This contraption must have been lots of fun to create. The LEGO skill shines through on these modules!
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“Idea: Develop a Mindstorms/Technic creation (not competition) in which people of all building levels can participate. Each person can build one (or more) module(s). All modules will be assembled to form a large “Rube Goldberg “-ish bucket-brigade type contraption.

A Great Ball Contraption loop was assembled on FreeLug booth during LegoWorld. Thanks to a strong ItLug participation it featured 18 modules at most (Italian team had to leave on Monday morning).

The GBC worked during the 6 event days, 7 hours per day. Reliability was very good - except some errant balls of course. At the end, we noticed some gears wear and stains of black paint from soccer balls on many modules but nothing serious. My Monitor module (to be documented here later) showed that about 15 000 balls travelled the loop each day, at an average rate of 0.67 balls per second.”