Using the architecture for building machines

General
1

I am currently building the microscope while doing the FabAcademy.
With some friends, we were thinking about a solution to produce fully 3D printable machines that make machines including high precision ones.

I find the design of the stage extremely interesting for that purpose.
The design that was built is the following. It is very nice because there is no z displacement but it is problematic because the range of motion is very small compared to its size :-5mm to +5 mm with the full device being 30 cm wide.
It is based on the thesis of Shoryar Awtar (2004)

The idea would be to fix a bed to the stage and put a drill on the z axis (or an extruder) to build small but precise parts at first with very limited sourced parts.

I would love your feedback and suggestions on that idea.

2

make machines including high precision ones.
How precise are you aiming for? 2PP is down to single microns. UV and laser scintering low hundreds and fused deposition high sub-mm. The design goal of the OpenFlexure stage was optical microscopy where you usually travel to a point of interest and focus around it and neighbourhood. a 3D printed part is more continuous tracing along a geometric topology. You get trade offs with travel speed vs point accuracy (spatial resolution), fabrication speed vs material handling, and correcting for drift/shrinkage. It may well be you use the OpenFlexure stage as a post-production QA/inspection rather than tie yourself in engineering knots trying to integrate the two.

3

The lack of Z displacement is really nice in that design - but it comes with a significant cost, which is Z stiffness. Because the design is quite wide and flat, I strongly suspect if you mounted a drill (or a bed) on such a system, it would wobble about and lose precision. The OFM mechanism doesn’t have perfectly planar motion - but it is axially quite stiff, which is important for maintaining focus.

If you’re thinking of using the OFM design for this, I’d worry about load capacity; the Z axis can handle an objective (which is heavier than a couple of grams, but much lighter than a drill) but bear in mind that’s non-contact. The sideways forces you get from a drill/router would probably rip the stage apart.

I like @drllau’s suggestion of polymerisation; that potentially works quite well in a microscope, if you can find the right optics, and would be a good fit for the OFM. You’d probably want to add some image-based feedback to improve positioning precision, but I’d be optimistic that this could make micron- or even submicron-sized features, with the right optics and control scheme.

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Yes 2PP can get to sub-micron nano structures (middel center-right) but
a) they’d have to be compact as printing speed suffers
b) the polymers are often trade secrets so open question whether they’d impact biological samples
c) you’d want to look into self-assembly substructures in parallel otherwise too slow

But in theory yes … you can use the stage and have one optic path for precision guidance/feedback (laser inferometry?) and the second path for deposition beam so long as you control for all the other variables like thermal expansion, vibration, calibration drift, etc