Siemens SINUMERIK 808D ADVANCED - Page 247

Programming and Operating Manual (Milling)
6FC5398-4DP10-0BA1, 01/2014
247
For an incremental input,
the absolute distance
to the pole is calculated using the absolute distance from the end point of the
preceding element to the pole plus the length increment that was entered.
The increment can be positive or negative.
The absolute angle
is calculated accordingly using the absolute polar angle of the preceding element plus the angular
increment. It is not necessary here for the preceding element to have been entered as polar.
In contour programming, the contour calculator converts the Cartesian coordinates of the preceding end point using the
definitive pole into polar coordinates. This also applies if the preceding element has been given in polar coordinates, since
this could relate to another pole if a pole has been inserted in the meantime.
Pole change example
Figure A-1 pole change(milling)
Pole:
Xpole = 0.0, Ypole = 0.0, (Pole 0)
End point:
L1abs = 10.0 ϕabs = 30.0° Calculated Cart. Coordinates
Xabs = 8.6603 Yabs = 5.0
New pole:
Xpole1 = 5.0 Ypole1 = 5.0 (Pole 1)
Calculated polar coord. Predecessor
L1abs = 3.6603 ϕabs = 0.0°
Next point:
L1inc = -2.0 ϕinc = 45.0°
Absolute polar coordinates for current element