Robot beats Rubik's Cube, but some humans are faster

It was probably inevitable: the creation of Rubik's Cube-solving robots. Last year, two such mechanical gamesters were constructed: one by college students at the University of Illinois; another by engineers at Battelle's Pacific Northwest Laboratories.

They join several generations of chess-playing computers, swelling the ranks of game-playing machines which, perhaps, are the truest sign that the age of artificial intelligence has dawned.

Cubot, the Battelle creation, is the faster and more sophisticated of the two cube-playing robots. It can unscramble the cube in two to three minutes. While this is much faster than most humans can manage, it is well above the best human times, which are under 30 seconds.

Battelle's robot was assembled out of $7,000 worth of electronic components. It doesn't look anything like the fictional robots in ''Star Wars,'' but it rather resembles a three-dimensional letter ''U'' made of clear plastic and aluminum. It is 6 inches thick, 22 inches wide, and 17 inches high; weighs 70 pounds; and fits into a suitcase, says Robert Dyer, the head of the team of about 20 Battelle engineers who designed and built it.

''I had gotten a microprocessor chip in the mail and was wondering what I could do with it when the inspiration came,'' Mr. Dyer explains, when asked how he got the idea. ''It was just for fun. It was a chance to do something no one else had done. And, of course, I felt it would be a good public-relations demonstration of our capabilities,'' elaborates the engineer, who normally designs high-speed, automated inspection systems for military and industrial applications.

Cubot was strictly an extracurricular effort. The laboratory's only direct involvement was in purchasing the hardware. ''If you could buy this in Neiman-Marcus, it would probably cost $40,000 to $50,000,'' he figures.

When Cubot is set up, it sits on the base of the ''U'' with the two legs facing upward. The infamous cube is held in the space between the legs by two mechanical claws. A bright light illuminates one side of the cube for the machine's Cyclopean eye, a color TV-camera lens.

For most people, figuring out the moves takes the most time. Not so with Cubot. The single-purpose robot first ''memorizes'' the positions of the colored faces of the cube detected by the camera. This takes about 15 to 20 seconds. Next, a separate microcomputer determines the sequence of moves necessary to solve the cube. This takes another 30 seconds. But it takes the mechanical fingers one to two minutes to rotate and twist the cube until each of the faces is a solid color.

Although Cubot is a tour de force of technological integration, the greatest design challenge was not in the glamorous areas of computer programming or fiber optics, but in the mundanely mechanical: making the claws so they would manipulate the cube properly without breaking it.

The robot was assembled completely from stock parts, and Dyer argues that it vividly demonstrates what can now be done by the thoughtful integration of existing technologies. ''Because so many people have tried Rubik's Cube, they can appreciate it more (than the industrial applications of robotics),'' he maintains.

The engineer protests he's not a Rubik's Cube addict. The most sophisticated system his section has designed so far is one that inspects 20 bullet cartridges a second. It has also developed techniques for detecting flawed roller bearings; inspection methods for the large mirrors used in the world's first solar-power tower in southern California; and a system for detecting and sorting recycled bottles that are dirty or chipped.