Good observation. It's clearly not a stock out-of-the box Rubix's Cube. My recollection from childhood was that it took considerable tuning (with sandpaper) and

Good observation. It's clearly not a stock out-of-the box Rubix's Cube. My recollection from childhood was that it took considerable tuning (with sandpaper) and greasing afterwards to loosen one up to move smoothly. From the comments : "With a bit of practice and almost any other brand of Rubix cube (the Rubix branded ones suck)" It's interesting that the bot rotates the centerpoint, while human hands would grasp the edges and compress the blocks together. The slow-motion camera .05x view was amazing. The inertia of the blocks is evident. We see this sort of problem in motion control routines for robots. A motion needs an acceleration/deceleration rate or parts get over-stressed and tend to blow up, or at the least overshoot targets.