Two Servos, One Axis

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Magneto
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Two Servos, One Axis

Post by Magneto »

Are there any pitfalls with using two servos to contribute to one axis of motion?

Example is one servo driving a milling quill downward and the second, driving the knee upward. Goal is maximizing available travel.

Centroid already supports dual servos for bridge mill / gantry type situations. Nice.

But this situation differs in that the proportion of travel may be different, e.g., available quill travel is 6" and available knee travel is 12".
tblough
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Re: Two Servos, One Axis

Post by tblough »

Centroid supports axis summing. I.e. if you set the Z DRO to zero and move the quill down 3", the DRO will read Z-3.000. Then if you move the knee down 2", the DRO will now read Z-1.000.

The Quill is Z, the Knee is W. You will actually need two axis drives for this, and two encoder inputs.
Cheers,

Tom
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Magneto
Posts: 15
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Re: Two Servos, One Axis

Post by Magneto »

Ah. Perfect. Thank for the clarity in that. Seems like half the battle is getting the terms right; "axis summing", in this case.
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