neat , amamzing what we can do with crap material and a microcontroler , i’ve started mine before the py was availlble , i’m working with arduino , but impresive design and result , my two thumbs up
Next it needs an precision surface sensor so that it can learn the kinematics of the motion platform, eliminating the need to place the axes with precision.
This is, I think, particularly interesting for reprap and other projects that seek to print printers. Using a bit of mathematical heavy lifting to compensate for, shall we say, “rougher” hardware.
The math for this design isn’t any more complex for the math on a delta bot.
very interesting… you could go 3 steps beyond this and use a Stewart/Gough platform. Would make for a very stable platform, and interesting prints since it has 6 degrees of freedom…
@Rodger_Evans being able to tilt the print head isn’t very useful (not nearly as much so as being able to tilt a drill or router)
Yes, I see your point, but you could make many structures without needing support (like arms on a figure). Writing the g-code would be tricky, but I bet the CNC mill coders have already had to figure this out.
Ahh, see, I thought you meant to tilt the print head, but you mean to tilt the print. That WOULD allow for a lot of geometry that can’t be done otherwise without support material. You’re right about the g-code being tricky. There aren’t many (any?) free or open source controllers for 4+ axis machines, and that’s what you’d need if you wanted to print in this way.
At some point I’ll be looking at the geometry for Stewart/Gogh platforms (are also called hexapods), there are publications with the geometry explained, it is just more then a hour read can grasp. Any comments on good linear actuators? I’ve been thinking that the platform could be printed, but the actual actuators would be tricky.
How might a Stewart platform be better than the delta-bot approach like what is taken by the Rostock or DeltaMaker projects?
I think the delta configurations have the capacity to tilt the head so they could lay down lines out of the plane of build platform, or even non-planar paths, but I don’t know if there are yet any toolpath generators that are smart enough to use that ability.
First, thanks for the links, I’ve not heard of that type of printer before, very interesting. First off, a hexipod has 6 degrees of freedom, not sure if that is better or not, but it is more. I was thinking of moving the object, not the head so the printed object could be twisted and angled. The delta can angle the head, but not with complete freedom, and like the comment above, I can’t see any benifit to the head beaing angled.
Finally, with a hexipod, the base is very rigid. You find these used with telescopes and other optics as well as flight simulators etc… Althoe, I’m not sure if it is a bad idea to move the object instead of the print head.
Relatively speaking, I don’t think there is any spatial difference between angling the head or angling the build platform. I think a delta configuration does lack the roll control that a Stewart platform provides, but if it’s controlling the head rather than the build platform I suppose that doesn’t matter, since the nozzle is point-like.
A moving platform can cause problems for large parts as the center of gravity rises above the platform, the acceleration of the platform can break the part loose. For small platforms that’s not really a problem though.
A couple guys at my local maker space started on laser cutting the parts for a Quantum Delta last night, so I suppose I’ll have the chance to see an inverted delta soon: