Request: Linear Potentiometer Damper Data

[T. Neff]

First off, let me say that this is my first post, however I'm not new to the forum or FSAE. After searching the boards, I have come up with nothing (not to my surprise, as I don't see any reason to post this type of stuff).

I am hoping that there are a few teams out there that have damper data saved from past testing and competitions. Would anyone be willing to give our team some data, ANY data, from one or more laps around an autox course.? This would help us out more than I can say. We currently don't have the budget for a data acquisition system, and also haven't in our previous years. This year, we are trying to design the suspension with some emphasis on real world data, rather than what we have done in the past.

If anyone, or any team, is willing to help us with this, we would be extremely grateful.

Thanks in advance!!

Tyler Neff

[exFSAE]

What good would it be?

You want to use this 'real world data', but to what end? What do you want to get out of it exactly?

IMO damper pot data by itself is gonna be worthless. Going to be completely dependent on the springs, rocker geometry, damper settings, all that good stuff. No chance of determining loads or anything like that without detailed knowledge of the above.

Even if you got wheel forces for a team, that in itself may be of little value. If your car's weight or CG height far exceed that of the data donor, YOUR loads when the car is running will be dramatically different.

What would POTENTIALLY worth looking at, or at least much moreso than damper displacements, would be speed and lat/long G traces, steering, maybe engine RPM, throttle position, etc.

Figure out what kinda gearing you'll need (roughly), the general track layout, max steering lock you need, rough ideas for corner loads for your own vehicle under those G traces.. that kinda stuff.

[T. Neff]

To tell you the truth, I was going to see if anyone had any data at all, and then see if they had speed, lateral accel, ect. The best case for data would even have vehicle path traces, by gps or similar. However anything can help us, and I can massage damper position data to more or less create a virtual course for simulation use.

I'm just hoping there are some teams that want to help other teams out. I hope you guys see FSAE as a community, where the more we help each other, the better the competitions can be.

[Adambomb]

I'm with exFSAE on this, I have a really hard time you will be able to get much of anything useful from someone else's data, unless you also know EVERYTHING about their car from roll center heights and camber curves to damping, spring rate, ARB, etc...and then only if you intend on modifying their overall design for your own use.

As for making a track map from damper data, what type of voodoo data massaging do you plan to use to get that? I've been doing this for several years now and I've never heard of that; in fact, I have a really hard time believing that is remotely possible. Perhaps if you had acceleration data you might be able to do some calc on it, but even that would likely be messy unless you had darned good data.

If you're just looking to get a track map, there are a few of those posted, also if you look up Texas Autocross there is a nice scale map of the '98 endurance course, which is actually not terribly different than what you're likely to encounter these days at competition.

[screwdriver]

I kind of understand where you're coming from. If you want to create a virtual road to test your suspension on, going from measured spring deflections gets you close to nowhere. You will have to calcualte backwards through the tyre which is close to impossible.
Try looking at the "spectral density of bumps" (1) in the literature.
This book has a nice section on it:
http://www.amazon.com/Dynamik-...d=1256075327&sr=8-17 (http://www.amazon.com/Dynamik-Kraftfahrzeuge-VDI-Buch-Manfred-Mitschke/dp/3540420118/ref=sr_1_17/182-5147800-4307812?ie=UTF8&s=books&qid=1256075327&sr=8-17)
You will find what you are looking for in the band B of the book on Page 27ff.
I've applied this sucessfully in the past to generate realistic road noise profiles.

(1) I've exhausted my technical English here - it's called "spektrale Unebenheitsdichte" in German

[Scott Borg]

I've shared data with others in the past, sorry it didn't contain damper position. Original thread here if you'd like to post your email.

http://fsae.com/eve/forums/a/t...07348/m/98010053/p/1 (http://fsae.com/eve/forums/a/tpc/f/125607348/m/98010053/p/1)


If I forget to check these boards for a while, you might try contacting others who received datalogs.