OneTaskBy Tim King · Updated
Marble Run Simulator
Watch Marbles Race Down a 3D Zigzag or Spiral Track With Real Physics
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How the Marble Run works
This marble run simulator drops marbles down a track you design. Pick a zigzag or spiral track, choose how tall it is and how many marbles to send, and they roll out of the hopper one after another, clatter down the ramps and pool in the tray at the bottom. Press Release to send another batch, or click anywhere on the track to drop a single marble at that spot. The stats count how many marbles have been released, how many have arrived, how many are still rolling and how long the first one took. Drag to orbit, scroll to zoom, Save PNG to keep a picture.
Marble run simulator: how it works
A marble run is a small lesson in gravity, friction and momentum, and this one is simulated with a real 3D physics engine that runs inside your browser rather than a scripted animation. Every marble is a solid sphere with mass, every ramp is a solid surface with friction, and the marbles collide with the track and with each other, which is why a batch of ten never comes down in quite the same order twice.
Zigzag. The ramps are stacked and tilted alternately left and right, so a marble rolls to the end of one, drops off, bounces against the glass wall and lands on the high end of the next. The Ramps or turns box sets how many ramps there are, and a tall run with a dozen ramps takes a marble a good few seconds to complete. Watch the marbles bunch up on the lower ramps: the ones behind catch the ones in front on every drop, and a leader at the top is rarely still the leader at the bottom.
Spiral. The track becomes a helix winding around a central column, with a rail on the outside to keep the marbles on. Here the number sets how many full turns the spiral makes. The marbles hug the outer rail as they pick up speed, and a big batch forms a long train that snakes down the column.
Marble size changes how much the marbles jostle. Small marbles thread past each other and rarely block the track; large ones fill the ramp width and are forced to queue, which makes the zigzag drops far more chaotic. Changing any setting rebuilds the track and starts a fresh batch, and Restart does the same with the current settings. Everything is calculated locally in the page; nothing is uploaded.
FAQ
Why do the marbles come down in a different order each time?
Every marble is a solid sphere with mass and every ramp has friction, and the marbles collide with each other on the way down. Small differences at each drop compound, so a leader at the top is rarely still the leader at the bottom.
What does the Ramps or turns box control?
On the zigzag track it sets how many stacked ramps there are. On the spiral it sets how many full turns the helix makes around the column. Either way, more means a longer run.
How does marble size change the run?
Small marbles thread past each other and rarely block the track. Large ones fill the ramp width and are forced to queue, which makes the zigzag drops much more chaotic and slows the whole batch.
Can I drop a marble at a specific spot?
Yes. Click anywhere on the track and a single marble appears there. Release sends another full batch from the hopper, and Restart rebuilds the track with the current settings.
See also: all Simulations & Screensavers tools, Images, Audio, Video & Screen, PDF, SVG, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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