Automatic Exposure Once by CAD

[[Mi...]]

Hi.

We have issues with exposures using the 'Automatic by CAD' Exposure time mode.

We use an ATOS 5 on our GOM Box 6130 and an ATOS 5X on our GOM Box 6235. Currently using GOM Inspect Pro Version 2021 Hotfix 1.

We always seem to be over exposed and have to revisit the scans and use 'interactively' mode and set our exposures (different values for each head, but the same values always seem to work) to get quality data.

The options 'Acquisition - Measurement - Use Automatic Exposure Once' are always unavailable (greyed out).

Does anybody have any suggestions of how we can achieve quality scan data first time through?

[[St...]]

Hello Michael Hill,

Your notice: We have issues with exposures using the 'Automatic by CAD' Exposure time mode.

Usually this is the case when the measuring setup is not well aligned, because the automatic exposure time uses the transformation of the "Virtual Measuring Room".
You can check this:

• There exists an info in the toolbox of the measurement -> Discrepancy virtual / real position
  • If this value is greater than 10.0mm, then exposure times can be computed wrongly for the background
• You can move the robot to one position and enable the live image mapping
  • So you can see the discrepancy between virtual and real position when you compare the virtual CAD to the real CAD position

To improve this behavior you should repeat the measuring setup calibration -> "Calibrate the measuring setup"

Your Question: Does anybody have any suggestions of how we can achieve quality scan data first time through?

This method "Automatic by CAD" is the correct method to compute good exposure times which take the CAD and special elements like "hemmed edges" into account.

A good compromise is made here between good measuring data and performance of the measurement list execution. 

Because you are using an ATOS 5X the most measurement data should be generated with the automatic exposure time mode "HDR+".

But compare to "Automatic by CAD", the projects are getting bigger and the measuring may take longer.

Your question: The options 'Acquisition - Measurement - Use Automatic Exposure Once' are always unavailable (greyed out).

The one-time exposure time modes computes the interactively exposure times once as proposal therefore the automatic exposure time mode must be set to "Interactively".

 

If that doesn't help, we need more information like the project to investigate the problem,

please contact the support, because it must not be the case that overexposed exposure times arises with the method "Automatic By CAD".

We are interested to solve this behavior.

 

Edited November 19, 2021

[[Mi...]]

Hi Steven.

Thanks for your reply.

I have checked a recent project and we are at a Discrepancy virtual / real position of 10.82mm.

I think because we use a special top plate on the table with tapered pins for fixture location, the measurement setup position is being accepted as good on some projects. This means that the Measurement Setup Calibration is being skipped.

I will check the behaviour on our next project and keep you updated.

[[Mi...]]

After a 3 month break in scanning we are all systems go again.....

I personally setup a project and ran Measurement Setup Calibration. I moved fixture to the calculated position, and moved part together with fixture (our alignment features are part of the fixture).

I had the same issue with extreme exposures and checked the discrepancy... WOW! As much as 16.8mm....

However, the measurement series was created off-line.....

Should I have used Smart Teach after measurement set-up calibration?

[[Mi...]]

I have had the chance to run a full project using...

Inspect Pro 2021 Hotfix 4.

I calibrated my Measurement Setup getting...

But obviously changed this because our fixture has the alignment features. So I moved the panel with the fixture like this...

Getting low quality scan points at scan M3, but position discrepancy was less than 10mm as suggested...

So checked exposures (Automatic by CAD was used when teaching). Here is what was taught....

So I switched to interactive exposures and set appropriately and scan data was satisfactory....

 

SO MY QUESTION STILL STANDS.

HOW DOES AUTOMATIC EXPOSURE BY CAD PRODUCE SUCH BAD RESULTS?

 

 

[[St...]]

Hi Michael,

sorry for the later answer.
Please contact the support, I'm interested in taking a save server record of the position with unexpected over exposures.
I need the project and one save server record of one position. The support will guide you.