Subject: Re: FRAME DATA Posted by: Nelson Ferreira Tobias, Mechanical Engineer ( University of Brasilia, BRAZIL ) on December 22, 1999 at 05:53:45: In Reply to: FRAME DATA posted by PATRICK KWAN on December 19, 1999 at 04:55:37:

Message: >I actually doing an experiment on vibration analysis on bicycle frame, it >is about to measure the natural frequencies, vibration mode shapes and other >characteristics, then applying damages on the frame and then do such >experiments again to find another set of nat. freq. and mode shape, then use >these data to compare with the theoretical assumption. > I will connect the exciter and force transducer and accelerometer to the >frame, and then through the spectrum analyser to analysis the vibration mode. > By making such assumption, i must have to know the dynamics of the >bicycle frame, stiffness, load distribution when external force is applied. > Therefore i want to search informations about the mechanism of bicycle >frame, and force dynamics and other data required to make my assumptions. > Again thank you for your kindness! >Patrick Kwan Mr. Kwan, I´m very interested in this subject and now i´m designing a mountain bike frame.I don´t have a defined geometry yet, but i´m doing some simulations using ANSYS 5.4.This software works with static and dynamic analysis and i think it can help you.I didn´t study bicycle´s dynamic behavior yet, but i will really like if you can send me a case to study here in my laboratory, because i don´t know if you have acess to the above mentioned software. You can try to use ALGOR and they have a demonstration to send you free for a test period in their page ( www.algor.com ).I would like to know if you have a kind of manual or rules to stabilish bicycle´s geometry or tips about this subject. Thank you very much for your attention in read this e-mail Ass. : Nelson Ferreira Tobias, Mechanical Engineer ( UnB )