Wednesday, August 20, 2025
Constrained Parallelogram Flexure Design
I've put platforms for drive screws, anchors, drive flexures etc. on a trio of parallelogram flexures. In theory the flat bits remain parallel when the flexures move in the XZ plane.
Having a little difficulty printing it as it's bloody cold here and things tend to detach from the print bed. Hopefully soon I can give it a bit of a test.
One thing on my mind is which dimension to drive it in - motion will be in the same direction as the drive. If I drive it along the Z axis, any wobble induced by the screw drive will be constrained in the Y axis. If I drive it on the X axis, wobble will be constrained on the Y axis. If I drive it on Z, both X & Y will wobble (though Y is fairly well constrained).
If I can assume that whatever I'm driving is constrained on the X axis, it makes sense to put the Z. All the framework would need a redesign, of course, and the XY Table might as well be redesigned to take advantage of the new driving arrangement. *Sigh*
