Something I've wanted to try for years is what about a Lego refraction distillation tower? Similar to how oil refineries use a tower to sort hydrocarbon compounds by length based on their volatility. Except in this case instead of using heat we would use air blowing upward in a long tube to make the pieces "volatile". Picture a 6" diameter clear tube stretching floor to ceiling with a powerful blower at the base. Or a smaller version could be prototyped using an air popcorn popper with the heating element disabled.
Essentially it would sort pieces according to their free-fall terminal velocity. You could exploit the Venturi effect to make the bottom of the tube have a higher velocity than the top, or simply add bleed-air holes at progressive levels. There could be take-off doors at different levels of the tube. A nice property is that if the ingress and egress mechanisms are designed elegantly, it could run continuously.
(Although, that last point is one reason I've never built it: it seems like there would be a fine line between "air powered sorter" and "air powered rock tumbler" and I worry it could wear the corners of all my Lego bricks if it goes wrong.)
Another potential issue is that there might not be much logical relationship between the pieces which share similar terminal velocities, and different pieces may have different or metastable terminal velocities depending on initial orientation.
Obviously this wouldn't be a perfect sorter, but it could be a good pre- or post- sorter for your visual system. And for my purposes it might work well since instead of adapting the system to suit my sorting preferences I could simply train my sorting expectations based on what I learn the machine tends to sort together.
Hmmm now that I have an industrial dust collector installed in my workshop, I actually already have the bulkiest / most expensive part of this invention. I just need a tall acrylic tube and I could try this!
How do asymmetry and angular momentum affect this? Or how do they affect terminal velocity in general? (For example, what can happen to a Lego plate which has a very different terminal velocity in one orientation than in another?)
Essentially it would sort pieces according to their free-fall terminal velocity. You could exploit the Venturi effect to make the bottom of the tube have a higher velocity than the top, or simply add bleed-air holes at progressive levels. There could be take-off doors at different levels of the tube. A nice property is that if the ingress and egress mechanisms are designed elegantly, it could run continuously.
(Although, that last point is one reason I've never built it: it seems like there would be a fine line between "air powered sorter" and "air powered rock tumbler" and I worry it could wear the corners of all my Lego bricks if it goes wrong.)
Another potential issue is that there might not be much logical relationship between the pieces which share similar terminal velocities, and different pieces may have different or metastable terminal velocities depending on initial orientation.
Obviously this wouldn't be a perfect sorter, but it could be a good pre- or post- sorter for your visual system. And for my purposes it might work well since instead of adapting the system to suit my sorting preferences I could simply train my sorting expectations based on what I learn the machine tends to sort together.
Hmmm now that I have an industrial dust collector installed in my workshop, I actually already have the bulkiest / most expensive part of this invention. I just need a tall acrylic tube and I could try this!