HEIDENHAIN TNC 410 ISO Programming - Manual (Page 182)

156 7 Programming: Miscellaneous Functions
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Contour filter: M124 (not TNC 426, TNC 430)
Standard behavior
The TNC includes all available points in its calculation of a contour
transition between contour elements.
Behavior with M124
The TNC filters contour elements with small point spacing and inserts
a transitional contour.
Shape of contour transition
n Tangential circle: MP7415.0 = 0
An acceleration jump results from the change in the curvature at the
connection points.
n Third-degree polynomial (cubic spline): MP7415.0 = 1
There is no velocity jump at the connection points.
n Fifth-degree polynomial: MP7415.0 = 2
There is no acceleration jump at the connection points.
n Seventh-degree polynomial: MP7415.0 = 3 (standard setting)
There is no jump in the rate of acceleration change
Rounding of contour transitions
n Do not round the contour transition: MP7415.1 = 0
Execute the contour transition as defined in MP7415.0 (standard
contour transition: 7th-degree polynomial)
n Round the contour transition: MP7415.1 = 1
Execute the contour transition so that the straight line segments
remaining between the contour transitions are also rounded.
Minimum length E of a contour element
With parameter E you define the length up to which the TNC should
filter contour elements out. If you have defined a permissible contour
deviation in M112, the TNC will respect it. If you do not enter a
maximum contour deviation, the TNC calculates the most exact
contour transition possible without reducing the programmed feed
rate.
You can adjust the effect of M124 by redefining machine
parameters.