CRS A255 - Glossary

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Glossary
Arm
A sequentially connected set of links and joints having one end, the base, attached
to a platform, the other end outfitted with a tool which performs work, and the
joints powered and capable of moving the links and the tool to various locations
and orientations.
Awareness Signal
An audio or visual device, such as a buzzer or a light, activated by a sensing
device, which makes aware the nearness of a person to the robot arm work cell or
workspace.
Axis (X, Y, or Z)
A reference line of a coordinate system. In a Cartesian coordinate system, the three
axes (X, Y, Z) meet at right angles, with X and Y defining a horizontal plane and Z
defining the vertical dimension. Any point in the arm’s workspace, i.e. any location
of the gripper or tool, can be identified by this system.
Axis of Motion
A line which passes through a joint about which a link or similar section rotates.
Controller
The computerized device that controls the arm. It receives input, processes data,
sends control signals to the arm, and receives feedback from the arm. During the
running of an application, the controller executes a robot software program.
Degree of Freedom (DOF)
The types of independent motions in which the arm can move its end effector
(gripper, tool), as defined by the axes of motion. For example, the A255 has five
degrees of freedom and can move to coordinates specified by X, Y, Z, Pitch, and
Roll.
Emergency Stop (E-stop)
A method that overrides robot controls, removes arm power, and stops movement
of the robot arm.
Encoder
A device attached to each motor shaft which converts the movement of a joint to a
signal for processing by the controller.
End Effector
A device attached to the tool flange that is used to perform the robot’s task, such
as a gripper, dispenser, buffing wheel, or spray head.
Gripper
An end effector designed to grasp or hold.
Harmonic Drive
A precision mechanical transmission. This device joins a motor and a joint
providing smooth motion, high torque, and low backlash. A harmonic drive
contains three components: circular spline, flexspline, and wave generator. The
circular spline is a rigid ring with internal teeth which engage the external teeth of
the flexspline. The flexspline is a non-rigid, thin cylindrical cup with external teeth