48 ms·

its really awesome what they accomplished, but does the drilling diminish the achievement?

by hamitron 11y ago

deleted 11y ago
[deleted]
trevyn 11y ago
Yes! ;) I wonder if suction cups under high vacuum could work.
- Someone 11y ago
  They might work, but if, as I do not rule out, the machine uses dead reckoning (i.e. it doesn't use its cameras to detect when a face is oriented at exactly 90 degrees, but just rotates a face by what it knows to be 90 or 180 degrees), I think it would be difficult to properly set up the machine. You would have to place the suction cups exactly at the center of each face, cannot allow one cup to suck a bit harder than another, and have to make sure all faces are very close to being perfectly flat in the starting position. Edit: also, if those suction cups slip, I guess you will be looking at more Rubik's cube parts than you thought existed.
  - vectorjohn 11y ago
    I don't think you need all that. They use stepper motors so they do indeed turn exactly 90 degrees. What they would have to worry about is the suction cup not sticking perfectly. E.g. after a 90 degree turn if the momentum makes that part of the cube slide a little when they try to stop, it will introduce a small error. Maybe turning other parts of the cube would correct it.
    - JoshTriplett 11y ago
      I've seen other Rubik's cube solvers that handle this by heavily lubricating the cube, so that if the machine attempts to turn it without perfect alignment, it'll just slip into alignment rather than snapping. See https://www.youtube.com/watch?v=X0pFZG7j5cE https://www.youtube.com/watch?v=X0pFZG7j5cE for an example solver.
      - gohrt 11y ago
        Human solvers do the same.
        Someone 11y ago
        Human solvers do not hold all six sides of their cube in a tight grip. I guess it all depends on how much force it takes to turn such a stepper motor when it isn't powered.
- Practicality 11y ago
  I wonder if they couldn't make a bit of a gripper that opens and closes for each turn. Sure it would be slower but then it would match human movement.
  - cellularmitosis 11y ago
    You could, and you could also make it just as fast. Increasing the speed in the drilled approach or in the gripper approach ultimately comes down to how much power you can throw at the problem (the energy required to accelerate and then decelerate the moving parts would be the limiting factor). Its fun to imagine a situation where the level of power had been taken to such an extreme that even a slight hitch of the cube's parts would result in an explosion of tiny bits of plastic showering the room :)
waterlesscloud 11y ago
No. Not in any way.
lisper 11y ago
I think so. It's no different from, say, painting a line down the center of the pavement to help an "autonomous car" navigate. The only reason building a robot to solve a physical Rubik's cube is interesting at all is that manipulating a real cube with something like a human hand is hard. Turning something by connecting a motor directly to is is not interesting.

its really awesome what they accomplished, but does the drilling diminish the achievement?

deleted 11y ago

[deleted]

trevyn 11y ago

Yes! ;) I wonder if suction cups under high vacuum could work.

Someone 11y ago
They might work, but if, as I do not rule out, the machine uses dead reckoning (i.e. it doesn't use its cameras to detect when a face is oriented at exactly 90 degrees, but just rotates a face by what it knows to be 90 or 180 degrees), I think it would be difficult to properly set up the machine. You would have to place the suction cups exactly at the center of each face, cannot allow one cup to suck a bit harder than another, and have to make sure all faces are very close to being perfectly flat in the starting position. Edit: also, if those suction cups slip, I guess you will be looking at more Rubik's cube parts than you thought existed.
- vectorjohn 11y ago
  I don't think you need all that. They use stepper motors so they do indeed turn exactly 90 degrees. What they would have to worry about is the suction cup not sticking perfectly. E.g. after a 90 degree turn if the momentum makes that part of the cube slide a little when they try to stop, it will introduce a small error. Maybe turning other parts of the cube would correct it.
  - JoshTriplett 11y ago
    I've seen other Rubik's cube solvers that handle this by heavily lubricating the cube, so that if the machine attempts to turn it without perfect alignment, it'll just slip into alignment rather than snapping. See https://www.youtube.com/watch?v=X0pFZG7j5cE https://www.youtube.com/watch?v=X0pFZG7j5cE for an example solver.
    - gohrt 11y ago
      Human solvers do the same.
      - Someone 11y ago
        Human solvers do not hold all six sides of their cube in a tight grip. I guess it all depends on how much force it takes to turn such a stepper motor when it isn't powered.
Practicality 11y ago
I wonder if they couldn't make a bit of a gripper that opens and closes for each turn. Sure it would be slower but then it would match human movement.
- cellularmitosis 11y ago
  You could, and you could also make it just as fast. Increasing the speed in the drilled approach or in the gripper approach ultimately comes down to how much power you can throw at the problem (the energy required to accelerate and then decelerate the moving parts would be the limiting factor). Its fun to imagine a situation where the level of power had been taken to such an extreme that even a slight hitch of the cube's parts would result in an explosion of tiny bits of plastic showering the room :)

waterlesscloud 11y ago

No. Not in any way.

lisper 11y ago

I think so. It's no different from, say, painting a line down the center of the pavement to help an "autonomous car" navigate. The only reason building a robot to solve a physical Rubik's cube is interesting at all is that manipulating a real cube with something like a human hand is hard. Turning something by connecting a motor directly to is is not interesting.