Basic Characteristics RAPID

Coordinate Systems Motion and I/O Principles
The object coordinate system is defined based on the user coordinate system (see Figure 4).
User coordinate system
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Figure 4 Two object coordinate systems describe the position of two different work objects
located in the same fixture.
The programmed positions are always defined relative to an object coordinate system.
If a fixture is moved/turned, this can be compensated for by moving/turning the user
coordinate system. Neither the programmed positions nor the defined object coordinate
systems need to be changed. If the work object is moved/turned, this can be
compensated for by moving/turning the object coordinate system.
If the user coordinate system is movable, that is, coordinated external axes are used,
then the object coordinate system moves with the user coordinate system. This makes
it possible to move the robot in relation to the object even when the workbench is being
manipulated.
1.2.5 Displacement coordinate system
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y
World coordinate system
x
x
y
z
Object coordinate system 2
Sometimes, the same path is to be performed at several places on the same object. To
avoid having to re-program all positions each time, a coordinate system, known as the
displacement coordinate system, is defined. This coordinate system can also be used in
conjunction with searches, to compensate for differences in the positions of the
individual parts.
The displacement coordinate system is defined based on the object coordinate system
(see Figure 5).
6-6 RAPID Reference Manual
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Object coordinate system 1
y
x
y
x