General configuration (obligatory)
Volumetric Compensation(s) takes place
- in the start-up list "hochlauf.lis" [STUP//Chapter Volumetric Compensation] and
- in the compensation-specific lists [VOLC].
Up to five compensations can be configured for each controller. Configuration of more than only one compensation makes sense on multi-channel machines, for example. Moreover, the measuring strategy can influence whether you have to work with one or more compensations; see Section “Influence of measuring strategy on configuration”.
Axis assignment
Volumetric Compensation requires the presence of
- 3 translatory axes and
- up to 3 rotary axes.
The ISO standard stipulates the letters X, Y, Z, A, B and C as axis names.
Which physical axis assumes the role of the X axis, the Y axis, etc. is assigned by the logical axis number.
Notice | |
This axis assignment must match the axis identifier when the machine is measured. Otherwise, the compensation values are assigned to the wrong aces and this results in an inexact TCP position during machining. |
Programming Example
Axis assignment in compensation list
Number of records
For memory allocation, a bound must be specified for the number of records to be read. An error is issued if this number is exceeded when the parameter files are read in.
Programming Example
Example – number of records in "hochlauf.lis"
Parameter files
Up to 10 parameter files can be used for each compensation. A file name and the file format used must be specified for each parameter file.
The following names are available for the file format.
Name | File format |
ISG_CSV | ISG CSV file format, see section “ISG CSV format” |
ETALON_EXCHANGE | Etalon Exchange Format, see section “Etalon Exchange Format” |
Programming Example
2 parameter files in compensation list
Kinematic model
Further information is needed to completely describe the machine kinematic model. In particular, the sequence of axes in the kinematic chain must be specified.
Under certain circumstances, the number of axes located on the workpiece side must be specified. Whether this value must be specified depends on the measuring strategy, see section “Influence of the measurement strategy on configuration”.
Programming Example
Kinematic model in compensation list
Specifying the kinematic chain starts with the workpiece and then runs along the axes up to the tool. The sequence in which the axes occur specifies the kinematic chain. In this example, we have a CBYXZkinematic. |
Limit value
A limit for the compensation value must be specified in the axis parameters for each of the axes to be compensated (previously X, Y, Z).
The lr_param.vol_comp.s_limit (P-AXIS-00525) parameter defines the maximum allowed compensation value for this axis. If this value is exceeded, an error is issued and the axis is stopped in a controlled manner.
Notice | |
If this limit is not defined, an error is issued when compensation is activated. |
Programming Example
Limit in "achsmd1.lis"
Notice | |
The s_limit limit must also be defined for gantry axes whose master axes are involved in Volumetric Compensation. Otherwise, an error is output when a compensation value is applied. |