A bicycle is composed of four rigid bodies: the two wheels, the frame, the front fork (the steering column). Each adjacent pair of parts is connected with a joint that allows rotation along a defined axis, and the wheels are connected to the ground by requiring that their lowest point must have zero height and no horizontal motion (no sliding).

So the simulation has a lot of simplifications from reality, and the picture tells us more about the simulation model than it tells us about the real world. It is a pretty picture, though.

Here's the paper reference:

Cook, M. 2004. It takes two neurons to ride a bicycle.

(I couldn't get it from the Cook's Caltech site, but I found a copy elsewhere.)

[–] Eh_I@lemmy.world 2 points 3 days ago (1 children)

The interesting thing in this situation is that it curved at all.

[–] Sims@lemmy.ml 3 points 1 day ago* (last edited 1 day ago)

The fork is bend so the bike automatically counter-steers against gravity. As long as the speed is high and the wheels are spinning (centripetal/symmetry forces), it will tend to steer in a straight line. So the spinning wheel and the bend, makes the bike run upright. The bend has a name, but I forgot..