sensor did not carry out the measurement?

[[Ri...]]

This is happening far to often. I have programs running features for I dont know how long and now this comes up randomly, and when it starts, it doesn't stop.
It is creating a large amount of lost time on the CMM because the CMM now has to re-run the feature in ultra slow motion "Optimizing".

What could be causing this?

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Calypso v7.0.12
RDSCAA Vast XXT
Contura 2014 (quite large table)

[[Ro...]]

Hi Rick,
The most common reasons for this in my experience are one of a few things...

The surface being measured is moving and the pressure from the sensor isn't consistent. This has happened to me on parts that are flexible material, like plastic, or parts that are not securely fixtured and are rocking, moving, etc.

The surface being measured isn't located close enough to the nominal location. I've had this happen when a scan gets too close to an edge and/or is trying to measure something that is far enough out of position that the sensor doesn't have consistent pressure.

Scanning too fast.

Maybe it's one of these or a combination of them.

[[To...]]

If you can't live with scanning optimization, I find that if I take some preliminary points to help locate the feature first, and then reference that info when I run the actual feature, I have less of these types of messages. For example, there are several ways to take 3 or 4 touch points in a circle first, then go back in and scan the circle based on what the points found first.

You can also de-activate Scanning Optimization if you feel the data is "good enough" from the original scan.
Resources > Compatibility settings for this program > Scanning Optimization > Off

[[Ri...]]

I'm am going to attempt to turn off Scanning Optimization first.
This happens on too many parts and with too many styli.
Fixturing is not the problem in any of our products.
The only thing I can think of is the one sided tolerancing.
Ex: Ø12.005 +.0045, +.001
The model will be nominal (Ø12.005), they are almost always customer supplied.

Also note, when the "sensor did not carry out the measurement....." pops up in the Status Window, it doesn't always re-scan.

[[To...]]

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I've never seen a plane or line re-measure itself but I do see the message quite often, usually at the beginning of the scan. Considering the beginning of a scan is masked, I usually don't care about those.

[[Je...]]

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Hey Rick. I worked with an RDS passive head for quite a while, and I feel your pain about the scanning optimization. It sounds like you're getting some good advice on this thread about how to work with it. I do think that the one-sided tolerancing may be a factor. If it results in the actual value being quite different from the nominal value, the software will compare the two and be quick to blame the scanning speed and slow it down.

Jeff Frodermann
Meier Tool & Engineering
Anoka, Minnesota
.
.

[[No...]]

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Maybe an older measurement plan? When Calypso introduced this feature, it only applied to new programs. The message displays every time, but in older programs you first have to activate rescan in the compatibility settings.