Recommended FARO Scanner Settings

FARO Scanner Settings for VTube-LASER

This is a guide for FARO scanner setup with VTube-LASER.

PRINCIPLE 1: LLP Camera Exposure Modes Depend on the FARO Scanner Version

The diagram shows the acceptable workable exposure settings with the different versions of FARO scanners when measuring tube shape.

In some cases, the older version scanners can use AUTOMATIC modes, but the cylinder calculation is not as reliable in these modes.

For version 2 and version 3 scanners, passing the 4-level cylinder fit-test in VTube-LASER 2.8 or newer when scanning tubes is almost impossible. In this case, the only solution is to use FIXED mode in the FARO Laser Line Probe Control window.

PRINCIPLE 2: FIXED Exposure Mode is better than AUTOMATIC Exposure Mode for Reliability

An important principle we've discovered is that FIXED exposure mode is more reliable than AUTOMATIC exposure mode in returning consistently accurate surface points when measuring a cylinder.

The difference in reliability between FIXED and AUTOMATIC exposure modes depends on the scanner version. The difference is usually minimal with version 6 (the HD blue line scanner). With older versions, the difference can be more of an issue. Whether or not the difference matters is easily detected and reported by VTube-LASER's DCF - Dual Cylinder Fit feature.

Also, a Cut Plane surface may interfere with the automatic exposure mode if the Cut Plane reflectivity is much different than the tube surface reflectivity. Changing to FIXED exposure mode solves this issue.

How to Set Up FIXED Exposure Mode for Any Tube Surface

To set the FIXED mode for a new tube surface, enter the FARO Laser Line Probe control by pressing VTube-LASER's Scanner Control button at the top of the viewport, then follow these steps:

1. Set the algorithm to "FIXED."
   
   
2. Aim the scanner at a tube straight and hold the scanner still in that position.
   
   
3. Press the AUTO button. Continue to hold the scanner in this position until the AUTO button re-enables.
   
   

When the AUTO button re-enables, then the setup is finished. You can press OK to exit this menu and use these new settings. These values will be stored in the VTube-LASER project file for reuse with this project later.

Two Limitations to FIXED Exposure Mode

Limitation One

The user needs to take a minute to set up the exposure setting for the current material type that is being scanned. (In our experience, no customer has objected to this extra minute of scanner setup time.)

Limitation Two

FIXED mode may not handle parts that change surface types in the middle of the part. (This is a rare situation in tube fabrication.)

PRINCIPLE 3: Scan Density of 1/16 is Good for Large Diameters

Scan Density is set in fractional values. "1/1" means all the points are being transferred to VTube-LASER. "1/16" means a 16th of the total points are transferred to VTube-LASER.

A 1/16 scan density is more than enough to measure larger tube diameters.

Not only is 1/16 enough density for scanning, but it also reduces the time required for VTube-LASER's math engine to calculate cylinder centerlines.

PRINCIPLE 4: Disable the Movement Filter

The FARO driver has a new Movement Filter option that impacts scanning even when DISABLED.

In this screen image of the Probe Management window, we show that the Movement Filter is disabled, and the value of the filter is set to ZERO. Even when disabled, this filter set to zero will block all incoming laser data.

The solution is to set the value to anything non-zero.

• Enable the option
• Slide the slider to the right
• Disable the option
• Save the change

The screen should now look something like this:

The FARO driver now allows laser data to come into VTube-LASER.