In June 2023, 21-year-old Max Park set the Guinness World Record for the fastest time to solve a Rubik’s cube, at just 3.13 seconds. And while that’s a blisteringly fast time for a human, it’s a snail’s pace compared to the world record for fastest cube-solving by a robot.
Last month, Mitsubishi Electric’s TOKUI Fast Accurate Synchronized Motion Testing Robot (TOKUFASTbot) successfully shaved off 0.075 seconds from the previous robot speedcubing record (set by MIT students in 2018), solving the 3x3 block puzzle cube in 0.305 seconds, which is roughly the length of time it takes to blink. The Mitsubishi team, composed entirely of young engineers, had been working on the project on a voluntary basis since September 2022.
The powerful robot uses an AI-powered color-recognition algorithm and high-speed motors to rotate the cube 90 degrees in 0.009 seconds. The engineers used motion-control technology, originally developed for the wiring of Mitsubishi-manufactured appliances such as air conditioners, to ensure that the cube was rotated precisely and kept in alignment.
As the robot had difficulty distinguishing between red and orange, this became a particular focus for training the AI program, as did learning to recognize colors when the blocks were moving or the camera system was in shadow. However, once the color-recognition hurdles were overcome, it was a matter of milliseconds for TOKUFASTbot to identify the precise mixed-up color arrangement and calculate the most efficient rotations to make each side of the cube a single color.
A puzzle fit for a bot:
- *The progression of robot speedcubing world records is truly phenomenal. In 2009, the world record stood at one minute and four seconds. By 2016, a robot had cut down that time to less than a second, with subsequent attempts redefining the scope of the record to mere tenths of a second.
- *TOKUFASTbot’s record attempt was undertaken on May 7, 2024, in Hyogo, Japan. The team needed two tries to claim the world record, as the cube jammed the first time due to the incredibly high rotation speed.
- *When Hungarian architecture professor Ernő Rubik developed the puzzle cube in 1974, it took him a month to solve it, which is perhaps not surprising considering there are over 43 quintillion different ways to arrange the nine colored squares on the cube’s six faces. It is now the world’s most popular puzzle toy.
