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The file $MACHINE.DAT (continued)
13 of 91
Maschinendaten 12.0400 en
2.1.8
$ROBROOT
Offset and orientation
Data type
----
min
Value
----
Unit
mm, degrees
Value
max ----
Assignment
FRAME {X, Y, Z, A, B, C}
Offset and orientation of the robot relative to the world coordinate system.
Ceiling--mounted robots:
Angle C is 180 degrees
Wall--mounted robots:
Angle B is 90 degrees
The frame chain or vector chain of the robot arm (axes 1 to 6) without external axes is
illustrated in Fig. 2:
X
Y
A 1
A 2
A 4
A 3
A 5
A 6
$ROBROOT
Z
$WORLD
X
Y
Z
$BASE
Workpiece
X
Y
Z
$TOOL
$POS_ACT
X
Y
Z
Robot
Fig. 2
Frame chain without external axes
The BASE coordinate system is used as the reference system to define the position of the
workpiece. The programming of the robot is done in the BASE coordinate system, which has
the WORLD coordinate system as its reference coordinate system.
When interpolating the motion path, the robot controller calculates, under normal
circumstances (stationary workpiece, tool mounted on the robot flange), the current position
($POS_ACT) in relation to the $BASE coordinate system.
