Scanning

Requirements

In order to use PC-DMIS to scan your parts with an analog probe (SP600 or SP25), there are several requirements that need to be met.

Functionality

The chart below summarizes the available PC-DMIS scanning features and the status of their support on Sheffield CMM’s with the SMP400.

PC-DMIS SCAN TYPES SUPPORTED? NOTES
LINEAROPEN YES The SMP400 only supports Line Technique (constant increment) and Spherical Boundary.
LINEARCLOSED YES
PATCH YES
CIRCLE YES Open-loop and closed-loop.
CYLINDER YES
AXIS YES Closed-loop
CENTER YES
LINE YES
ROTARY NO This is part of a future development effort.
SECTION NO This is in the testing phase and is not released at this time.
UV NO This is in the testing phase and is not released at this time. This is for Touch mode only.
FREEFORM NO To implement this scan type requires defined scans which are not supported on the SMP400.
PERIMETER NO To implement this scan type requires defined scans which are not supported on the SMP400. Closed-loop.

 

Unsupported scan controls/methods

Scanning Limitations

OPEN/CLOSED LOOP Scanning

If you wish to control the type of scan being performed for a measurement routine, you must quit PC-DMIS and launch the Settings Editor.

OPEN LOOP UseClosedLoop FALSE

CLOSED LOOP UseClosedLoop TRUE

There are no controls to change to Open or Closed with PC-DMIS commands, or by the loss of surface with an Open loop. The global value defined in the PC-DMIS Settings Editor application is a global default.

Scan Speeds

Recommended Settings

Settings Editor

Settings Name Recommended Value Comment
MovePositionTol 1 -
MPHits 1 -
MPVectors 1 -
PointDensity 4 -
ScanSpeed 150 ScanSpeed is the systems? MAXIMUM allowable scanning speed.
SendProbeOffsets TRUE -
SMP400Baud 57600 or 115200 (recommended) You can configure the baud rate settings on board the SMP400 by the jumper pin location. Contact Hardware Technical Support to change from 57600 to 115200.
UpdateComm FALSE -
UseVectorTouch FALSE -
UseNewCancel TRUE -
UsePartAlignment FALSE -

Parameter Settings - Opt. Probe tab

Settings Name Recommended Value Comment
# of Return Data 0 Set this to 0 (zero) to disable the controller-based scan filtering. PC-DMIS requires unfiltered scan data from the controller. Filtered data results in an undersized measurement.
Positioning Accuracy 10 -
Probing Accuracy 1 -
PointDensity See comment. This represents the number of readings to record per mm. Since this is an application-specific setting, you may need to contact Hexagon Technical Support to set this value to a particular number.
Offset Force CMM Model Dependent Set this value to 0.150 for an Endeavor CMM, or 0.250 for a Discovery or Apollo CMM.