I Static analysis of bicycle frame - Need some clarification

AI Thread Summary
The discussion centers on analyzing the static forces on a bicycle frame during a vertical fall, using the energy principle to calculate force based on mass and height. The main challenge identified is the unknown variable of suspension travel, which affects the analysis. The user expresses confusion about incorporating the damping effect of the suspension into their calculations. There is also a suggestion to clarify the problem and present the work done to facilitate better assistance. The conversation highlights the importance of clear communication in technical discussions.
DanielSu
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Hey,
I am interesting in analyzing a bicycle's frame statically from a vertical fall of x metres, this after using the energy principle i get that the force F = mv^2/r, where v = sqrt(2*g*h), r is the deformation of the bicycle at its contact point and m is total mass from the cycle and cyclist. The only unknown i have is r, which i assume to be the suspension travel (there is one at the front and one in the rear) and i use the linkage to get the correct travel at the contact point.

The issue i find is that when i use this formula i do not consider the "damping" effect that the suspension has during its travel, i can of course do some backwards-engineering and use the knowledge of my spring constant and calculate at what height will the suspension reach the bottom but even then will i not take in consideration at how the suspension has dampened the fall.

My first idea was to simply subtract forces and use the abundant force from maxing out the suspension and use this in my static analysis, however it seems like i confuse forces with energy by doing this.

For my analysis i use Ansys btw.

Kind regards,
Daniel
 
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Hi DanielSu. Welcome to PF!

Your question, I am afraid, is incomprehensible. If you wish others to help you with a problem you have to state the problem clearly. You also have to actually show us what you have done to solve the problem.

AM
 
You're right Andrew, i will delete this thread and repost a new (better) one If i find the time, i think by just writing this thread i made stuff clear in my own head (and things unclear in yours).
 
There is no shame in asking for help! If writing this the way you have makes you think you have made it clear in your mind, that should be a bit of a red flag. Feel free to ask for help - you would be surprised how kind and helpful PF can be!
AM
 
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