PRBS Generator

PRBS Generator is a piece of kinetic art that mechanically generates a Pseudo-Random Binary Sequence (PRBS). When I learned about PRBS at my university, I designed a mechanism for it on 10 January 1987. The mechanism was as simple as the algorithm to generate a PRBS. It uses a shift register, where a new bit is the exclusive OR (XOR) of two earlier bits. I implemented this mechanism 37 years later, where the shift register is a set of seven "bits" on a rotating disk. At one point, a bit flips when its neighbour is "0", whereas it stays the same when the neighbour is "1". The flipping is pushed by gears at the bottom of a bit. The flipping is blocked when the neighbour is in its "1" state. Then the magnets decouple the rotation of the gear from the bit. The mechanism cycles through 127 different seven-bit sequences, only skipping the "1111111" sequence.

The mechanism uses 28 3x3-millimeter disk magnets: https://www.supermagnete.de/eng/disc-magnets-neodymium/disc-magnet-3mm-3mm_S-03-03-N and eight M3 flat cheese head screws.

Watch the YouTube video.
Read at the Shapeways Forum.
Read more at the Non-Twisty Puzzles Forum.

Please order a 3D-printed do-it-yourself puzzle kit from Shapeways at this page (check with Oskar about screws and stickers), or contact Oskar directly if you are interested in obtaining a fully colored, stickered and assembled sample of this puzzle.