Siemens SINUMERIK 840Di Function Manual page 821

2.4.8 Predefined frame functions
2.4.8.1 Inverse frame
To round off the frame arithmetic, the part program provides a function which calculates the
inverse frame from another frame. The chaining between a frame and its inverse frame
always produces a zero frame.
FRAME INVFRAME( FRAME )
Frame inversion is an aid for coordinate transformations. Measuring frames are usually
calculated in the WCS. If you should wish to transform this calculated frame into another
coordinate system, i.e., the calculated frame should be entered into any desired frame within
the frame chain, the calculations below should be used.
The new complete frame is a chain of the old complete frame and the calculated frame.
$P_ACTFRAME = $P_ACTFRAME : $AC_MEAS_FRAME
The new frame in the frame chain is therefore:
Target frame is $P_SETFRAME:
$P_SETFRAME = $P_ACTFRAME : $AC_MEAS_FRAME : INVFRAME($P_ACTFRAME) :
$P_SETFRAME
Target frame is nth channel basic frame $P_CHBFRAME[n]:
n = 0: TMP = $P_PARTFRAME : $P_SETFRAME : $P_EXTFRAME : $P_NCBFRAME[0..k]
n <> 0: TMP = $P_PARTFRAME : $P_SETFRAME : $P_EXTFRAME : $P_NCBFRAME[0..k] :
$P_CHBFRAME[0..n-1]
k = $MN_MM_NUM_GLOBAL_BASE_FRAMES
$P_CHBFRAME[n] = INVFRAME(TMP) : $P_ACTFRAME : $AC_MEAS_FRAME :
INVFRAME($P_ACTFRAME) : TMP : $P_CHBFRAME[n]
Target frame is $P_IFRAME:
TMP = $P_PARTFRAME : $P_SETFRAME : $P_EXTFRAME : $P_BFRAME
$P_IFRAME = INVFRAME(TMP) : $P_ACTFRAME : $AC_MEAS_FRAME :
INVFRAME($P_ACTFRAME) : TMP : $P_IFRAME
Application example:
A frame calculated, for example, via a measuring function, must be entered in the current
SETFRAME such that the new complete frame is a chain of the old complete frame and the
measurement frame. The SETFRAME is calculated accordingly by means of frame inversions.
DEF INT RETVAL
DEF FRAME TMP
$TC_DP1[1,1]=120 ; Type
$TC_DP2[1,1]=20.;0
Axis Types, Coordinate Systems, Frames (K2)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Detailed Description
2.4 Frames
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