Robot Sets New Rubik’s Cube Speed Record, Completing the Puzzle in 0.305 Seconds
A team of Mitsubishi engineers harnessed high-speed motors and an A.I. algorithm to eclipse the previous record, set six years ago
Quicker than a snap of the fingers it doesn’t have, a robot has shattered the world speed record for solving a Rubik’s Cube, completing the puzzle in just 0.305 seconds.
This record time is roughly equivalent to the length of a human’s blink, which usually takes between 0.1 and 0.4 seconds.
Built by a team of engineers from Mitsubishi Electric, the TOKUI Fast Accurate Synchronized Motion Testing Robot (TOKUFASTbot) edged the previous record—set by a robot developed by MIT students in 2018—by 0.075 seconds.
“I checked the videos of the previous record holder, and I felt that the motor we have is better than theirs,” Tokui, an engineer at Mitsubishi and the team’s lead, tells Guinness World Records’ Masakazu Senda. “So I was confident that we can beat them with speed.”
Since its invention in 1974, the Rubik’s Cube has exploded in popularity, eventually becoming the most popular puzzle toy in the world. At its core, the puzzle is simple: Each of the cube’s six faces has nine colored squares, and the solver must rotate the toy in a way that gets every side to have a uniform color. But even on the standard three-by-three cube, the colors can be arranged in more than 43 quintillion different ways.
Erno Rubik, the creator of the cube, was also the first person to solve it—and it took him an entire month. Since then, people have tried to complete the puzzle in ever-faster times, prompting the emergence of a competitive sport known as speedcubing. And alongside humans tackling the challenge, engineers have developed cube-solving robots.
TOKUFASTbot’s rotational mechanism is able to complete a 90-degree turn of the cube’s edge in just 0.009 seconds. This quickness is made possible by powerful and highly precise motors, as well as a color-recognition algorithm that uses artificial intelligence, according to a Mitsubishi statement.
Once the machine identifies the mixed-up cube’s pattern, it calculates the quickest route to its solution. It was sometimes challenging for the robot to distinguish between the cube’s red and orange squares. Other times, shadows in the room affected the hues and made color recognition difficult.
But in the end, it was the TOKUFASTbot’s own blistering speed that posed the biggest obstacle. During the first attempt to set the world record—which the team had to do within just one hour total—the machine was moving so quickly that the Rubik’s Cube itself was unable to keep up, and it became jammed. After engineers spent roughly 20 minutes fine-tuning the robot’s mechanisms, the second attempt was successful: The robot clocked a time faster than during any practice run, achieving the heralded world record.
“Shaving off time as much as possible was difficult, but it was fun at the same time. I never had issues with motivation through the project,” Tokui tells Guinness World Records.
The world record for a robot solving a Rubik’s Cube was set at one minute and four seconds in 2009. Then, in 2016, a robot eclipsed the one-second barrier for the first time.
For human solvers, the world record stands at 3.13 seconds, set in June 2023 by 21-year-old Max Park.
Usually, the technology used by Mitsubishi’s engineers would be harnessed for fine-tuning wiring in appliances such as air conditioners and ventilation fans, per the Asahi Shimbun’s Satoshi Seii and Ryuichiro Fukuoka. But according to the company, attaining this goal was an above-and-beyond effort by a dedicated group of engineers who began developing the robot in September 2022, after seeing the potential for Rubik’s cube gold.
“To demonstrate our technical capabilities in achieving high-speed, high-precision windings, which are key to increasing the productivity and efficiency of motors used in many of our products, our young engineers voluntarily worked to set the world record, resulting in a Guinness World Records title,” Yuji Yoshimura, a senior general manager at Mitsubishi’s component production engineering center, says in the company’s statement.