tag:blogger.com,1999:blog-13887692.post8001383539518425878..comments2024-03-13T02:16:08.135-04:00Comments on Cozy Beehive: Dynamic Stability Of Bicycle Design : Part 4Ron Georgehttp://www.blogger.com/profile/18394865788996482667noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-13887692.post-67861344192368996542009-09-25T00:13:12.856-04:002009-09-25T00:13:12.856-04:00Thanks Jason. Paterek is likely talking about bike...Thanks Jason. Paterek is likely talking about bike handling I agree. And with respect to stability in systems, I can think of one good application where stability would be prime. Let's think of the robot designed to study and take measurements on a planet. It'll land on the planet with the help of a parachute and some distance before it lands, the chute deactivates. The robot's airbags will cushion the landing. Now the chute must be stable enough to limit oscillations of the robot while descending. Too much of an oscillation angle will increase the motion of the robot in descent. If this is not controlled, the airbags of the robot could puncture when they hit the surface. Mission failed! :)Ron Georgehttps://www.blogger.com/profile/18394865788996482667noreply@blogger.comtag:blogger.com,1999:blog-13887692.post-78176016908756110032009-09-24T21:11:11.598-04:002009-09-24T21:11:11.598-04:00Paterek is talking about bike handling, where as o...Paterek is talking about bike handling, where as our studies are about bike stability. There are generally some types of relationships between stability and handling. I would claim that most of the time stability does not equal good handling but that isn't necessarily true. Fighter jets, race cars and other highly maneuverable vehicles tend to be designed such that they are either unstable or on the verge of stability. The key is to find that relationship and it is super tough because the human is in the loop and handling is very subjective.Jason Moorehttps://www.blogger.com/profile/15362357639624306439noreply@blogger.comtag:blogger.com,1999:blog-13887692.post-47663369472736455972009-09-24T17:51:04.587-04:002009-09-24T17:51:04.587-04:00I think we probably agree then. I was just under ...I think we probably agree then. I was just under the impression that you were treating Paterek's claim as though it were talking about exactly the same thing as Jason et al and coming up with different values.<br /><br />That was a fantastic series - and a great blog as a whole. (I should have said this in the first comment.)Trisnoreply@blogger.comtag:blogger.com,1999:blog-13887692.post-70388975091708647652009-09-23T10:22:56.769-04:002009-09-23T10:22:56.769-04:00Tris : Stability and the modes of bicycle motion, ...Tris : Stability and the modes of bicycle motion, as we talked about in Part 3, is a steering phenomenon too. One of the most talked about parameters associated with steering stability is trail. Without positive trail, there's no caster phenomenon.<br /> <br />Paterek could be right from experience and principles. On the other hand, Jason et. al studied the bicycle TEHY HAD (that's important) for its parameters and found no correlation between Paterek's statement on the prescribed range for trail and what they found in their study, as you can see from the graphs on trail vs stability range. <br /><br />In hindsight, too much stability is certainly bad for a bike and Paterek maybe right, but his definition of a "comfort" zone is ambiguious. But he does not have a scientific definition of what he means by comfort so its pretty ambiguous and open to interpretation. Certainly, comfort is better with a more stable bike and if that's the case, then a higher stable speed range with trail means more comfort in straight line motion right? Atleast this is what I feel. You can disagree with me.Unknownhttps://www.blogger.com/profile/12256394060474969622noreply@blogger.comtag:blogger.com,1999:blog-13887692.post-19290655553696967862009-09-23T08:31:07.109-04:002009-09-23T08:31:07.109-04:00I may be wrong here, but I'm not sure it's...I may be wrong here, but I'm not sure it's fair to say that any of the findings contradict what Paterek said.<br /><br />I think that most likely Paterek is not talking about a bike's self-stability, but rather how well the bike handles for an experienced rider. Surely the two are not the same.<br /><br />(FWIW, I'm not convinced that Paterek's range of trail is correct for all bikes, but I don't think that the findings about self-stability have the direct relevance to his claim as this post seems to suggest.)Trisnoreply@blogger.comtag:blogger.com,1999:blog-13887692.post-49911423702740102782009-09-22T23:16:47.557-04:002009-09-22T23:16:47.557-04:00Thanks. I just corrected that.Thanks. I just corrected that.Ron Georgehttps://www.blogger.com/profile/18394865788996482667noreply@blogger.comtag:blogger.com,1999:blog-13887692.post-81768200611340525492009-09-22T14:30:38.691-04:002009-09-22T14:30:38.691-04:00There doesn't seem to be a link to an enlarged...There doesn't seem to be a link to an enlarged image for the last page.Gary Younghttps://www.blogger.com/profile/07932832538448170566noreply@blogger.com