The project is the work of Human Controller, who posts his creations on his YouTube channel. The floating Rubik's Cube began life a year ago when he upgraded a standard version of the toy with a 3D-printed core, servos, wiring, and batteries so all of the sides can spin.
Technically, this Rubik's Cube doesn't really solve the puzzle. It uses an Arduino board to record all the movements that were performed as the colors are being scrambled. These are then repeated in reverse, leading to the completed puzzle. Rather than the device precariously rolling around on a table as it twists and turns, the latest version now floats in mid-air as it solves itself. The trick is performed using some magnets hidden inside the cube and a magnetic base. You can see more photos and videos showing the internals of the cube and its workings in this post
from Human Controller. In March last year, Massachusetts Institute of Technology robotics student Ben Katz and software developer Jared Di Carlo crafted a machine that can solve a Rubik's Cube in a record 0.38 seconds, beating the previous machine record of 0.637 seconds. The human record for solving one of the puzzles is 3.47 seconds, which China's Du Yusheng set in 2018.