Bicycle Stability -- new research results->
Submitted
by
MITguy21
MITguy21 writes "Researchers look deep into the physics of bicycle self-stability...it's not simple! From their abstract:
"Long known, but still amazing, is that a moving bicycle can balance itself. Most people think this balance follows from a gyroscopic effect. That's what Felix Klein (of the Klein bottle), Arnold Sommerfeld (nominated for the Nobel prize 81 times) and Fritz Noether (Emmy's brother) thought. On the other hand a famous paper by David Jones (published twice in Physics Today) claims bicycle stability is also because of something called "trail". Trail is the distance the front wheel trails behind the steer axis. The front wheel of a shopping cart castor trails behind its support bearing and so must a bicycle front wheel, Jones reasoned. Jones insisted that trail was a necessary part of bicycle stability.
"We suspected that such simple images were missing at least part of the picture.
"To find the essence of bicycle self balance we looked at simpler and simpler dynamical models until we found a minimal two-mass-skate (TMS) bicycle that theory told us should be self-stable. This bicycle has no gyroscopic effect and no trail. We built a bicycle (of sorts) based on the theory to prove the point."
Several news sites have picked up the story:
http://news.google.com/news/search?aq=f&pz=1&cf=all&ned=us&hl=en&q=riderless+bicycle
This BBC audio interview starts at about 12 minutes in:
http://www.bbc.co.uk/iplayer/episode/p00fwm7k/Science_In_Action_14_04_2011/"
Link to Original Source
"Long known, but still amazing, is that a moving bicycle can balance itself. Most people think this balance follows from a gyroscopic effect. That's what Felix Klein (of the Klein bottle), Arnold Sommerfeld (nominated for the Nobel prize 81 times) and Fritz Noether (Emmy's brother) thought. On the other hand a famous paper by David Jones (published twice in Physics Today) claims bicycle stability is also because of something called "trail". Trail is the distance the front wheel trails behind the steer axis. The front wheel of a shopping cart castor trails behind its support bearing and so must a bicycle front wheel, Jones reasoned. Jones insisted that trail was a necessary part of bicycle stability.
"We suspected that such simple images were missing at least part of the picture.
"To find the essence of bicycle self balance we looked at simpler and simpler dynamical models until we found a minimal two-mass-skate (TMS) bicycle that theory told us should be self-stable. This bicycle has no gyroscopic effect and no trail. We built a bicycle (of sorts) based on the theory to prove the point."
Several news sites have picked up the story:
http://news.google.com/news/search?aq=f&pz=1&cf=all&ned=us&hl=en&q=riderless+bicycle
This BBC audio interview starts at about 12 minutes in:
http://www.bbc.co.uk/iplayer/episode/p00fwm7k/Science_In_Action_14_04_2011/"
Link to Original Source
