Creating something as behemoth as Marble Mountain requires a lot of design patience, custom building for immediate solutions, and a bit of math and elbow grease. In this video from Ben Tardif he shows and explains the ‘loop’ system he designed to get from one part of the mountain to another while sending the marbles along an upside-down loop portion of track:
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.