Motion Ratio of Spring/Shock in 3d Analysis

[shoulddt]

Hello everyone, I am trying to calculate the motion ratio of a shock/spring (coil-over) in a double wishbone front suspension design. There are many tools and equations for 2d analysis, however I am working in three dimensions. I am needing the equation to derive the motion ratio for a program I am developing. I have a 3d front suspension program I am using to validate my code, but I cannot get the same values they have for motion ratio.

Does anyone know how to calculate the 3d motion ratio? I can provide sample dimensions and values, however it would be hard to make sense of.

 

[GregLocock]

work out the length of the component L0 at a given ride height H0. Repeat a a new ride height H1, to give new length L1

MR=(L1-L0)/(H1-H0)

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[dynatune4xl]

Or use a 3D vector algebra based suspension analysis tool. They are available. Even in Excel.

Cheers,
dynatune

 

[BUGGAR]

Does your geometry cause a progressive rate giving you a variable motion ratio?

 

[gruntguru]

Fixed motion ratio would be the exception rather than the rule.

An empirical method (plot spring deflection vs wheel deflection across several points) is the usual way. Then fit a function if required.

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