[Updated: Mar 17] — A Cubestormer 3 robot based on a Galaxy S4 Android phone and eight Linux-driven Lego Mindstorms EV3 bricks has smashed the Rubik’s Cube solving record.

The Cubestormer 3 was formally unveiled Mar. 13 at the Big Bang Fair in Birmingham, UK, and was expected to beat the 5.27 second record set by the Cubestormer 2 in 2011 when it competed on Mar. 15 in a Guinness World Records competition. The cube-solving robot was developed over a period of 18 months by ARM principal engineer David Gilday and Mike Dobson, a security systems engineer for Securi-Plex, with backing from ARM.

Speedcuber (2010)

Gilday first entered the competition for Rubik’s Cube solving robots in 2006, with a robot running on an ARM11- and Symbian-based Nokia N95 smartphone. He then unveiled an upgraded Speedcuber design in 2010, winning an ARM developer conference competition by solving a 3x3x3 Rubik’s Cube in 12.5 seconds. The robot combined a 1GHz, ARM Cortex-A8 based HTC Nexus One smartphone running Android 2.1 with a Lego Mindstorms Robotics Kit.

Gilday then teamed up with Dobson, one of his chief rivals in cube-solving competitions, who had introduced his Cubestormer in 2010. In 2011, Gilday told Wired that he joined with Dobson to combine his software skills with Dobson’s mechanical prowess.

Together, they developed the Cubesstormer II, which won the Guinness World Records event for the Rubik’s Cube in 2011 with 5.27 seconds. The fastest human record is 5.55 seconds, set by Mats Valk of the Netherlands in 2013. The Cubestormer II was built with a faster Lego Mindstorms NXT kit, as well as a Samsung Galaxy S2 smartphone, which runs Android on a dual-core, Cortex-A9 Samsung Exynos 4 system-on-chip.

Cubestormer 3
(click image to enlarge)

The Cubestormer 3 runs on a Samsung Galaxy S4, which is in turn based on a Samsung Exynos 5 SoC, combining four Cortex-A15 cores and four Cortex-A7 cores in a Big.Little configuration. The device also moves up to a Lego Mindstorms EV3 Robotics Kit, which runs Linux on an ARM9-powered “brick” computer.

The robot uses eight EV3 bricks to perform motor sequencing and control with the help of four robotic arms. As in the previous cube-solvers, the Cubestormer 3 uses the phone to photograph each side of the cube, and then computes the fastest technique for rotating the cubes so each side shows a single color.

Two views of Cubestormer 3
(click images to enlarge)

The Cubestormer 3 also incorporates improved mechanics, such as a precision independent braking system. In addition, the software has been optimized to exploit the faster processors in both the smartphone and Mindstorms EV3 brick, and the increased mechanical flexibility of the robotic arms.

“We are very confident the robot will break the record,” stated Dominic Vergine, head of corporate responsibility at ARM. “The new robot can think three times faster than its older brother.”

That confidence is based in part on a demonstration last month of the Cubestormer 3 solving the Rubik’s Cube in 3.426 seconds. The demonstration was held at the Lego World Fair in Denmark, but was not an official Guinness event.

Gilday also entered two other ARM-based robots in the weekend’s cube-solving competition. The MultiCuber 3 attempted a 4x4x4 cube-solving record with a Huawei Ascend P6 smartphone based on Hisilicon’s K3V2E SoC. Gilday’s MultiCuber 999 robot, meanwhile, was the first robot to attempt solving a 9x9x9 cube. The problem required processing solution possibilities running to 278 digits. The MultiCuber 999 is based on a Galaxy S3 smartphone running a quad-core version of the Exynos 4.

“Our real focus is to demonstrate what can be achieved with readily-available technology to inspire young minds into taking a greater interest in science, technology, engineering and mathematics,” stated Gilday. “While the human brain is still far more powerful than any processor, it would be fantastic to see technology with real human-kind benefits being created by someone inspired by seeing Cubestormer 3 in action.”
 

And the winner is…

Mar 15 update: “The ARM-powered Cubestormer 3 robot has smashed the Guinness World Record for solving a Rubik’s cube, recording a time of 3.253 seconds at the Big Bang Fair in Birmingham, UK,” stated a post to ARM’s YouTube channel. A video of the accomplishment appears below.

Cubestormer 3 smashes Rubik’s Cube speed record
Source: ARM, YouTube
 
Further information

More information on the Cubestormer 3 may be found in ARM’s Cubestormer 3 announcement. More on the Mar. 15 competition may be found at The Big Bang Fair website. The fair will be held at the NEC in Birmingham, UK.