangerous because of its large moving
mass, powerful actuators, and unpredictably complex behavior. A robot
that accidentally falls on someone or even steps on a person's foot
could injure the victim far more than another human of the same size.
Most industrial robots are therefore confined within a protective fence
that separates them from human workers. Designing and programming robots
to be intrinsically safe, and to exhibit safe behavior in a human
environment, is one of the great challenges in robotics.
Robot competitions
Competitions
for robots are gaining popularity and cater to a wide variety of robot
builders, ranging from students in schools to professionals in research
institutions. The robots are made to compete in a wide range of skills,
including combat, game playing, maze solving, performing tasks, and
navigational exercises.
Dean Kamen, Founder of FIRST (For Inspiration and Recognition of Science and Technology),
has created the world's leading robotics competitions for students in
elementary, middle, and high schools. This highly competitive,
multinational program teams professionals and young people to solve an
engineering design problem, including the creation of autonomous and
driver-controlled robots. Four competitions have been set up for
students in four different age groups.
RoboCup is an
international competition dedicated to developing a team of fully
autonomous, humanoid robots that can win against the human world soccer
championship team by the year 2050. The underlying aim is to promote
research and education in the field of artificial intelligence. RoboCup
Junior is a similar competition set up for school-aged students. All
robots are designed and developed solely by the students and act
autonomously, without any form of remote control or human intervention.
The
DARPA Grand Challenge is a competition for robotic vehicles to complete
an under-200 mile, off-road course in the Mojave Desert. The unclaimed
2004 prize was $1,000,000. The farthest any participant got was only 7.4
miles. However, the 2005 prize of $2,000,000 was claimed by Stanford
University. In this race, four vehicles successfully completed the race.
This is a testament to how fast robotic vision and navigation are
improving.
The Intelligent Ground Vehicle Competition () is an
annual event for university students who are expected to construct
autonomous ground vehicles that traverse outdoor obstacle courses
without any human interaction. This international competition is
sponsored by the Association for Unmanned Vehicle Systems International.
The
American Association for Artificial Intelligence sponsors two Grand
Challenges focusing on human-robot interactions. In addition, NASA holds
the Centennial Challenges for non-government funded technological
achievements, including robotics. In Micromouse competitions, small
robots try to solve a maze in the fastest time.