PC-DMIS supports the following software error compensation methods for this Sheffield interface:
Direct Error Comp from MP Unit
This is the simplest form of compensation and requires that the machine is an "MEA" type (usually signified by red trim on the machine and MP unit) and that its calibration date has not expired. PC-DMIS reads hit values directly from the MP unit. The PC-DMIS Settings Editor registry entry MPHits must be set to 1 for this option to work.
PC-DMIS supports the capability for non-linear error compensation of the rotary table for the above options. That is, it adjusts for scale errors. For information on other compensation methodologies and settings, see "Volumetric Compensation".
To make use of this capability, you need to have your rotary table CMM "shot" with a laser. Alternatively, if the MP unit is within its calibration dates, you can use the MP W axis values as the true "beamed" values. All values must be collected from the home position of the rotary table.
The following commands should be entered into a file called "COMP.ERR". This file should be in the root of the PC-DMIS install directory, and the commands should be in all uppercase:
STARTW
This command specifies the beginning of the W axis data. This should be the data connected to the W counter port.
All data within a data block should be specified in the following format:
scale reading=laser reading
For example, if the scales report 4.5666 degrees and the laser reports 4.5678 degrees, then the entry in the data section would be:
4.5666 = 4.5678
END
This command specifies the end of an axis data block for W.
Example:
STARTW
0.0=0.0
10.0=10.002
30.001=30.023
40.002=40.01
END