Double Ball Coaster

This ball roller coaster has two independent tracks. The outer track keeps the large red ball circulating around over and over automatically, while the inner track circulates the small red ball. Two motor-powered lifts raise the balls from the bottom to the top, and the distance sensor and color sensor are used to detect when the balls have finished a lap and need to be raised again.

Building Instructions

Inner Track

Outer Track

Double Ball Coaster