Rotating RDS head at a specified location

[[Je...]]

Hello all, I have hit a speed bump. I have a large part on my Contura G2 and due to it's size, the clearance planes exceed the limits of the machine travel. I can navigate around the part but I am having trouble remembering how to define a location to rotate the RDS head. The CMM, by default, is moving to +Z but hitting soft limits due to the size of my work piece. I have room on the -X and +X side of the piece to rotate but can't seem to remember how to change that without changing global default settings.

Thanks for any help

[[Br...]]

Plan>Navigation>Rotate/Swivel Position

[[Je...]]

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I had tried that but that only allows me one strategy for the measurement plan.

I have about 15 styli angles to rotate to, each will have unique location they will rotate at. I could make 2 or 3 different strategies work but only 1 is a not likely to work.

[[Br...]]

You could try turning off the automatic RDS angle change in the compatibility settings, then you just have to make sure to put a position move before the measurement strategy to make sure its clear to change angles. I've never tried this before so if you do, use extreme caution.

[[Je...]]

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Are you referring to the CAA mode of auto stylus angle calculation? We do not use that feature as accuracy suffers. All styli angles are permanent styli positions.

I was able to make it work so far using the Swivel Point feature (halfway through proving out program written offline). It allows you to select "current clearance plane" which allows the head to rotate as long as it has reached the clearance plane for the previous feature. I just have to be very careful to manage the order of rotations so the clearance distance is sufficient. Thanks for your help.

[[Br...]]

No its the optimized travel paths for Rotate/swivel setting that i was talking about.

[[Ch...]]

In the feature you can set CMM position points.... By having the feature window open on a live CMM and clicking the buttons on a joystick to generate that X Y Z location. The stylus essentially moves to that point. Recognizes a new stylus position, changes and then goes to the next feature.

[[Me...]]

I've had to do this before, but for only 2 different probe articulations. I used position points on the last feature before the appropriate angle change to get it into the right position for rotation. Then on the first feature with the new angle, I changed its clearance plane to blank, and just used position points again to get the CMM where it needs to be for the points. Rinse and Repeat for every articulation!

Interested to see if there is a better way to do this.

[[Je...]]

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I have used this method several times, however it has a serious drawback. The rotation will only work correctly if that feature is measured. Many times I may need to only run a few features or create a sub program from a few features. It is asking for trouble when multiple operators use the CMM as well.

The Swivel Position function seems to be working well so far. I am using "current clearance plane" then rotating to position 1 (0/0) The only issue I have run into is that I need to run stylus positions that are closest to perpendicular to the clearance plane first then as the angle departs from perpendicular to run them in sequence. This ensures that the stylus will be far enough away from the part during rotation that it won't contact the part. There is also a potential that if the last run feature is too far in -Z and the rotation to position 1 would cause contact with the plate. I'm working on a formula for an offset to insure that doesn't happen.