Siemens SINUMERIK 840C - Manual (Page 979)

12 Functional Descriptions 09.95
12.19.5 Interpolation and compensation with tables
12.19.5.6 IKA calculation sequence
IKA calculation sequence
Link type K11/K12
Input switching module: LINK ON/OVER/OFF, pos. rel.
Input evaluation module: T18/T19,
T15, T16
Interpolation switching module of IKA SW 4
Output evaluation via
numerator/denominator
Limiting module: Following axis/
spindle-specific MD, interface
Up to 5 leading axis/spindle
paths and 1 overlay path
Z
*LRFFA
N
*LRFLA
MD, NS
KGI SW 4
T4 T30
T31/T32 T34
K46
MD, NS
Input selection module (input quantity A): T2/T20)
Input switching module: T11, T17/T41/T42
Input evaluation module: T18/T19, T15, T16
Interpolation module: T0, T1, T12/T13, T40/T43
Output evaluation module: T4/T30, T31/T32/T34
Input selection module (input quantity B): T25/T26
Output evaluation module: T3/T33
Global IKA module: T1, T5/T6, T7-T10
Compensation limiting module: Axis-spec. MD, interface
Modulo calculation T16
IKA SW 4
*T18 T15 T16 T19
The block diagram shows the calculation sequence of the quantities involved in an IKA
configuration.
In the input selection module (1), the preset quantity of input A with respect to input type and
input number is activated.
In the input switching module (2), the position-independent or position-dependent activation or
deactivation of an IKA configuration is performed.
If the IKA configuration is activated, input quantity A is further processed in the global IKA
module (8). First of all, input quantity A is normalized with the weighting factor of input A
(numerator/denominator) in the input weighting module (3). After normalization, the offset and
the modulo calculation are applied. The input value for any offset and the module value must
therefore refer to the normalized input quantity A.
The output quantity is determined in the interpolation module (4). The output quantity is
calculated as a function of the set control curves and various control bits and forwarded to the
output weighting module (5). Multiplication with the input quantity B is performed here. In input
selection module (6), input quantity B is selected in accordance with the input type and
number set. Moreover, further calculation of the output value is possible via the weighting
factors of the output (numerator/denominator) in the output weighting module. The
denominator of the output weighting can also be seen as the weighting of input quantity B.
After output weighting, the output quantity is limited with respect to position and velocity. The
output selection module assigns the output values to the specified output quantity.
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SINUMERIK 840C (IA)