2 HN users recommended this demo1 month2013–2019score 1
Years with an HN recommendation, 2007–2026
HN commenters cite it as the author's own demonstration of research showing that bicycle stability is not explained by gyroscopes.
Arend Schwab demonstrates a research bicycle, the two-mass-skate design, that balances itself without gyroscopic effects or trail. It challenges the common explanations for why a moving bicycle stays upright.
“Explanation of the research in question behind this article, as well as a demonstration of the bike they based the research on.” (HN, 2013)
We do know, here is the paper that the journalist refers to: [link] And here is a great video by the author: [this video] Short answer: "a bicycle should turn into a fall."
Author's video showing a bicycle should turn into a fall.
[1] Explanation of the research in question behind this article, as well as a demonstration of the bike they based the research on. They very clearly describe (at the end of the video) that even with gyroscopic and tracking forces removed, the two most important factors are where the center of gravity is, and the tendency to turn into a fall (arguably just the second, but it is caused by the location of the center of gravity with regards to the pivot). [1] [this video] Edit: more info on the TMS (two-mass skate) bike at its wikipedia page: [link]
Demonstrates the research bike stable without gyroscopic or trail effects.
I don't think either of us understands that experiment. Fortunately, actual engineers have proven that bicycles don't stay upright from gyroscopic effects. [0] [1] If you want to experiment, try riding a bike that can't be turned. You might want to wear a helmet for that one. [0] [link] [1] [this video]
There was still active research into why bicycles are stable as recently as 2011. Here's a talk about that research: [this video] If the bicycle was some sort of "obvious" machine, people wouldn't still be studying the basic stability mechanics 200 years later. Very few things are as simple as they seem. Even levers can get a bit complicated.
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