Rubik’s Dice document
hackers Ben Katz and Jared Di Carlo have smashed the earlier document for fixing the Rubik’s dice robotically. Their machine solved the puzzle in zero.38 seconds—a 40-percent enchancment over the earlier document of zero.637.
“We observed that the entire quick Rubik’s Dice solvers had been utilizing stepper motors and thought that we might do higher if we used higher motors,” Di Carlo wrote in a weblog submit.
A custom-built motor controller permits a single flip of the Rubik’s Dice to be accomplished in round 10 milliseconds. With a a typical Rubik’s Dice resolution taking 19 to 23 turns, that ought to enable a dice to be solved in round zero.25 milliseconds—however the pair say the present iteration of the machine makes a transfer each 15 milliseconds as a substitute.
“The machine can positively go sooner, however the tuning course of is basically time consuming since debugging must be finished with the high-speed digital camera, and errors usually break the dice or blow up FETs,” Katz wrote on his weblog. “In the meanwhile, Jared and I’ve each misplaced curiosity in enjoying the tuning sport, however we would come again to it will definitely and shave off one other 100 ms or so.”
Whereas a human participant could be inclined to loosen the dice as much as make it simpler to show, Katz says they discovered the alternative method works higher for robotic fixing.
“When the dice is free (like it might be if an individual had been attempting to resolve it quick), the outer faces simply cam outwards whenever you attempt to flip the middle faces rapidly,” Katz writes. “It took tightening the dice manner previous what intuitively felt acceptable with a view to cease the camming motion from taking place.”
To detect the present state of the dice, Katz and Di Carlo acquired a pair of Ps three Eye webcams for $7 every. They positioned them at reverse corners of the dice, permitting every digital camera to look at three faces.
The cameras had hassle distinguishing crimson and orange faces, in order that they painted the orange faces black to make them stand out higher.
“The software program identifies all the colours, builds an outline of the dice, and passes it to the min2phase solver,” Di Carlo writes. The answer is then despatched out by way of a serial cable to the six motors, one for every face of the dice. The entire course of—from capturing the picture to sending the directions to the motors—takes round 45 milliseconds.
There’s much more element on the venture on Katz and Di Carlo’s weblog posts.
Itemizing picture by Ben Katz