Page 283 - Concise Encyclopedia of Robotics

Robot Classification
ROBOT ARM
There are numerous ways in which a robot arm can be designed. Different
configurations are used for different purposes. Some robots, especially
industrial robots, are nothing more than sophisticated robot arms. Robot
arms are sometimes called manipulators, although technically this term
applies to the arm and its end effector, if any.
A robot arm can be categorized according to its geometry. Two-
dimensional (2-D) designs have work envelopes limited to a section of a
flat plane. Most robot arms can work within a region of three-dimensional
(3-D) space.
Some robot arms resemble human arms. The joints in these machines
are given names like “shoulder,” “elbow,” and “wrist.” Some robot arms,
however, are so very different from human arms that these names do not
make sense. An arm that employs revolute geometry is similar to a human
arm,but an arm that uses Cartesian coordinate geometry is far different.For
further information, see ARTICULATED GEOMETRY, CARTESIAN COORDINATE GEOMETRY, CYLIN-
DRICAL COORDINATE GEOMETRY, POLAR COORDINATE GEOMETRY, REVOLUTE GEOMETRY, SPHERICAL
COORDINATE GEOMETRY, and WORK ENVELOPE.
ROBOT CLASSIFICATION
In the late twentieth century, the Japan Industrial Robot Association
(JIRA) classified robots from simple manipulators to advanced systems
incorporating artificial intelligence (AI). From low-end to high-end, the
JIRA robot classification scheme proceeds as follows:
1. Manually operated manipulators: Machines that must be directly
operated by a human.
2. Sequential manipulators: Devices that perform a series of tasks in
the same sequence every time they are actuated. A good example is
a telephone answering machine.
3. Programmable manipulators: These include the simpler types of
industrial robots familiar to most people.
4. Numerically controlled robots: Examples are servo robots.
5. Sensate robots: Robots incorporating sensors of any type, such as
back pressure, proximity, pressure, tactile, or wrist force.
6. Adaptive robots: Robots that adjust the way they work to compensate
for changes in their environment.
7. Smart robots: Robots with high-end controllers that can be con-
sidered to possess AI.
8. Intelligent mechatronic systems: Computers that control a fleet of
robots or robotic devices.

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