Command: Force - Universal Robots UR3/CB3 User Manual

A "Box" pattern uses three vectors to define the side of the box. These three vectors are
given as four points, where the first vector goes from point one to point two, the second
vector goes from point two to point three, and the third vector goes from point three to
point four. Each vector is divided by the interval count numbers. A specific position
in the pattern is calculated by simply adding the interval vectors proportionally.
The "Line" and "Square" patterns work similarly.
A counter variable is used while traversing the positions of the pattern. The name of
the variable can be seen on the Pattern command screen. The variable cycles through
the numbers from 0 to X Y Z
can be manipulated using assignments, and can be used in expressions.

14.24 Command: Force

Force mode allows for compliance and forces in selectable axis in the robot's workspace.
All robot arm movements under a Force command will be in Force mode. When the
robot arm is moving in force mode, it is possible to select one or more axes in which
the robot arm is compliant. Along/around compliant axes the robot arm will comply
with the environment, which means it will automatically adjust its position in order to
achieve the desired force. It is also possible to make the robot arm itself apply a force
to its environment, e.g. a workpiece.
Force mode is suited for applications where the actual tcp position along a predefined
axis is not important, but instead a desired force along that axis is required. For exam-
ple if the robot TCP should roll against a curved surface, or when pushing or pulling
CB3
1, the number of points in the pattern. This variable
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14.24 Command: Force
Version 3.3.3