The stability of the bicycle (2006)

scitation.aip.org

71 points·trymas··6 comments

For a modern / control systems perspective, check out [pdf]:

http://www.control.lth.se/media/Staff/KarlJohanAstrom/Lectur...

David E. H. Jones is a.k.a Daedalus, the crackpot inventor of the eponymous column in New Scientist and Nature in years gone by.

To those of you who are fans of Randall Munroe's What-If I heartily recommend the out of print classics The Inventions of Daedalus and its sequel The Further Inventions of Daedalus which are in a losely similar vein.

Last I heard (a few years ago) he was still alive and a documentary largely about his ingenious "perpetual motion" machines was made. I hope he's still hearty but fear he may have passed.

> It seems a lot of tortuous effort to produce in the end a machine of absolutely no utility whatsoever, but that sets me firmly in the mainstream of modern technology. At least I will have no intention of foisting the product onto a long-suffering public in the name of progress.

Bicycles are surprisingly stable as long as they are able to maintain some momentum.

minutephysics had a great video about this too:

How Do Bikes Stay Up?: https://www.youtube.com/watch?v=oZAc5t2lkvo

Well, both the article and the video say that there is more than one factor for reaching stability, not only momentum.

I think that this is the current status, knowing that the bike does not fall by the simultaneous combination of several factors. When analyzing the problem mathematically, it can be found that there are additional stability factors that do not even have direct physical meaning.

This article was originally printed in 1970.

http://socrates.berkeley.edu/~fajans/Teaching/MoreBikeFiles/...

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