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Why didn't Google hire me to build this!!!???

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I just came across this KQED question and the comments are filled with +Andrew Dressel 's and Calvin Hulburt's back and forth about bicycle dynamics. Calvin calls us "Whipplites" after the main model we rely on to make predictions about bicycle and motorcycle dynamics. Andrew was quite persistent with this guy. He's also posted on his blog:

badbicyclescience.com

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Very nice article that gives the history of and influence of Jim Papadopoulos's bicycle research. The even mention Mont and me, although getting a few things quite wrong. For example, this quote about my research results: "The research confirmed the long-standing assumption that more stable bikes handle better, and potentially gives frame builders a tool to optimize their designs." which is completely untrue. No one has determined a link between stability and handling yet. They also more or less attribute Luke's robot bike to me, which is not correct. But otherwise, quite a fun article to read. I didn't know a number of the things about Jim's life.

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Someone has information what is going on wit lit-motors?

http://litmotors.com/

If I had money I would buy one of these and sell my car!

But it's not clear when they will start production, no information from the website since June 2015...

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It is always tempting to ask frame builders or racers to try to explain how geometry affects handling. But this is wrought with problems because human perception is too large a variable to get reliable answers from. For example a frame builder is quoted as saying:

‘All bicycles are more stable the faster they move but more trail makes it easier to stay upright. On the downside, more trail means more wobble when you’re out of the saddle and it requires more effort from the rider to steer when it comes to cornering.’

These kinds of anecdotal statements based on experience and perception are often easily debunked with a counter example. This paper:

http://science.sciencemag.org/content/332/6027/339

is a perfect example of this. The big takeaway from that paper is that you can drastically change the dynamics of a bicycle by altering any one of the 20+ parameters. It is highly probable that a bicycle can be made that "takes more effort to steer in cornering" which has less trail than a bicycle which takes less effort to debunk one of the above claims.

The other thing to keep in mind about these anecdotes, such as:

"Framebuilders cite bottom bracket height and wheelbase as the next two most influential geometrical elements for handling."

Are that a frame builder's definition of what a bicycle is is extremely narrow. Most standard diamond frame bicycles vary little in geometry and thus vary little in dynamics and handling.

Articles like these have appeared many times over the years and are generally not worth reading, as all they do is add to the confusion. At least this article ends with:

"What is apparent is that there’s no simple solution to predicting a bike’s handling."

One last note. Jim Papadopoulos once told me a story about a new mountain bike design which had no top tube (just an x-like frame). The professional riders that tested it didn't like it and called "squirely", "nervous", "flexible". The bicycle was then taken behind a screen and a non-structural top tube was attached to change the visual appearance. The bicycle was brought to the same testers without them knowing that it was the same bike. All-of-a-sudden, the testers loved the bicycle and a whole new set of vocabulary was used to describe it's performance.

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TU Delft is hiring a PhD level student to work on singe track vehicle dynamics and control. See the linked PDF for more info.

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Quote from Andy Ruina:

he hopes to unveil an "unusually robust robotic bicycle" in the coming months

I wonder what they are up too.

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This bike has suspension that changes properties depending on the configuration of the motorcycle (namely roll angle).
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