LEGO Mindstorms Sudoku Solver

Swedish hacker [Hans Andersson] is no stranger to puzzle-solving robots. His prior work, A Rubik’s cube-solving robot called Tilted Twister, made waves through the internet last year. [Hans’] latest project only has to work in two dimensions, but is no less clever. This new robot, built around the LEGO Mindstorms NXT system, “reads” a printed sudoku page, solves the puzzle, then fills out the solution right on the same page, confidently and in ink. It’s a well-rounded project that brings together an unexpected image scanner, image processing algorithms, and precise motor control, all using standard NXT elements.

The building instructions have not yet been posted, but if the video above and the directions for his prior ’bot are any indication, then we’re in for a treat; he simply has a knack for explaining things concisely and with visual clarity. The source code and the detailed PDF diagrams for Tilted Twister are as gorgeous as his new robot’s penmanship.

[thanks Eric]

Automated Paintball Sentry

Reader, [Ben Godding], sends in the video for his senior design team’s automated paintball sentry. The frame is made of plasma cut aluminum. The paintball gun uses a custom hopper mounted remotely from the gun body. It has two webcams offering a 160 degree field of vision, and the image processing is done by a dual core pentium CPU booting windows xp off a compact flash card. The computer interfaces with the 1/4scale RC servos using a PIC24. The paintball sentry can either be configured via a computer GUI when a monitor is available or a baclkit keypad and 4×20 charachter display in the field.

Related: [Jared Bouck]’s paintball gun turret