Loose belts during calibration

[dlang]

and I just made a post about this

New source of error

@bar I was wondering what the difference is between the triangle we are calculating (as if the belt were really a straight line from the anchor to the Z axis of the bit) vs reality (where the belt is a straight line from the end of the anchor plastic to the end of the arm) so I did a quick onshape doc to play around with this and it looks to me like this can be enough of an error to be significant when near the anchors if the arm length is 150mm, the Z offset is 100mm, and the true x/y distance…

the belt length calculations don’t take into account the fact that the belt is
not making a perfect triangle. once you add that, you add a noticable amount of
error that seems to correlate with this pattern.

David Lang