Susprog - Motion Ratio

[Horace]

Hello,

I've been designing the rockers with Susprog and have learned the software enough to get me the motion ratio throughout the shock travel. However, susprog automatically makes the motion to be linear by default. Is there anyway to change that for it to calculate the rocker points?

Thanks,
Horace

[Mike Cook]

I am not familiar with the software, but, if the motion ratio is linear, the software is not accurately calculating your wheel rate, or it is only calculating it for one height - either way is wrong. I think you might have more luck and fun writing a simple matlab program to explore your wheel rates.

[JHarshbarger]

I'm having a hard time understanding exactly what you're saying. Are you saying that Susprog automatically positions the rocker to be in plane with the pushrod and the shock? If you want to change the angle of the rocker, you can deselect "calculate axis point" or something like that in the bellcrank window, and you can then specify where you want the axis point to be. Was that what you were asking about? If not, post screen shots of what you are referring to.

I think Susprog is a great program and it has saved us a heap of time over the last couple years. There will be things that Susprog is limited to, but for basic geometry design, it's great.

[HenningO]

From what I can remember from my very limited Susprog experience is that you can see how the motion ratio changes over say bump in the data printout. It'll look something like this:

Travel MR
-1 0.83
-0.5 0.85
0 0.92
0.5 0.97
1 1.02

You can also set how big the increments should be between each calculation point.