Dynamic Stability of Bicycle Design

What's an "electro-optician"?

Perhaps, someone who looks at electricians or someone who stimulates optic nerves with electricity.

For lack of a better word, its someone who practices electro-optics. Not too hard was it? :)

Back to the subject.I am trying to define since a long time ago,without succes,"control".Let's say differents cranes do the same, one is a boom with a wire from top to some hook,the other one is ridgid segments to the hook,etc.may be one is faster, may be the other one is more precise movements etc.but what the crane operator needs is control? maneu--(that)--bility? or what exactly?if so clear what not coefficients for each machine type and end the discussios among cranes operator which loves those types they use?

I'm not an expert with trucks and cranes, but I would think that in lifting heavy loads, you want the entire package to be stable. You want to limit end effector of boom from oscillations and the outliers from dangerous swaying motions. Growth of such motions may cause loss to life or property, especially in heavy equipment. Maneuverability is just what you described - being able to make a controlled series of movements to move, grab or pick or place a target somewhere. Not sure how it is in crane circles, but I can imagine one model being better at maneuverability in tighter spaces than another because of the way the linkages are made (just throwing it out there). You probably have to pay a larger sum of money for such privileges, I take it. :) Hope this sort of answers your query.

I quite agree with the design being very complex, having built a recumbent I found that the number of important variables is significant.

Wheel diameter, tyre width, trail, steering angle all are aspects that need consideration. In my case I had an articulated steering column with an automotive steering hooke joint. When these things run at an angle the other end does not revolve the same number of degrees as the handle end. Boy, did it make a difference turning it 90 degrees - it went from unrideable (like one of those bikes fitted with reversed steering) to rideable with concentration, this became second nature after a while.

Great to hear from someone who's tried it. Considerable experimentation is going with bicycles at Delft to study its motion and quantify the many parameters that positively and negatively affect design. You're also welcome to read my blog (link in original article) as I keep track of such events and try to break down the really complex science involved for readers and cycling enthusiasts.

There was an article on this in "Scientific American" a long time ago. One of the keys is that the steering forks bend (or offset) so that the steering wheel axle is forward from the axis of the steering post.

The offset is called rake and is one of the many factors affecting bicycle design. Rake alone doesn't tell you completely what manner a bicycle should behave at various speed ranges.