Siemens SINUMERIK 840D sl Function Manual page 710

K2: Axis Types, Coordinate Systems, Frames
10.5 Frames
Meaning
<Frame>:
<Index>:
<GAx>:
RT:
<Angle>
Reading back the rotation components
In general, the same values are obtained when reading back the rotation components of a
frame as those that were programmed:
<Frame>=CROT(X,45,Y,30,Z,-20)
1) The values of the saved rotation components are obtained when reading back
Values outside the value range
Programmed values outside a value range are mapped on the range limits:
<Frame>=CROT(X,190,Y,0,Z,-200)
1) The values of the saved rotation components are obtained when reading back
Note
It is recommended that when writing the rotation components of the frame, the specified value
ranges are observed so that the same values are obtained when reading back the rotation
components.
Gimbal lock
Gimbal lock designates a geometric problem in which the rotation components can no longer
be unambiguously calculated back from the position vector. Gimbal lock occurs in RPY angles
with an angular position of the rotation component y = 90°. In this case, the rotation components
are converted by the controller after being written so that the following applies:
● Rotation component z = rotation component z - rotation component x
● Rotation component x = 0°
● Rotation component y = 90°
710
Arbitrary active or data management frame
Array index of the frame, e.g. $P_UIFR[0 ... n]
Name of the geometry axis around which rotation is to be performed
with the specified angle.
Keyword for rotation "RoTation"
Angle specification in degrees.
Programmed
Programmed
Saved rotation components
x, RT y, RT
45 30
Saved rotation components
x, RT y, RT
0
-170
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
1)
z, RT
-20
1)
z, RT
160
Basic Functions