Interpolatory Compensation; General Properties - Siemens SINUMERIK 840D sl Function Manual

5.4

Interpolatory compensation

5.4.1

General properties

Function
With "interpolatory compensation," deviations between the desired and the actual position of
an axis can be compensated by leadscrew, measuring system, sag and angularity errors. This
is done by determining the deviation by measurement and storing the corresponding
compensation values in one or more compensation tables in the NC. During operation, the
relevant compensation value is then determined from the compensation table or tables for a
compensation axis based on its current set position. Linear interpolation is performed between
the interpolation points of the compensation tables.
Within "interpolatory compensation", a distinction is made between the two following
compensation methods:
● Compensation of leadscrew errors and measuring system errors
● Compensation of sag and angularity errors
Terms
● Compensation value
Additional setpoint that is applied to the compensation axis so that the difference between
the desired and actual axis position is zero.
● Basic axis
Axis, via whose set and actual position, the compensation value is determined from the
compensation value.
● Compensation axis
Axis, to whose set or actual position the compensation value is applied.
● Interpolation point
Value pair in a compensation table, consisting of a set and actual position of the basic axis
(interpolation point) and the associated compensation value (interpolation value).
● Compensation table
Defined number of interpolation points for a defined traversing range of the basic axis.
● Compensation relation
Unit comprising the basic axis, compensation axis, and compensation table.
Entering compensation tables
The size of the compensation table, i.e. the number of interpolation points, must first be defined
in a machine data. After the next POWER ON, the compensation tables are generated by the
NC and preassigned a value of "0".
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
K3: Compensations
5.4 Interpolatory compensation
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