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Scanning Planes/Cookbook


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So I've followed cookbook instructions on scanning planes but I still get the error that comes up and says "The sensor did not carry out the measurement with the expected measuring force."

Anyone have any advice? It seems to be an incorrect filtering problem because it doesn't error out of filters and outliers are turned off..
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I notice that it will also depend on probe size as well as speed. We work on small parts a lot and when we scan for profile using small probe size (.6mm 1.0mm) we need to slow it down a little more to help with it. It also is somewhat dependent of feature configuration as well. This has seemed to work for us.
Were your paths generated form the CAD model or from actual physical geometry?
If your woking from only cad it's possible to have what I refer to as "competing realities" that can generate this very error.

Suppose that the manufactured part physically differs for the CAD model in such a way that the top plane is actually .015" lower, or higher than where the calculated scanning path was on the model?
When Calypso then goes to scan that plane, the probe is going to either come into contact much sooner, or perhaps not at all.
Unexpected probing forces error will ensue.

Otherwise, ensure your always probing both slow enough and with sufficient point density.
An active sensor like VAST/XT can actively (and rather quickly) follow geometry deviations without having to move the machine axes. Thus it can keep a constant probing force even at higher scanning speeds. A passive XXT can't do that and must use the machine axes instead. But if scanning speed is too high, the axes aren't fast enough and the probing force goes off limits. That's when you get that error.
I would not want to trust the results with them off. If you turn them off then you will end up with more noise in your data.

If the problem is not being able to scan the features because they are in the wrong position, you may need to consider adding in an intermediate step to align to the feature prior to scanning it.

Keep in mind the cookbook has a part in the beginning that specifies all the 'recipes' are intended as starting points and individual results may vary. Were you having these problems prior to 'fixing' your filtering and outliers?
I am fairly confident that it is just a speed issue because I have a Passive RDS-CAA head, I am scanning too fast. As far as it being an issue historically...It's hard to recall because I've programmed with XT, XTR, XXT, & now RDS-CAA and I've only been using the Cookbook for about 4 years now. I've had the error come up often, usually I've corrected it by slowing down.
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