Calibrating Probe Tips

Calibrating your probe tips tells PC-DMIS the location and diameter of your probe tips. You cannot execute your measurement routine and measure your part until you calibrate the probe tips. The terms "calibrate" and "qualify" are used interchangeably.

To begin the calibration process:

  1. Make sure the Active tip list in the Probe Utilities dialog box (Insert | Hardware Definition | Probe) has the desired tip angles.

  2. Select the probe tip or tips that you want to calibrate from the list.

  3. Click Measure to display the Measure Probe dialog box.

If you have a probe changer and the currently active probe file is not the probe configuration in the probe head, PC-DMIS automatically drops off the currently loaded probe configuration and picks up the needed one.

Number of Hits Prehit / Retract Move Speed Touch Speed Type of Operation Area Calibration Mode area Wrist Calibration area Shank Qualification Number of Shank Hits Shank Offset Parameter Sets area Tool Mounted on Rotary Table System Mode

Measure Probe dialog box

The Measure Probe dialog box displays settings that apply to measurement for the purpose of probe qualification. Once you make the desired selections, click Measure to begin.

Requirements Prior to Calibration

To begin the calibrating process, you must define a qualification tool. The type of measurement(s) to be made on the tool depends on the type of tool (typically a SPHERE) and the type of tip (BALL, DISK, TAPER, SHANK, OPTICAL).

Once Calibration Starts

PC-DMIS displays one of two styles of messages that ask if the qualifying tool has been moved. The type depends on your machine's ability to use DCC hits to locate the qualification tool:

YES/NO Message Box

This message box appears for machines that do not support the ability to locate the qualification tool using DCC hits (such as manual-only machines):

PC-DMIS

Has the qualification tool been moved or has the machine zero point changed? WARNING: Tip is about to rotate to TIP1!

Yes No

Qualification Tool Moved Dialog Box

The Qualification Tool Moved dialog box appears if your measuring machine and probe configuration support the ability to locate the qualification tool using DCC hits:

Qualification Tool Moved dialog box

For a tactile probe on a Bridge-type CMM, PC-DMIS will continue with the automatic calibration routine.

For a tactile probe on a Bridge-type CMM, you have to manually hit the sphere to locate the tool position.

About the Leg Collision Check for a Bridge CMM During Calibration

At this point, for a tactile probe on a Bridge-type CMM, PC-DMIS displays the Collision Check dialog box. It asks if you want to run the Leg Collision check:

Collision Check dialog box - collision check message

Collision Check dialog box - name of tip

The Leg Collision check takes a few seconds to run. The time depends on the number of tips selected. You can use the Stop or Cancel button to stop or cancel the check. If needed, PC-DMIS adds safety movements (retracting the tip along X or Y ) to avoid possible collisions with the CMM legs, and safety movements in Z to avoid possible collisions with the plate, roof, or gauge sphere.

After PC-DMIS runs the Leg Collision check, it executes the calibration routine which was improved with the safety movements, if needed.

In a few situations, the Leg Collision check may find some probe tip rotations that cause collisions that it cannot automatically resolve. In these cases, the calibration cannot safely execute, and PC-DMIS interrupts the calibration. It shows a "Can't calibrate" message and lists those problem tip names.

The Leg Collision check is available when you run the calibration routine directly with the PC-DMIS interface or AUTOCALIBRATE command, and only with vertical calibration tools. It is not available for star probes. It does not work with Automation functionality.

Once Measurement Finishes

Once the measurement finishes, PC-DMIS calculates the qualification results as appropriate for the type of probe, tool used, and operation requested. The difference between the two Yes options in the Qualification Tool Moved dialog box only affects whether or not a manual hit is needed during measurement. For purposes of the post-measurement calculations, both Yes options are equivalent.

Following calibration, a brief summary for each tip is visible in the Active Tip List in the Probe Utilities dialog box. To see detailed results of the calibration, click Results in that dialog box.

Recalibrating

In general, PC-DMIS cannot tell if a probe tip needs to be recalibrated. Be sure to perform a recalibration if anything changes with your probe.

More:

Number of Hits

Prehit / Retract

Move Speed

Touch Speed

System Mode

Type of Operation area

Calibration Mode area

Wrist Calibration area

Shank Qual

Number Shank Hits

Shank Offset

Parameter Sets area

Tool Mounted on Rotary Table

Reset Tips to Theo at Start of Calibration

Tips to Use if None Explicitly Selected

Measure