Once upon a time
Long back when I was a little kid, I paid a visit with my parents to the Verkehrhaus (museum of transport) in Luzern, Switzerland. I remember that I was very impressed by the following marble run machine:
My own machine
I wanted to build my own machine ever since, but it’s only now (30 years later) that I’ve finally found the time for it.
I’ve mainly used my Lego Mindstorms and Lego Technics for it. And even though it is not as impressive as the marble run in that swiss museum, I’m still quite happy with it.
Overview
Caterpillar track
The caterpillar track transports the balls to the first slide.
Donkey Kong
Evil Donkey Kong tries to grab the balls (his arms are connected to a motor), but he never succeeds…


Crane
The crane grabs the marbles and pushes them gently up the slope.


Seesaw
The seesaw is pretty cool. It uses pneumatic elements from the 8868 Air Tech Claw Rig set. There’s a compressor motor that provides a steady flow of air. This causes the seesaw to work: when one goes up, it triggers a lever that causes itself to go down and the other one to go up.
And next to that it also triggers the pneumatic elements under the slopes. These slopes slowly transport the marbles back to the caterpillar.



Video
This video brings it all together.
Similar projects
If you liked this project, you might also like some of my other Lego Mindstorms projects:
- The M&M sorter
- The coin pusher
- The paper plane launcher
- and many more…