Siemens SINUMERIK 828D Programming Manual page 372

Coordinate transformations (frames)
12.4 Programmable rotation (ROT, AROT, RPL)
RPY notation (the default setting) results in the following sequence:
1. Rotation around the 3rd geometry axis (Z)
2. Rotation around the 2nd geometry axis (Y)
3. Rotation around the 1st geometry axis (X)
This order applies if the geometry axes are programmed in a single block. It also applies
irrespective of the input sequence. If only two axes are to be rotated, the parameter for the
3rd axis (value zero) can be omitted.
Value range with RPY angle
The angles are defined uniquely only within the following value ranges:
Rotation around 1st geometry axis: -180° ≤ X ≤ +180°
Rotation around 2nd geometry axis: -90° ≤ Y ≤ +90°
Rotation around 3rd geometry axis: -180° ≤ Z ≤ +180°
All possible rotations can be represented with this value range. Values outside the range are
normalized by the control into the above range during writing and reading. This value range
applies to all frame variables.
Examples of reading back in RPY
$P_UIFR[1] = CROT(X, 10, Y, 90, Z, 40)
returns on reading back:
$P_UIFR[1] = CROT(X, 0, Y, 90, Z, 30)
$P_UIFR[1] = CROT(X, 190, Y, 0, Z, -200)
returns on reading back
$P_UIFR[1] = CROT(X, -170, Y, 0, Z, 160)
When frame rotation components are read and written, the value range limits must be
observed to ensure that the same results are obtained for read or write, or repeat write
operations
372
Z
0
2
.
Y
1
X
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
Fundamentals