FSAE Tire Test Consortium -- Round 3 [Archive]

Edward M. Kasprzak

06-13-2007, 08:28 AM

Hi all,

I've been watching the thread, and here are some answers to your questions:

1. How were tires selected? We're testing tires that are either new or are older but haven't been tested yet. The only repeat this time is the Hoosier 7.0, which will help compare against the previous tests since the test program has been revised.

2. Newbies? Anyone not familiar with the FSAE TTC should follow the link in my initial post (top of thread).

3. What Michelin? We've asked Michelin to supply tires, and they agreed to send us four. We're not sure what compound they're sending--tires should arrive at Calspan in the next few days. We'll know then. We're not testing any rain tires.

4. Rim width idea? We have had this idea in our pocket since the first round of tests. It was axed previously when it landed in the "you can't do everything" category. Previously we focused on putting as many tire constructions as possible through the machine. We hope that the round 3 data will show some general rim width effects that can be translated to tire constructions tested in the previous rounds.

5. Peaks? We try to get to the slip angle peaks, but if the peak is past 12 degrees you're probably not going to see that on the car anyway. One issue is that the surface at Calspan is very clean, unlike the surfaces most FSAE cars run on. We think this causes the peaks to be somewhat high on the test machine. We've had a LOT of discussions about what to do about this--there are many constraints at the test facility that limit our options. In round 3 we're using a different belt surface that we think will help this issue--another reason to re-run the Hoosier 7.0 as a "control" tire to compare against the data from the first two rounds.

We appreciate all the interest, comments and questions, not to mention the encouragement. Myself, Dr. Bob Woods and Doug Milliken put a fair amount of volunteer time into the project and it's nice to know it's appreciated. In the last week the 100th FSAE team paid their membership fee! We'll keep trying our best.

Let's hope for a good, uneventful test next week.

Edward M. Kasprzak

06-14-2007, 09:57 AM

Hi all,

The schedule at Calspan has changed, owing to one of their major customers needing the time on the tire testing machine next week for a high priority project. We're tenatively rescheduled for June 28-29. I'll post again when I know more certain information.

Mike Cook

06-18-2007, 11:17 AM

I hear hoosier is coming out with a new tire very soon. May want to wait to test that tire as well.

Mike

ben

06-20-2007, 04:29 AM

Edward makes some very good points as to why obsessing about the peak on a flat trac test is possibly not worth the effort.

As a design judge what I'd like to see is someone clearly stating and accepting that the grip level on the flat-trac isn't the same as that on the track, using the flat trac to determine a model of the carcass (which is what it actually does best) and adapting this carcass model based on actual friction coefficients determind from a separate model or track test.

Bearing that in mind, the rim width test would be the priority for me because it will have the biggest effect on cornering stiffness and therefore vehicle balance.

The peak slip angle is simply a function of the torsional and lateral carcass stiffness and the grip level. Use the flat trac to determine the first two and accept that it may grossly overestimate the last one.

Ben

Paul Garcia

06-20-2007, 10:36 PM

Ed,

Could you discuss the difference in peak friction coefficients from the test results to what we see on the track. Are there measures you are taking in this third round of testing to account for this or is it just the "way it is?" Any plots of normalized lateral force show the test results do not reflect the true grip capability of the tire. The data shows peak friction coefficients higher than 2.5.

I apologize if you've explained this before.I am sure you have at least heard the question as I raised this to Doug Milliken previously and he was familiar with the topic. His suggestion was to use road coefficients lower than 1, say 0.7, to attain more "useful" data. Judges this year were very interested in discussing this very topic.

Does this seem like a reasonable method of scaling the data?

Would the "line of peak" slip angles be changed significantly in a way that this method may not reflect?

Paul Garcia
Jayhawk Motorsports

Jersey Tom

06-21-2007, 07:48 AM

One issue is that the surface at Calspan is very clean, unlike the surfaces most FSAE cars run on. We think this causes the peaks to be somewhat high on the test machine. We've had a LOT of discussions about what to do about this--there are many constraints at the test facility that limit our options. In round 3 we're using a different belt surface that we think will help this issue--another reason to re-run the Hoosier 7.0 as a "control" tire to compare against the data from the first two rounds.

Paul - is this what you're talking about? Sounds like theyre going to try to alleviate the issue a bit.

Scaling the road coefficient down.. I wondere if that just scales down the overall coefficients of friction, and doesn't really change the shape (thus not making any peaks stand out).

Edward M. Kasprzak

06-21-2007, 11:56 AM

Thanks for your comments Ben. I generally agree with you, and if you're trying to build a model of the tire carcass then I completely agree. Since most students are not, however, I'd like to take Paul's request and comment a bit on the relationship between the peaks in the data and the peaks on the track. The data at the peaks is more applicable than Ben may have indicated.

Let's start with the obvious: the surface on the test machine at Calspan is not the same as the surfaces that FSAE cars drive on. Of particular concern to us is how clean the test facility surface is and how much dirtier real surfaces are. FSAE cars tend to run in parking lots which are often very dirty, and even at the Detroit event (Ford proving ground) the outdoor surface in the vehicle dynamics area gets dusty and rained on, etc. The surface would "come in" if enough cars did enough laps to work in a groove, but this might only start to happen toward the end of the endurance event.

Thus the real surfaces have less grip than the Calspan test machine. To close the gap we're running Round 3 on a test surface at Calspan that we think will have less grip, although the Calspan test data will probably still show higher grip levels.

So is the data junk? Absolutely not! Rather, this is an issue that has been around for as long as there's been laboratory tire testing. And even if you managed to get good tire data recorded from on-track driving the surface changes with temperature, amount of rubber put down, clouds/sun, etc., so even then you'd be faced with the same issue. This is where modeling of the tire data begins to play a big role.

What you would like is for the peaks in the tire data to have the same magnitude as the peaks the tire gives on the car when it's operating on your particular surface. Thus, some scaling of the data is required. By far the easiest (and incorrect) way to do this is to take all the lateral force data and reduce it by some ratio so the height of the peaks match. The problem with this approach is two-fold. First, while the height of the peak may now match your on-track experience the slip angle at which it occurs has not been altered from the test data--this is not consistent with what really happens. Lower grip surfaces tend to make peaks at lower slip angles (think of it roughly as not having enough grip to twist the footprint of the tire around an axis normal to the ground). Second, by simply ratio-ing the lateral force down you have also changed all the cornering stiffness slopes. These slopes are, in reality, largely independent of the surface the tire operates on.

Allow me to put my Milliken Research hat on for a minute (I've worked there since '96) and talk about the MRA Nondimensional Tire Model. This model is included on the DVDs and is generally described by Chapter 14 of the Milliken's "Race Car Vehicle Dynamics". The Nondimensional scheme models tires on a more fundamental level than just trying to match the measured curve shape. One of the parameters that is modeled is the friction coefficient, defined as the peak of the lateral force curve divided by the normal load. This value can be multiplied by a surface friction value to scale the data up or down. If scaled down, the resulting tire data has the same cornering stiffness as the original data but lower peaks occuring at new (lower) peak slip angles. This is representative of how real tires behave. Done this way, the Calspan surface friction coefficient is defined as "1.0" and your surface may be "0.7" or something like that. If you try this with the FSAE TTC data you may find peaks occuring for reduced surface friction coefficients on curves where the raw data doesn't show a peak on the test machine.

MRA customers who use the Nondimensional model use this surface friction modifier to match the tire data to their surface (although it's always tricky to get it really close). This value is an input to the model supplied on the DVDs. While tuning this parameter requires a vehicle simulation, FSAE teams can do a reasonably good job by running your car on a skidpad and doing a simple four-wheel model (with load transfer, roll stiffness distribution, etc. to get the wheel loads right) and then adjust the surface friciton coefficient to match lap time. It won't be exact but it will be close (and you'll learn a lot in the process).

Now I'll take my MRA hat off and put my FSAE TTC co-director's hat back on....

I'm not sure how the Stackpole Engineering Services model handles surface friction coefficient variations. We may want to ask SES about that.

As far as Calspan goes, the surface we used in Rounds 1 and 2 is their standard surface. For most tires (passenger and racing) it does a very good job of replicating the grip levels on a normal road or track. It will always be a bit different, but it's usually close. Apparently the FSAE tires are so much softer and liked the clean surface a lot more than most other tires they've tested. Thus, the larger than expected mismatch, and thus the attempt in Round 3 to use a lower-grip surface.

This is a good thread with good questions and comments. One of the FSAE TTC goals is to expose students to tire testing--warts and all. You're identifying good issues and asking good questions. We threw everyone in on the deep end when this consortium was founded in the hopes that discussions like this would develop. Keep thinking and asking questions!

Edward

Paul Garcia

06-21-2007, 03:07 PM

That was a great answer Edward, thanks so much for all the help.

For what its worth...an interesting point I learned while in Detroit was how load variation would effect all of these calculations. In calculating theoretical steer angles (so ackermann) and lateral force potential of the car we did typical load calculations that resulted in 50 lbs (or even less) on an unladen tire.

The comment on this load variation was that actual track performance may see variation in load as high as 50 lbs meaning that trying to interpret optimum slip angles and lateral force for that tire may not be very useful. I would imagine that in his applications (RCR = Nascar) this was true but our much lighter cars see less load variation?

We spent a great deal of time comparing the "line of peaks" to determine steering geometry (which is why we ended up just making it highly adjustable); the drivers said they prefered ackermann while the tire data along tends to indicate the reverse. The steering geometry is best left for another discussion but what did seem important was that good curve fits (like the MRA tire model) remove ALOT of scatter in slip angle and load maybe making this data very "theoretical" at best.

Just throwin those comments out there. You can keep um' or send um' right back...

Paul
Jayhawk Motorsports

Jersey Tom

06-21-2007, 08:11 PM

There's been some looonng discussions on Ackermann, not too far back. Think the big thing was.. the data can indicate that a heavily laden tire likes being at higher slip angle.. but since the force vectors are no longer perpendicular to the direction of the car and you dont know where they are exactl you cant really draw any conclusions beforehand.

ben

06-25-2007, 01:48 AM

Edward - great reply.

I wasn't suggesting that the team's would want to do a carcass model. Obviously having a peak on the flat-trac data and using the MRA tyre model would be the most convinient.

My point as a judge was that the current data doesn't have these peaks and not all the tyres will be retested. This gives the students two options:

1. Believe the data and appear puzzled that you're not achieving the artificially high friction levels on track.

2. Approximate the lateral and torsional carcass stiffness from the data and measure a friction coefficient on track. Use a stretched string model to approximate the true cornering stiffness and then modify the coefficients of the Pacejka model to fit your estimates, then use this tyre model in your simulations.

Of course just being given the peaks from the test would be easier and nice to have. But the student that does what I've suggested above would learn more about tyres and score more design points.

Ben

Edward M. Kasprzak

06-25-2007, 06:02 AM

Ben,

Ah, got it. I now see what you meant. Thanks for your input!

Edward

Edward M. Kasprzak

06-25-2007, 06:08 AM

Hi all,

The tenative test date of June 28-29 at Calspan is not going to happen. Instead, we are scheduled for August 2-3. This time they bumped someone out of that timeslot for us and Calspan assures me the new date will stick. Considering Calspan is already booked through October (two shifts per day) I guess this isn't too bad. I'm not happy about it, but that's the reality of it.

Edward

Edward M. Kasprzak

07-27-2007, 11:26 AM

Hi all,

I spoke with the crew at Calspan earlier today. Right now all systems are go for testing on August 2-3. All tires are in, all wheels are in, we are *extremely* unlikely to get bumped this time, and (except for the ever-possible mechanical issues at Calspan) we fully expect to commence testing on Thursday.

If you wish to attend, please e-mail me once again and I'll give you detailed instructions. I know of members from at least four teams that are interested in watching the testing. I'd suggest visiting on Friday instead of Thursday, since a good part of Thursday may be spent preparing the machine for our tests (which is only slightly more interesting than watching paint dry).

I'll keep you posted on the progress of the tests. Again, we expect the data to be shipped in mid-to-late August.

Edward

Edward M. Kasprzak

07-30-2007, 08:15 AM

Hi all,

Calspan is now ahead of schedule. Set-up and machine preparation is now scheduled for Wednesday, with a full day of testing on Thursday and on Friday we'll do whatever's left.

So, the best day to visit the tests is now Thursday. Again, let me know if you plan to attend.

Edward

Edward M. Kasprzak

08-02-2007, 03:59 AM

Testing started yesterday afternoon (8/1) and will continue today and into tomorrow. So far so good. Calspan has solved the load control problem they had in the first two tests--a major improvement.

Edward

rkellz007

08-07-2007, 09:22 PM

Edward,

Which tire did Michelin submit?

Edward M. Kasprzak

08-09-2007, 09:20 AM

Testing at Calspan concluded late last week. Everything went rather smoothly. I will have the data from Calspan by tomorrow, and then it will take us two to three weeks to obtain models from SES & MRA, compile the DVDs and ship them to consortium members.

If you want to check that I have a functional shipping address for your school please e-mail me directly. Note that we prefer on-campus addresses over private residences.

Someone asked what tire Michelin submitted. It's their 16/53-13 Radial X. According to the sidewall the compound appears to be BL245, although I have not been able to find this as a listed compound on any of the Michelin websites. I'm waiting on confirmation from Michelin that I've read the right code. None of the compound codes listed on their website appear on the tire (unless I'm missing something).

I'll let you know when DVDs are shipping. We're trying to get them out by Sept. 1.

Edward

RacingManiac

08-09-2007, 03:13 PM

have the Goodyears been retested on the correct orientation for corneing>? And have Goodyear made their choice as to which data are they releasing to us?

Andrew (or Frank...lol)

Edward M. Kasprzak

08-10-2007, 05:26 AM

The Michelins tested are simply the "B" compound.

Edward M. Kasprzak

08-10-2007, 05:33 AM

Andrew,

Yes, the Goodyears were tested in both orientations. We hope to release all the data.

For those who weren't at the test, here's the story: The new Goodyear is an asymmetric tire, with painted lettering on one side and the words "mount this side in" molded into the sidewall (small letters) on the other side. Nobody caught this instruction at first, so the inclination angles were initially run the "wrong way" (top out instead of in) for the construction. The tests were later performed with the inclination angle in the correct direction.

The data sent on DVD will contain a note to this effect.

I'm suggesting that Goodyear put the words "mount this side out" on the other side of the tire and make the lettering a bit bigger.

flavorPacket

08-10-2007, 06:50 AM

well, at least now we can all look and see how much Goodyear have biased their sidewalls to help with orientation

rkellz007

08-10-2007, 07:33 AM

As I understand the assymetry it is not a sidewall construction issue, but instead something in how the contact patch is molded.

RichE

08-16-2007, 08:09 AM

I'm not sure how the Stackpole Engineering Services model handles surface friction coefficient variations. We may want to ask SES about that.

Hi Edward,

The Stackpole Engineering model gives coefficents for a Pacejka 96 Magic Formula tyre model. In this model it is possible to use several user scaling coefficents to manipulate the data, one of which is a peak friction coefficent. Adjusting this value effects the tyre data in much the same way as you describe for the MRA model.

hope this helps people to use the data.

On another note, I wanted to try and evaluate the transient properties of the tyres, in particular the relaxation length. I am trying to model in more detail turn in and other transient events where the lateral force lags behind the slip angle.

I have noticed from one of the files on the dvd from calspan, "TIRF-SA_procedure" that the SA data is not actually the raw measured data and that it is passed through a program to remove the very hysteresis I was interested in measuring. Do you know if it is possible to get a copy of the raw data or has this now been deleted?

thank you
Richard
Cardiff University

Edward M. Kasprzak

08-17-2007, 03:56 AM

Richard,

Thanks for the feedback on the SES model. As for the SA procedure, I looked back at the cover letter in the "fromCalspan" folder. It turns-out that the SA procedure is only applied to the raw data in the Mixed units folder (which SES uses).

The raw data in the Metric and USCS folders are untouched, so they have the (small amount of) hysteresis you're looking for. We swept slip angle at 4 deg/sec in the test to avoid a lot of hysteresis due to slip angle transients. The data is meant to be approximately steady-state. This is somewhat unfortunate for your purposes, but transient testing is yet another discipline we could investigate in a future test.

That said, there should be transients apparent in the warm-up and at the start of each slip angle sweep where the sweep rate is much higher. This data, however, is not provided by Calspan's data reporting routine (plot slip angle vs. elapsed time to see the gaps in the data). I'm working on the Round 3 data now, so I'll ask Calspan if they have the "full" data sets kicking around, or if they only collected data at the times we see in the files. If they have the "full" data I'll get it on the Round 3 DVD.

Edward

RichE

08-17-2007, 05:23 AM

Hi Edward,

Thankyou for looking into this for me. I would be very interested to see the warm up and conditioning data if it is available.

Many thanks
Richard
Cardiff University

flavorPacket

08-19-2007, 02:49 PM

I'd like to echo Rich's request. The way a tire is run-in on the flat trac made a huge difference in data during my team's force and moment testing

Ulf

08-27-2007, 09:13 AM

Hi Edward,

any update with regard to the evaluation of the test data? Are the DVDs still likely to be sent out by next week?
Can't wait to have the new data...

Cheers, Ulf.

Edward M. Kasprzak

08-29-2007, 10:07 AM

Yes, next week is still the target for shipping the DVDs.

Edward

duckei

09-04-2007, 09:38 AM

I and other members of our team want to join the tire test consortium. It seems like a good investment as we are running Hoosier's and we don't have exact tire data. Have any of you been successful using this data? Is it worth the price?

Thanks

-Ian

Hyder

09-04-2007, 11:38 AM

Hi everbody i am new to this forum, joined recently.
Can anyone help me, I need to know what are the forces which will develop in the machine frame and their formulas.

I am designing a static tyre testing machine which should capable of measuring lateral, longitudinal,vertical and cornoring stiffness, can any one help me to comeplete my project.

waiting for the response.

Hyder

09-04-2007, 11:58 AM

Hi everyone
please help

I am doing a project work in " designing a static tyre testing machine" which can test for lateral, longitudinal, vertical and cornering stiffness.

can anybody reply me what are the forces developed in the machine frame (shear force, bending moment etc and their example calculations if possible)

or can anyone suggest me a link or a report which contains material selection and its evidence and general force calculation.

In order to get masters I need to complete my project, please please please can anyone reply me.

I will be very grateful if I get a reply.

waiting for the response

thanks in advance

Anday

09-04-2007, 01:12 PM

This may not be the best thread to ask this question. Those of us who are members of the Tire Test Consortium paid for this data that we could not get ourselves. I would think Cal-Span would consider this propietary information.

But to help you out, if you can figure out the loading at the contact patch, some Free Body Diagrams will tell you the loads into the frame you design.
I would hope that you want this information to be sure your rig is stiff enough to not affect your data. If you have any flexure it will throw off your data considerably. The rig should be significantly "overbuilt" for stiffness.

You could also try sae.org, there is a paper about the Tire Testing at Cal-Span. That may or may not help you at all. Also search the forums, it is the fastest way to find what has been discussed before.

Maverik

09-06-2007, 11:46 AM

Has the data gone out yet?

Edward M. Kasprzak

09-07-2007, 06:04 AM

The data has not been shipped yet. We're waiting on SES and MRA to finish the models of the data. I communicated with Mike Stackpole at SES and he says he should have it done later today or early Monday. Same goes for MRA. Both are in the same boat--paid work caught fire and took priority.

I know everyone's eager for the data. We're doing the best we can. Once the models come in all I need to do is make copies of the DVD (appx. 1 day) and then ship them. The shipping materials are already assembled.

I'll post when the data is shipped.

Thanks for asking,
Edward

Edward M. Kasprzak

09-13-2007, 05:50 AM

Still waiting on SES....

Dan Lentsch

09-24-2007, 01:24 PM

Any news on the projected ship date?

Ulf

09-25-2007, 05:24 AM

Hello Edward,

is it possible to download the new data from a ftp server?
Otherwise it will take quite a while until the dvds reach us and I'd like to shorten taht time as much as possible.

Edward M. Kasprzak

09-26-2007, 05:34 AM

We're still waiting on SES. Everything else is ready to go--shipping labels and DVD labels are printed, customs forms are filled-out (for the international shipments), etc. Once I get the models from SES I will make the master DVD, get it copied (appx. 1 day), assemble the packages (1 day) and ship it. Considering it's already Wednesday the earliest it would ship is the weekend.

I appreciate everyone's patience. I know mine is frayed. I'm doing what I can to move SES along. I know it can be difficult since they're doing this volunteer work on top of their paid obligations, but at the same time it's been about a month now and I really hate to see all the students left hanging.

And to answer the other question, we won't post data on an FTP server. It's not secure enough and too much of a hassle to make it so.

Edward

Edward M. Kasprzak

10-01-2007, 04:53 AM

SES came through, so I'm finishing the DVD, will have copies made and will have them shipped by the end of the week. I'll post when they've been shipped.

Edward M. Kasprzak

10-06-2007, 11:06 AM

Good news. The Round 3 DVDs have been shipped. Look for them at your school sometime in the next week.

Boston

10-10-2007, 06:35 AM

Got mine, thanks!

FryGuy

10-10-2007, 10:29 AM

Does anyone know which rim width the hoosier 20.5x7.0 -13 was tested on in round two? Im trying to compare the two rounds of testing.

Now as far as procedure goes, was the belt "stoned" in all runs or just certain ones?

t21jj

10-11-2007, 07:46 AM

We just received our copy.

Thanks

CU - Andrew

10-12-2007, 05:30 PM

Cedarville just got our copy too - and we're first-time members. Thanks so much for organizing this, and for putting all the work into those Matlab files!

Edward M. Kasprzak

10-13-2007, 06:32 AM

The same belt was used for all Round 3 tests. It was stoned before testing started, so it's the same surface for all the tests.

The Round 1 and 2 tests on the 13" tires used a 7" wide rim. Note that those rims were not used in the Round 3 tests. The Round 3 rims are steel and were purchased by the FSAE TTC so that all rim widths would have the same rim construction. The Round 1 and 2 rims were aluminum and were lended to the consortium for the project.

If you don't see your copy of the Round 3 data by sometime next week then drop me a note and we'll check your team's mailing address. The vast majority of you will be okay, but with appx. 130 DVDs shipped it's not unreasonable to think that at least one will have an issue.

MalcolmG

10-17-2007, 10:17 PM

got ours this week, thanks Ed http://fsae.com/groupee_common/emoticons/icon_smile.gif

Jonny_B

10-27-2007, 01:47 PM

Hi all, I'm really interested in buying this tyre data for our team... We're developing a vehicle dynamics model. But has the new testing surface brought the peaks to more sensible levels?

Also am I right in understanding that the non-dimensional model can be used to 'correct' the data from tests 1 & 2 for more realistic lower peak friction values?

Many Thanks,

Jon

Edward M. Kasprzak

10-29-2007, 05:43 AM

Jon,

First, the stoned surface made little difference in the peaks. Second, yes, the nondimensional model allows the surface friction to be adjusted, affecting the shapes of the curves in reasonable ways.

scott_rfr

10-29-2007, 03:45 PM

Dr. Edward M. Kasprzak I sent you an email last week about not receiving our CD yet. Did you ever get it? I never recieved an email back.

Scott Mingay
smingay@rutgers.edu

GooDLuC

11-01-2007, 02:29 PM

Hi,

Does anyone got this error using the ExpansionType 5 with any of round 3 tire data file:

??? Error using ==> rdivide
Matrix dimensions must agree.

Error in ==> U:\TTC_Data\Round3\fromMillikenResearchAssociates\ expand_mrandim.p>expand_mrandim at 792

Error in ==> call_mrandim at 209
MZ = expand_mrandim([5,units],NDIM5,[FZ,SA,IA,0,mu]); % Call to MRA Nondimensional Tire Model

We tried hardly to find the problem but since it occur in the .p file we can't get acces to the code to find which matrix are involved in the rdivide operation.

So please if someone got this error and find the way to get thru or if Dr. Kasprzak could take a look the code and help us to resolve the problem, we would appreciate very much.

Thanks!

Edward M. Kasprzak

11-01-2007, 03:02 PM

Scott,

Yes, I replied to you, but the mailer-daemon couldn't deliver it to your address.

Edward M. Kasprzak

11-01-2007, 03:04 PM

Milliken Research has been contacted regarding problems with the aligning toruqe expansion. We've scheduled it among our current work and hope to have a resolution next week.

simon_o

11-02-2007, 04:23 PM

Hi,

I just started using the tire data from FSAE TTC. I am building a vehicule dynamics model but I am not sure in wich direction is the FY returned by the MRA Nondimensionnal model. Is it always perpendicular to the belt displacement or is it in another direction (perpendicular to the tire) ?

Does anyone can

VinceL

11-02-2007, 07:35 PM

simon_o

The MRA models follows the SAE tire axis system. That means that lateral force is perpendicular to the wheel heading direction and positive to the right. It doesn't matter what the slip angle is or how the tire is distorting. The only thing that matters is the wheel.

simon_o

11-03-2007, 04:03 PM

Ok thank you!

GooDLuC

11-06-2007, 04:06 PM

Is it me or the "camber effect" on lateral and longitudinal loads is reversed for the Goodyear tires?

We plotted a graph showing FY vs SA for a given FZ and various camber. According to SAE tire axis system, negative IA should produce a negative FY @ SA=0 but on the graph we find a positive FY @ SA=0. Also, we can see the tire generate FY load for IA=0 while other tires generate nothing @ IA=0.

On a second graph showing FX vs SA for a given FZ and various camber. The graph shows that the higher the SA, the higher FX is. This don't really have sense.

Am I right? Could someone tell me how to correct this problem. I looked at other tires (round 1, 2 and 3) and "camber effect" seems to be right for those tires.

Have the runs 53, 54 and 55 (with the tire in the backward direction) been included in the tire modeling process? Should we take into account the comment in the DVD content file (reverse sign for SA, IA, FY, ...) when using the MRA model or have this been done already when generating tire model?

Thanks!

FryGuy

11-06-2007, 05:06 PM

I don't think you are allowed to post those on the internet as of tire consortium contract.

GooDLuC

11-06-2007, 05:14 PM

FryGuy, you're right... I forgot about that. I removed the graph. I hope my post will be clear enough without graphs.

FryGuy

11-06-2007, 05:25 PM

I would re-check all your graphs, they didnt exactly look right to me. That tire at certain loads does have some interesting camber effects but it still seems like your graphs didn't quite look right. They could be right but i didn't get a real good look at them before you removed them.

GooDLuC

11-07-2007, 10:02 AM

Hi, I investigated a little further and now I think FX curves for the Goodyear tires have sense.

However, I still can't explain the FY curves behavior.

For exemple: with a 250 lbs vertical load, SA=0 , IA from 0 to 3?) I got:

*0 FY force for IA=0 (which have sense)
*an increasing neg. FY force as IA from 0 to 1 (which is in opposition of what would "normally" happen with other tires)
*an increasing FY force in the pos(+) direction for IA from 1 to +... (which correspond to the expected behavior of a tire).
*For negative IA, the same happen but with sign reversed for FY.

I also plot the same graph with the raw data of run 4 and 54 and what I see is FY going positive as IA increase (expected behavior).

I saw a lot of hysteresis on raw data graph i.e. for IA=4? tests pass trough SA=0 four times and 2 curves indicates a lot of FY+ and the 2 others indicate approximately 0.

I don't know where the error come from but I would appreciate if M. Kasprzak or M. Milliken could take a quick look at the Goodyear tires models vs Raw data and told me why I get these results and may be help me to correct the problem if possible.

Thanks!

VinceL

11-07-2007, 07:13 PM

"I saw a lot of hysteresis on raw data graph i.e. for IA=4? tests pass trough SA=0 four times and 2 curves indicates a lot of FY+ and the 2 others indicate approximately 0."

All of the curves pass through zero four times. That's how the tests are run, watch the test videos. They pass each tire through zero four times in order to get as much data as possible in that area, so they can approximate the cornering stiffness as accurately as possible.

As for the problems with the Goodyear tire I agree with you that its camber response doesn't seem right. MRA is aware of the problems and have scheduled time to fix them.

I hope that helps.

GooDLuC

11-07-2007, 08:33 PM

Hi VinceL,

Thanks for the details.

In fact, for the test, I know how they are run... my point was more about FY value of these curves. There is effectively 4 curves that pass through zero but 2 of these curves give a FY value of about 30 lbs for lateral force while the 2 other curves give a lateral force near to zero (which is what is expected). I wonder what caused this difference.

If MRA is aware of the problem, do you know when we should expect to have some news from them? How do you know the are aware of the problem? Is there any place where the known problems are listed?

Thanks!

Jonny_B

11-08-2007, 05:51 AM

Hi all, I'm developing a vehicle dynamics model of our Formula Student car, using MatLab Simulink (SimMechanics) I would like to incorporate Pacejka's tyre model into this eventually. Does the Tyre Test Consortium data give Pacejka coefficients of the tyres?

Secondly I have a problem; my university wont fund the cost of the FSAE tyre data until I have a model that I can prove will work with pacejka coefficients. So I wonder if anyone has pacejka data for a somewhat 'random' tyre that they would send me? Just to get a working model with Pajecka coefficients that are roughly the right orders of magnitude...

HenningO

11-09-2007, 03:45 AM

Jonny_B, I believe you can find Pacejeka coeffiecients of a tire just using Google. In fact I believe a set of coefs. are given in RCVD. And yes Pacejka coeffiecents are given from the tires, although I personally prefer the MRA Non-dimensional model and if you are writing your own code, I'd use that.

On another note, is there anyone else that would like to see a "closed" forum where schools that have bought the data can discuss it and post plots and figures? Maybe that is something that can be organized in collaboration betweend FSAE.com and Dr. Kasprzak/Dr. Milliken? I mean on this forum we are able to dicuss nearly any aspect of the cars. I don't know about you, but I've learnt quite a lot from these forums, why shouldn't we be able to learn about tires as well?

GooDLuC

11-09-2007, 05:50 AM

Yes, a closed forum would be great. It would be easier to discuss about data if we can post graph.

Edward M. Kasprzak

11-12-2007, 06:36 AM

Hi all,

I owe several people e-mail replies. I've been traveling and am swamped with paid work right now, but I hope to catch-up on my FSAE TTC correspondence in the next week or two.

Jonny_B

11-20-2007, 12:33 AM

OK Can someone tell me about this non-dimensional tire model that is included with tthe tyre data? Is it a 'combined' model such that lateral slip angle will also affect the longitudinal force? I need to write the tire model into MatLab code for my dynamics model - is there any problem with doing this? Also are we provided with mathematical code for the easy generation of tire curves?

We will be purchasing this soon if it does meet our requirements.

Thanks,

Jon.

HenningO

11-20-2007, 03:59 AM

Jon, a MATLAB script that uses normal load, inclination angle, slip angle, slip ratio as input and gives you lateral and longitudinal force is included with the data. The non-dimensional model is described in RCVD.

The same script can be used to create tire curves as well.

Jonny_B

11-20-2007, 04:52 AM

OK thants good. Finally, how long will it take for the disc to be posted to us (need it ASAP), and are we directly given all of the coefficients that we need to construct tire curves for each of the tested tires?

Thanks,
Jon.

HenningO

11-20-2007, 05:09 AM

All the coefficients are in *.mat files called by the script. Each tire has its own *.mat file.

Edward M. Kasprzak

11-20-2007, 06:52 AM

A few posts ago someone mentioned creating a private forum for FSAE TTC members only. Does anyone know how we could set this up? I like the idea.

For me, I'll have updates to the MRA model to ship shortly, and SES has also sent me a document clarifying sign conventions that I'd like to get to everyone. Posting in a secure forum would be the easiest way to distribute these since the files will not be large.

I'd like to see all the FSAE students be able to talk more openly about their data and models. Let me know if you have any ideas on setting up a secure site. Seems like the hard part will be verifying that those logging on really are from a member school....

Oh, and thanks everyone for respecting the terms of the FSAE TTC agreement (not posting data, etc.) We've had almost no issues. You'll have plenty of legal agreements to abide by and proprietary knowledge to protect in your upcoming careers--it's nice to see that our agreement has been so well-respected.

HenningO

11-20-2007, 12:23 PM

About the private forum, I guess FSAE TTC has an email contact to all partcipating schools, by sending login info to that adress would be one way.

I don't know who manages this site? Adding another password protected forum alongside all the existing ones makes most sense IMO.

Matthias_W

11-24-2007, 02:59 AM

Hi,

Does anyone know what to do?
I got this error using the ExpansionType 5 with any of round 3 tire data file:

??? Error using ==> rdivide
Matrix dimensions must agree.

Error in ==> ...\fromMillikenResearchAssociates\expand_mrandim. p>expand_mrandim at 792

Error in ==> call_mrandim at 208
MZ = expand_mrandim([5,units],NDIM5,[FZ,SA,IA,0,mu]); % Call to MRA Nondimensional Tire Model

And I got this error using metric units with any of round 3 tire data file:

??? In an assignment A(I) = B, the number of elements in B and
I must be the same.

Error in ==> ...\fromMillikenResearchAssociates\expand_mrandim. p>expand_mrandim at 741

Error in ==> call_mrandim at 104
FY = expand_mrandim([4,units],NDIM4,[FZ,SA,IA,0,mu]); % Call to MRA Nondimensional Tire Model

We would very thankful if someone could help us.

Thanks!

HenningO

11-26-2007, 04:23 AM

Matthias_W,

That's a known error in dataset #3, as Dr. Kasprzak (of the FSAE TTC) mentioned earlier in this thread, they are working on a fix for this.

Edward M. Kasprzak

11-26-2007, 06:32 AM

Regarding a private forum for FSAE TTC members:

If there is a student who would like to volunteer his/her time to set-up and maintain such a forum the consortium leadership would be interested in hearing from you. Please e-mail me directly. We'd like to establish the position of "Student Associate", similar to the position Denny Trimble occupied when the consortium was founded (and before he graduated). Duties would include:

+ Establishing a private forum for the FSAE TTC
+ Establishing access to this forum for consortium members
+ Maintaining the forum membership list as new schools register for the consortium and as contacts at schools are updated. This happens regularly.
+ Watch for students openly posting data outside of the private forum and pursue corrective action

We have a contact person and e-mail for all the schools, so this can be used to establish sign-in rights and password protection. The only issue there is that some of the contacts are a few years old now and may no longer be relevant. These will need to be updated.

In return, you will be making a valuable contribution to the FSAE community, will have even more work to do and will exprience occasional throbbing headaches because of it. You'll also be listed on the FSAE TTC website as the Student Associate and the consortium leadership (and member students) will say all sorts of nice things about you--assuming you do a good job.

Finally, we're open to a discussion on whether or not this position merits a small monthly stipend. The directors are all-volunteer, but this may be a large enough and important enough task to offer lunch money to the student who jumps onboard. What do you students think?

I'm looking forward to hearing from anyone who's interested.

Crispy

12-12-2007, 05:50 PM

A question about the non-dimensional model and slip angle peaks.

If you do not see a peak for a slip angle sweep at a given load then you will not know the peak coefficient of friction for that load. In this case, how would you go about normalizing that slip angle sweep?

Jonny_B

12-13-2007, 01:20 AM

Hi,

I'm very interested to know how other UK teams managed to pay for this data..? It seems they wont accept any form of payment that my university can provide!

Thanks,

Jon.

GooDLuC

12-30-2007, 08:51 AM

What's going on with the MRA update?

John Fratello

02-25-2008, 08:32 PM

I'm also wondering about the MRA update. Did anyone else notice that the slip angles and slip ratios seem to have the wrong sign in the Goodyear Round 3 data. I didn't have any problems with the Round 1 nondimensional solution, but round 3 is tearing me up.

Also, any more word on the private forum?

geoffrey_khoa

02-26-2008, 06:26 AM

VTSpensh: it is just a bug and i had mailed Mr Milliken some time back. he said he would get it solved as soon as he has time...

nos

03-06-2008, 04:36 PM

Hi all,

I've been playing with the MRA nondimensional model and comparing it to the raw data. I've found that for the Avon (tested in round 2), the camber effect in the raw data differs quite a lot from the camber effect produced by the MRA model (taking into account the various sign conventions etc).

Is there a way to account for this by varying any of the parameters in the MRA model? Ie, be changing anything in the tyre .mat file? I'm keeping everything within the range of the test parameters.

Thanks,

Dean McGeary
Redback Racing - UNSW FSAE

exFSAE

03-06-2008, 08:41 PM

Not sure how kosher it is discussing actually data trends in public forum.. but..

1) Do you need an accurate model? For a lap simulation tool? I would imagine at the FSAE level most benefit can be reaped by characterizing the raw data

2) Have you looked at the Pac96 / MF5.2 (whichever it is) coefficients provided by Stack? How does that fit overlay with the raw data, and with the MRA model?

I am not that familiar with the MRA model, but I do know you can go in and manually tweak coefficients for the Pac96 model to change curve shape, camber sensitivity, blah blah blah. Stack provides the underlying equations so you can at least see how everything works. Isn't encrypted into a P-file.

3) Are you staying within the range of test data? Ie are you trying to extrapolate trends up to say 8-9 deg of camber when the test and fit data only go to 4?

DougMilliken

03-08-2008, 06:57 PM

Hello to fase.com,

Dr Kasprzak is very busy with other work these days and recently he asked me if I could take on some of his TTC volunteer work, including watching the fsae.com forums. So I've just joined and will monitor this thread, and maybe some other TTC related threads if I have time.

Looking back through some recent posts, the topic I'd like to pursue is a secure forum for TTC members to post data and modeling questions/results. If it was really secure, maybe it could also be a distribution channel for future data--sending out 150+ DVD's after the next test is not something we volunteers are looking forward to doing! Has anyone given this more thought?

Re: MRA model basics -- anyone interested in the MRA-provided tire model can get a general idea from RCVD Chapter 14.

-- Doug Milliken for the TTC

BillCobb

03-22-2008, 02:13 PM

FWIW: I have some experience with the primitive tire model used Bosch/Lapsim. It's Pacejka with just 4 coefficients for each tire and well suited to FSAE car lap time optimization. Folks in the Racing group use it (full blown version) for many of their own vehicles and have a high regard for it (for reasons already mentioned: operating at the limit. While there is no Lapsim input for Mz or Mx, I can show you how to produce Lapsim tire model coefficients for Fy, Mx, and Mz, slip, camber, LR, etc from the Calspan datafiles using Matlab if anyone is interested. (not sure how to post code, though, unless its with a Forum blast. I personally have not yet looked at the TTC data but am very familiar with Calspan .tir and .dat files. I suspect some extra=points seeking teams might want to run lap time sims with manageable tire model elements. I'm not dissing MRA or Pacejka'xx, or MFT, just recommending a KISS approach. The Lapsim model is high value and has a lot of low hanging fruit to be picked.

DougMilliken

03-24-2008, 07:04 AM

Bill,

Nice to see you posting here. If you would like, your Matlab code could be distributed along with the FSAE TTC data. Your code sounds like it would be a "roll your own model" alternative to the two different "canned" tire models that are currently included. Support for the free Bosch/Lapsim is a great idea.
The next TTC DVD will be assembled after the fourth round of testing and will go out to all current members (over 150 universities). This might happen this summer, depends on workload of the TTC organizers. Email me at:
doug . milliken on gmail . com
or we can continue the discussion here online.

-- Doug Milliken for the TTC

Haymo N.

04-14-2008, 12:50 AM

Hi all,
What's about the MRA update? Has anyone solved the problem with the MZ data? (Matlab Error: ˜Error using rdivide').
Currently I try to plot the data using the SES Pacejka coefficients to compare the plots with the MRA output. Has anyone of you already done this?
Cheers, Haymo

DougMilliken

04-16-2008, 01:59 PM

Haymo,
Unfortunately for you, our paying work comes before volunteer work for FSAE/FStudent. Dr Kasprzak is very busy and I can't predict when he will have time to look at the model we provide.
Plotting the MRA model against the SES model is an interesting idea--maybe you can post some comments on your general results?
-- Doug Milliken

duckei

04-18-2008, 08:57 AM

Hi all,

This is a bit early...But,

Any thoughts to new compounds for round 4? We feel some of the new Hoosier B compounds should be on the list:

43161R25B 20.0x8.0-13 road racing slicks R25B compound

43162R25B 20.5x7.0-13 road racing slicks R25B compound

Also, On behalf of Rensselaer I would like to thank you Dr. Kasprzak and Doug Milliken for your work. We understand you are busy and have lives as well.

Respectfully,

-Ian

BillCobb

04-18-2008, 12:54 PM

Can RPI get help from Alumni ?

Bill Cobb
'71-'72

duckei

04-23-2008, 05:35 AM

I wouldn't be opposed to it. http://fsae.com/groupee_common/emoticons/icon_smile.gif

Respectfully,

-Ian

ReinierJ

05-06-2008, 01:55 PM

Dear all,

At the moment I'm trying to implement the TTC data into an ADAMS model I'm making of our FSAE car.
Doing this I ran into the following problem: TTC delivers a Pacejka 96 model, whilst ADAMS comes with 89, 94 and 2002. After investigating all models by reading the TTC/ADAMS manuals and browsing the internet I came up with the following partial solution:

Take the 2002 model and put the 96 coefficients in. Take all unknowns 0, and disable transient behaviour. This effectively creates a 96 model in the 2002 one. However a number of things cannot be ignored, but are also not present. The TTC data does not include (or I have not been able to find) the vertical damping, peak value and high/low load variation of the rolling radius. These last three might be extractable from the TTC data. But I have my doubts about the damping. ADAMS does need these however.

Also the PKy2 < 0 (Hoosier 20.0x7.5-13 tires) is not accepted by ADAMS.

It amazed me a little that this problem has not popped up on any of the fora before. Is there a solution to this ("known?") problem (converting '96 to '02)?
As well as why PKy2 has the wrong sign by ADAMS liking?

Thanks in advance for any help / pointing me in the right direction.

BillCobb

05-06-2008, 09:02 PM

Gimme a tire brand/size/construction that you are wanting to run an experiment on. If you have Matlab, I can maybe provide you with a MF5.2 pure slip fitting routine. A Roll Your Own, so to speak. It that works for you, you will be able to quickly figure out how to do the rest, given 'good' quality tire data. Keep this phrase in mind: "Good Tires Test Well". I suppose that also could mean "Good Tyres Test Well", too !

Interested?

I beleive the answer to your question is as simple as "No ones doing it".

exFSAE

05-12-2008, 07:42 AM

I still think it'd be cool for Round 4 (whenever that is) to do some wet testing. Inevitably it tends to rain on at least one day of driving in Detroit.. and from the Oz comp apparently even they are not exempt from bein rained on. Good rain tire would give a pretty big advantage.

Would also just be cool to see what the difference in grip levels is, breakaway traction effects, etc.

Matthew Bell

07-07-2008, 03:24 PM

I've been trying to get in touch with Dr. Kasprzak to update our contact information, but have never gotten a reply. We never received a DVD for round 3, but we did get the update ADAMS model via an alum of the team that was kind enough to forward the data to our adviser. Does anyone know who I should contact to make sure that our info is correct?

Edward M. Kasprzak

07-07-2008, 07:12 PM

Matthew,

I haven't seen an e-mail from you...don't know why. I'll send you a personal correspondence.

We can check the mailing address and arrange for another Round 3 DVD to be sent. Be sure to look for it when it's expected to arrive. University mail systems are, in general, above average at making things disappear.

It's true I've been very busy this year, but I'm still around and putting time into the FSAE TTC as I can.

Regards,
Edward

GooDLuC

07-07-2008, 07:37 PM

Hi Dr. Kasprzak

Is there an expected date for round 4 testing?

Also can we still expect an update to correct problems found with round 3 tire models?

Thanks!

DougMilliken

07-08-2008, 04:43 AM

GooDLuC / UniversitÃ© Laval --

No date set yet for Round 4 tests, we will post here (or start a new thread) when we know more.
Likewise for our MRA-donated models.

-- Doug Milliken

Matthew Bell

07-08-2008, 07:30 AM

Dr. Kasprzak,
E-mail sent! Thanks again.

MalcolmG

07-13-2008, 03:51 AM

Looking back through some recent posts, the topic I'd like to pursue is a secure forum for TTC members to post data and modeling questions/results. If it was really secure, maybe it could also be a distribution channel for future data--sending out 150+ DVD's after the next test is not something we volunteers are looking forward to doing! Has anyone given this more thought?

It's a bit disappointing that nobody else has put their hand up for this. Now is a really bad time for me to go through the quite time consuming task of setting up a good facility for this, with a lot of work ahead of me in the next few months, but if nobody has taken on the job by the end of the year then I'll do it.

DougMilliken

07-14-2008, 03:27 AM

Malcolm,
Thanks for your offer of help with a secure server or other system. This problem has not gone away, and the task of data distribution obviously gets a bit larger every time the TTC gets a new member.
-- Doug Milliken

Chris Lane

07-29-2008, 07:53 AM

Can I suggest a method of distributing this sensitive data?

Why not set up a very simple website using a CMS (Content Management System) like Joomla or Mambo? These systems have secure user databases built in and any number of 'admins' can authorise/deauthorise users to certain parts of the website.

The best part is systems like Joomla are free! I used it build our team website and it took me a about 20 hours to build in total and I knew nothing about how to build a website.

exFSAE

08-15-2008, 08:26 AM

Only issue I'd see is the data can get to be pretty enormous.. given that it does come on multiple DVD's. Might be better for physical media than just web-hosted.

Bazanaius

09-01-2008, 07:25 AM

Maybe have a choice? Teams who still want hard copies of the data can indicate this. Those who are happy to download can indicate this. two DVDs is just over 9GB. Alot, but not prohibitively massive if you can get someone to host it for you.
I'd second a call for joomla or similar. Might not be as perfect as a specifically written system, but alot of the hard work is done already and saves a lot of time. Easy to maintain as well because of the good UI.

Bazanaius

09-05-2008, 02:11 AM

Hey guys,

I've tried to email Edward Kasprzak but I think he is busy at the moment, so maybe one of you guys can help me out.

Essentially, we dont have a faculty advisor as we are independant of the university. A member of staff has kindly offered to let us put his name down on the TTC application form, but would like to know what is expected of him in advance.

Could anyone let me know what the Faculty advisors contact details will be used for? Is it just to check that we are who we say we are?

cheers,

B

DougMilliken

09-06-2008, 01:22 PM

> Could anyone let me know what the Faculty advisors contact details will be used for? Is it just to check that we are who we say we are?

From memory, I think the only time the TTC contacted a faculty adviser was if we were unable to contact the team otherwise...some FSAE students actually graduate<grin>. Your "reluctant staff member" might have to update email for your team contact, nothing more.

Please send TTC membership emails to Dr Kasprzak and cc to me-- doug . milliken at gmail

New topic: It's nice to see the recent posts on ways to improve the TTC data distribution-- please keep the ideas coming.

-- Doug Milliken for the TTC

Bazanaius

09-08-2008, 03:34 AM

Hi Doug,

thanks for your reply - the staff member is actually not very reluctant at all, however it is the situation with the department that makes it hard for it to be 'official'.

I'll get the form and cheque together and let you know when it's on its way.

cheers,

B

exFSAE

09-27-2008, 09:51 AM

Anyone know if the aligning torque MRA expansion ever got fixed?

DougMilliken

09-28-2008, 06:44 AM

First I put on my MRA hat (and put the TTC hat to one side). Thanks for your interest in the model we donate, I'm curious how your team would like to use it--can you give a little detail?
To your question, no, we have not updated our tire model, too busy with regular work. Current plan is to do everything at the time of Test #4. I believe that the aligning torque problem is with the data files, some work correctly and some don't (but that is only from memory, I didn't check archives).

Back to the TTC hat, there is some activity starting up for the next round of testing, but still no hard dates.

-- Doug Milliken

Anvit Garg

10-24-2008, 01:11 PM

Hello:

I have just submitted the registration form. I was wondering if anyone knew the average turn around time for the whole process of acquiring the tire data?

I was hoping for an electronic means of payment to speed it all up.

Thanks.

DougMilliken

10-25-2008, 04:46 AM

Originally posted by Anvit Garg:
I have just submitted the registration form. I was wondering if anyone knew the average turn around time for the whole process of acquiring the tire data?

I was hoping for an electronic means of payment to speed it all up.

It's often less than a week in USA, longer to other countries depending on airmail time and my availability--I travel a lot for business. It will probably take you significantly longer to figure out how to use the data (weeks, months) than it does to deliver it!

Since we are all volunteers running the TTC, one goal is to minimize our personal time, thus my request for USA checks whenever possible. For example, wire transfers (bank-to-bank) often take longer overall because of the lack of documentation or other reasons.

As noted earlier in this thread, Dr. Kasprzak is very busy, so I suggest that you cc your registration form to me when you email it to him, doug dot milliken, gmail dot com.

-- Doug Milliken for the TTC

jrickert

11-15-2008, 05:04 PM

The load control on some of the runs is REALLY bad.

BillCobb

11-15-2008, 05:30 PM

Please be more specific. Need a file name. I would like to take a look at this. Thanks.

Mike Macie

11-15-2008, 06:28 PM

Originally posted by jrickert:
The load control on some of the runs is REALLY bad.

I believe this was only during Round 1 of testing. This issue was resolved for later rounds. Remember, the normal loads are a lot smaller then what Calspan normally tests. But yeah it was pretty bad. I think i remember it being off +/- 75-100lbs

jrickert

11-16-2008, 09:44 PM

Round 1 and 2 are both really bad. Even a few runs from 3 are messed up. If you plan on overlaying graphs of different tires under the same conditions its pretty much impossible without some curve fitting etc. I would suggest that round 4 go back and redo some of these tests. On the up side it gives a wide range of normal loads to look at.

DougMilliken

11-17-2008, 05:18 AM

> The load control on some of the runs is REALLY bad.

Some quick comments:

* Unlike data that comes in textbooks, tire data is messy. The real world is often messy, and if you plan a career in engineering I suggest you get used to it. This is why there are many different schemes to model experimental data.
* Even tire data with good test control is normally modeled, so that intermediate conditions can be predicted. Can't remember the last time that we used raw tire data directly.
* Some of the TTC data is a little harder to model than normal. As noted earlier, the FSAE load range is much lighter than most tests run at Calspan which makes it a challenge for the machine operators. This is why the TTC organizers and other volunteers have provided "canned" models that you can use to get started.

-- Doug Milliken for the TTC

Anvit Garg

11-17-2008, 10:29 AM

I have been playing around with the MRA model so far and have had some luck with producing plots that match the raw data.

As judging is concerned, do the judges expect you to construct your own models/curve fits?

We are new to all of this and the "rawness" of the data is intimidating!

How is the progress for an alternate forum dedicated to TTC subscribers?

DougMilliken

11-18-2008, 04:10 AM

As judging is concerned, do the judges expect you to construct your own models/curve fits?

I can't speak for other design judges, maybe some others will add their thoughts? In my case, I expect you to be able to defend your design and engineering decisions.

For example, if you choose to model the tire data in-house (a tough project) this will consume some of your total time for engineering--I might ask if this was a good choice vs. using your engineering time/budget on some other aspect of your car. Going the other way, if you choose to base your car design on one of the "canned" tire models, I might ask if you made any checks against the raw data (not too time consuming) to convince yourself that the model was working correctly.

See RCVD Chapter 10 for some more detailed thoughts (written about 15 years ago).

Progress on setting up a TTC private forum will continue to be discussed in this thread. We are still looking for someone to volunteer to help out. None of the current TTC organizers have time or resources to set this up ourselves.

-- Doug Milliken for the TTC

Anvit Garg

11-18-2008, 11:44 AM

See RCVD Chapter 10 for some more detailed thoughts (written about 15 years ago).

I am interested in helping set up a secure forum.

All we need to do is install that vBulliten php code on donated web space, I believe it is secure and widely used. This wouldnt change the medium of distribution, but would allow free chat regarding this data.

My only question is: could google catch the posts and cache them? Is there a way to prevent that? I ask this because if you search on google, it will display hits that actually search the FSAE forums.

I cant be the only one helping though because I am apart of the Army national guard and might have to leave for a while, so maybe we can get a couple more people and start making this happen.

Brian S

11-19-2008, 08:23 PM

WSU can host a forum for discussing TTC stuff in private.

Over the summer we set up a private forum for our team, one of the options is if you want to allow the search bots in, disabling this makes it so that nothing in it will turn up in Google or any other search engine.

Kelvin

11-21-2008, 04:32 PM

I've been looking at the Milliken data and I was wondering is there a way to input your own numbers?

Like, let's say I'm looking at the longitudinal force for a specific tire. Is it possible to input my own normal load, mu, etc??

Any help would be great.

Thanks,

scott_rfr

11-21-2008, 06:37 PM

Yupp, just modify the code some. There is a section that has Fz=-[50:50:350] just replace that with a single load. Same for IA, mu etc...just keep in mind this is IA not camber so keep your signs right!

Also if your interested in a single point above the area that does the plotting there is some commands to output a specific point of interest.

Scott
Rutgers FSAE
Suspension Team Lead

exFSAE

12-14-2008, 11:17 AM

Budget sheet stop updating? Or has there been zero buy-in since Feb?

Anvit Garg

12-14-2008, 01:24 PM

Any new news with the TTC forum?

I finish finals this week and if nothing has happened, I will have time around the end of this week to invest towards making a private forum happen.

I currently have my team's forum hosted for free through freeforums.org, no php coding experience necessary.

DougMilliken

12-15-2008, 09:02 AM

Originally posted by exFSAE:
Budget sheet stop updating? Or has there been zero buy-in since Feb?

Thank you for the reminder--TTC accounting is in good order but due to a communication slip we failed to update the spreadsheet on the website. Reload the page and try now. There are about 40 new members since Feb 2008.

http://www.millikenresearch.com/fsaettc.html

-- Doug Milliken for the TTC

DougMilliken

12-15-2008, 09:19 AM

Originally posted by Anvit Garg:
Any new news with the TTC forum?

I finish finals this week and if nothing has happened, I will have time around the end of this week to invest towards making a private forum happen.

I currently have my team's forum hosted for free through freeforums.org, no php coding experience necessary.

Thanks for following up, it's nice to finally have a choice! We also have an offer from Brian at Washington State University FSAE to set up a TTC site on their private server. He and I had a short discussion including the idea of having both a forum for discussion and a separate wiki for longer term reference.

I wonder what the pros and cons are between using a private server and a public service like freeforums.org ? Feel free to discuss here on FSAE.com, or email me if you prefer at doug dot milliken on gmail.

-- Doug Milliken for the TTC

exFSAE

12-15-2008, 01:08 PM

I would think a public service might be idea. Given the turnover rate of FSAE students, changes in departments etc, for long-term stability and maintenance a public location could work very well.

Anvit Garg

12-15-2008, 04:17 PM

I agree, long-term wise it would be best to have a public host.

But then that is another cost. I believe not too much since you do not have to register a new domain if you host through a public service.

Also if the private server crashes, assuming there are less frequent back-ups, that would be another problem.

Anvit Garg

12-15-2008, 04:20 PM

Originally posted by DougMilliken:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by exFSAE:
Budget sheet stop updating? Or has there been zero buy-in since Feb?

Thank you for the reminder--TTC accounting is in good order but due to a communication slip we failed to update the spreadsheet on the website. Reload the page and try now. There are about 40 new members since Feb 2008.

http://www.millikenresearch.com/fsaettc.html

-- Doug Milliken for the TTC </div></BLOCKQUOTE>

I think you might have missed University of Houston, we had purchased the data recently.

DougMilliken

12-16-2008, 07:27 AM

Originally posted by Anvit Garg:
I think you might have missed University of Houston, we had purchased the data recently.

You are on my master list, will appear the next time the website is updated.

Side note, I had trouble convincing Firefox3 to reload the page and get the updated spreadsheet, it keeps giving me an old one from page cache--finally gave up and started IE which did the job.

Brian S

12-18-2008, 11:19 AM

Originally posted by exFSAE:
I would think a public service might be idea. Given the turnover rate of FSAE students, changes in departments etc, for long-term stability and maintenance a public location could work very well.

I would think the exact opposite would be true. You are correct about turn over rates for team members, but maintaining a forum takes almost no time after it is set up, and correct my if I'm wrong, but you are no longer on a team and still active within the FSAE community. Even if a public server is used, you still need someone to maintain the account, so turnover of whoever is running it is an issue either way.

I have always tried to stay away from "free" hosting services. I have never seen the one mentioned, but my experiences with places like that in the past have not been great. From what I have seen you can't get free service and good service. Typically to cut costs they will over sell their equipment, so reliability becomes an issue. Also, given that they aren't charging for their services, where does their revenue come from? Running a commercial server costs money, both in people and real estate. I have a lot more confidence that a college departmental server will still be there is 5 years than a free hosting company.

Setting up a forum requires little knowledge of PHP, mostly you just have to set some variables with information about the database location and username/password. Anyone who can figure out how to work with TTC data in Matlab should be able to handle this without even thinking about it.

This may or may not be an issue, but I'm somewhat paranoid about sending data to random people across the internet. If we are trying to set up a private forum to discuss the tire data, what makes you trust a free hosting company with that data?

Doug and I have also been talking about having a wiki in addition to the forum as a place to answer common questions. This would probably be hard to do with a free forum hosting place.

OK, that’s it for my rant. Personally I would rather one of the teams’ hosts this forum, but either method would probably work just fine.

exFSAE

12-20-2008, 09:20 AM

Brian-

You are correct that I am no longer on a FSAE team. I am however still directly active in the community.

All I know is my university's own experience. With the couple times our computer lab was upgraded, servers changed over, admins changed, access rights, etc.. it would have been tough to keep something steady over time.

In any event, I didn't say "free," I just said public.

Just my 2 cents.

bahous

01-07-2009, 02:35 PM

My university obtained the TTC tire data two years ago but it is only this year that we decided to try to make use of it.

I've been doing some simple simulation on MATLAB to try to get some data that makes sense and that can be useful.

Here's a quick explanation of what I did and what my problem is:

I'm running test3 MRA goodyear 20x7x13 - 7 rim data at 12psi, 2deg IA. I'm running ExpansionType = 4; % FY = f(FZ,SA,IA,mu)

instead of having a loop for the normal load, i'm setting it to 245lb. when the graph is plotted, my peak does not match my graph. what i mean is that the curve's peak is somewhere, and the dot that indicates the peak is off by 1deg SA and 100lb of FY. is this correct or there's a problem somewhere?

MalcolmG

01-11-2009, 04:17 PM

I've found the peak finder in the MRA models appears to be temperamental at best. If you use the loop to plot graphs and peaks for a couple of different tyres, you'll see that sometimes you see peaks that are no where near the graph, sometimes even of reversed sign. I would definitely believe the apparent peak on the graph rather than that indicated by the peak finder.

It's hard to know why it happens because the code for the models is a 'black box', but I'd suggest if you want to use the peak values for some other purposes, then you generate them yourself by looping through several slip angles and then simply reading the highest value in the output matrix (I haven't tried, but I bet there's a MAX function or something built in to Matlab that'll make life easy)

Brian S

01-21-2009, 12:45 PM

MalcolmG

01-26-2009, 05:52 PM

excellent. Do people feel it's sufficient identification that someone has an email address that is from a member university? Auckland has around 30,000 students, all of whom have @aucklanduni.ac.nz email addresses, but less than 30 are in the FSAE team. Should there be an extra identification required by an assigned member from each university? It's a lot more work, guess it depends what kind of information will be posted and how private it is desired to keep this data. Is there any consensus as to what is and isn't acceptable to discuss/post on the forum?

Zac

01-26-2009, 06:08 PM

There's also the issue of what to do about industry guys that have supported the TTC (Goodyear, Hoosier, Stackpole, etc.)

Brian S

01-26-2009, 10:56 PM

Malcolm, you bring up an interesting point about other students at a member university. I hadn't thought of that, do you think other students trying to join will actually be an issue? If you have a simple way to ensure that someone is actually on the FSAE team, I'm all ears. Keep in mind that there are 199 members, so simple is key. I don't know now current the contact info is either, so telling everyone what the method is could also be a problem. Not saying its impossible, just that it would be a lot of work.

Zac, I'm going to take the easy way out and say that I'll leave that up to Doug and the other TTC organizers. Right now Doug Milliken, Bill Cobb, and Dr. Woods have accounts.

exFSAE

01-27-2009, 05:19 AM

Bill Cobb is a TTC organizer?

BillCobb

01-27-2009, 05:45 AM

Supplies.

http://www.youtube.com/watch?v=nmo_dkNZIHM

DougMilliken

01-27-2009, 07:00 AM

Originally posted by Brian S:
Malcolm, you bring up an interesting point about other students at a member university.
....

As I've been interpreting the TTC license, once a university/college/school joins, the data is available to any researcher at that institution. For example, a couple of TTC memberships have been paid by university libraries (clever way to stretch an FSAE/FStudent budget!) and the librarians maintain the data in a location that is only available to their students & faculty. This new private forum may be a good opportunity to revisit this policy if anyone feels that there is abuse of the TTC license?

There's also the issue of what to do about industry guys that have supported the TTC (Goodyear, Hoosier, Stackpole, etc.)

I think it's to everyone's advantage if the TTC supporters are allowed to join the private forum--if anyone has a reason to object perhaps they could post it here?

In answer to another post, Bill Cobb is the newest addition to the list of TTC supporters.

-- Doug Milliken for the TTC

Edward M. Kasprzak

01-27-2009, 07:40 AM

FYI, I'm still a TTC organizer, too. Just slow to sign-up on the forum. I've been working on some other changes to how the TTC operates which should benefit everyone. Info coming soon....

Nice to see the private forum is up and running!

scott_rfr

03-10-2009, 04:45 PM

What's up with the registration? It's been awhile since I applied and have not heard anything back yet.

Scott

DougMilliken

03-11-2009, 07:18 AM

Originally posted by scott_rfr:
What's up with the registration? It's been awhile since I applied and have not heard anything back yet.

Please email a copy of your registration form to me, I don't think I have it?
-- Doug Milliken for the TTC
doug dot milliken at gmail ...

Brian S

03-11-2009, 09:47 AM

Scott,

Are you talking about TTC registration or the forum registration?

I see that you have two forum accounts, both have been activated but have never logged in. Did you get any emails from the forums? There should be one right after you register saying your account is waiting for approval, and then one after your account is activated. Maybe it has been flagged as SPAM?

There are 13 people who have registered but never logged in. If you have registered and not received an email back saying your account has been activated, send me an email or PM and I can reset your password and manually email it to you.

EDIT

OK, I think I know what was wrong. I'm going to resend activation notices to everyone who hasnt logged in, let me know if you dont get them.

scott_rfr

03-11-2009, 10:06 AM

Brian,

I was referring to the forums, sorry I should have been clearer in my first post. The reason I have the two accounts was that I never received the email notification of your approval. I created the second account because I tried to contact you that my account had not been activated but it did not recognize my email. I just figured that the first time there had been some start up glitches.

BTW: It's working now.

Scott

jpusb

09-29-2009, 12:30 PM

hey Brian, at my team (Universidad Simon Bolivar from Venezuela) we do not have @universityID.com email adresses but instead we have something like: yourname.fsaeusb@gmail.com

It's a GMAIL address and just has the .fsaeusb to kinda ID the university/team name. How could I register to the forums with that address?

Please let me know ASAP

Edward M. Kasprzak

09-30-2009, 04:16 AM

By the way, the next round of tire testing is upcoming, currently scheduled for the week of Oct. 19th. There's a separate thread for it--look for "Round 4" in the thread name.

DougMilliken

09-30-2009, 05:34 AM

Originally posted by jpusb:
hey Brian, at my team (Universidad Simon Bolivar from Venezuela) we do not have @universityID.com email adresses but instead we have something like: yourname.fsaeusb@gmail.com

Send me a new Registration Form with updated information and faculty contact, download from
http://www.millikenresearch.com/fsaettc.html

-- Doug Milliken for the TTC
doug dot milliken at gmail

jpusb

09-30-2009, 03:37 PM

OK will do ASAP.

So, if our technical director and myself would want to join the forum could we do so with each one's gmail address? (both under the team's format name.fsaeusb@gmail.com)

Thanks in advance

DougMilliken

11-27-2009, 08:07 PM

TTC Round 4 data is now available and TTC members are encouraged to check the TTC Secure Forum for details.

The TTC home page has been updated with a list of the tires/constructions tested as well as a free download that describes Round 4 in more detail. Also includes instructions to find the Forum. Start here,
http://www.millikenresearch.com/fsaettc.html

Note--I'm also going to post this same note in the Round 4 thread...and it would be nice if the FSAE.com moderators made the Round 4 thread sticky (and turned this Round 3 thread back to normal.)

-- Doug Milliken for the volunteers that run TTC
doug dot milliken at gmail

sbrenaman

12-01-2009, 02:20 PM

I have the TTC data on my desk here, but no luck registering for the http://sae.wsu.edu/ttc/ forums. I filled out an application but haven't heard back.

sbrenaman

12-01-2009, 02:28 PM

Thought I replied but maybe not.

Anyway, Portland State is registered for the TTC (I have the CD here on my desk), but I'd like to get registered and get help from the TTC Forums hosted by WSU. Any word on the status of the forums admin?

DougMilliken

12-02-2009, 07:56 AM

Have you tried to log in to the TTC forum? There was (or still is) a bug in the forum software and some of the auto-notification emails were not sent.
-- Doug Milliken for the TTC

sbrenaman

12-02-2009, 11:15 AM

Wow. I don't know what my damage was the other day, but it works fine now.
http://fsae.com/groupee_common/emoticons/icon_rolleyes.gif

Thanks

Ginga_Ninja

03-05-2011, 01:40 AM

Originally posted by Edward M. Kasprzak:
Allow me to put my Milliken Research hat on for a minute (I've worked there since '96) and talk about the MRA Nondimensional Tire Model. This model is included on the DVDs and is generally described by Chapter 14 of the Milliken's "Race Car Vehicle Dynamics". The Nondimensional scheme models tires on a more fundamental level than just trying to match the measured curve shape. One of the parameters that is modeled is the friction coefficient, defined as the peak of the lateral force curve divided by the normal load. This value can be multiplied by a surface friction value to scale the data up or down. If scaled down, the resulting tire data has the same cornering stiffness as the original data but lower peaks occuring at new (lower) peak slip angles. This is representative of how real tires behave. Done this way, the Calspan surface friction coefficient is defined as "1.0" and your surface may be "0.7" or something like that. If you try this with the FSAE TTC data you may find peaks occuring for reduced surface friction coefficients on curves where the raw data doesn't show a peak on the test machine.
Edward

Talk about bringing a thread back from the dead. I searched a few threads but the above from Edward discussed it the best, so here it is! Not to mention he wrote the book I am using.

I am working through some of the RCVD problems, answers and experiments at the moment. I’ve done chapter 14 and was wondering about further application of the surface grip factor that you discussed above. My query is the best way to apply the track friction factor.

From the sample data the values for coefficient of friction were calculated in Part c (1.91 at 700 lb down to 1.281 at 2500lb). Do you apply the factor to this and generate new values of Fy, Mz, Mz and Slip Angle (from Eq 14.1 – 14.4 from RCVD) from the normalised data?

To me this seems logical. For the data from Question 14.2.h I changed the COF from the assumed to a higher value and it maintained the cornering stiffness in the linear range, just gave a higher peak Lateral Force at a higher slip angle. So that bit makes sense.

If this is the case, do you apply a linear scaling to the COF values at each load point? (So with the values from part c, a 0.7 factor would give 1.337 at 700 lb down to 0.8967 at 2500lb)

Thoughts? I look like a kid stuck with his homework!

Thanks

GN

Edward M. Kasprzak

03-05-2011, 03:32 AM

The friction coefficient (mu) values in Chapter 14 of RCVD describe the tire-road interaction and are derived from the peak force at any given operating condition. This mu can be multiplied by a surface factor describing how your road is different from the test surface. We create the model assuming that the Calspan surface is "1.0". For the TTC data, feedback from students indicates a value around 0.65 is appropriate for this mu modifier. For our professional customers the value can range from around 0.65 up to 1 or even a little bit higher--it all depends on the road surface, the tire and the application.

Ginga_Ninja

03-05-2011, 06:44 PM

Thanks for the quick reply. I probably didn’t ask the question properly. I pretty much understand how you need to ‘scale’ data from the test rig to fit with track data; I was more checking my workings were right.

I took the data from the Ch 14 question then applied a 0.7 Factor to the values of COF at each load and graphed it on top of the original data (the blue dots)
http://img835.imageshack.us/img835/8686/tyredata.jpg

Is that what you would expect for a lower grip factor? The cornering stiffness values are the same and the peaks are lower and smaller slip angles.

On top of that, the blue dots represent the bounds of the normalised slip angles from the original data. That is, for 700 lb, the normalised slip angle goes to 2.9 from the original data but for the highest load it only goes to 2.1.

The black dots represent slip values created from normalised slip angles greater than those from the data through the magic formula (if you know what I mean?).

Is it valid to extrapolate data beyond the normalised slip angle or should I just use the data within the boundary of the source data. Sorry this is written so poorly!

Thinking about the lab vs. track friction, I can imagine the resultant tyre data would change for a given track. Take the laptime differences from the Abu Dhabi round to the tyre testing that was done afterwards, where the rookies were going quicker than the main guys qualified.

From this you could say that for lower grip tracks which had the same style corners, you could need different steering geometry (ackerman et al), pressures, cambers etc?

ben

03-06-2011, 02:31 AM

This is a key point. We can quite happily work with a value around 1 because GT compounds are quite hard so don't automatically generate unrealistically high mu on the flat-trac.

If you don't do any work to validate the level of friction on track vs. machine the tyre data is of limited use.

Ben

Ginga_Ninja

03-07-2011, 01:56 AM

I replied but it needed to be approved and hasn't been? Is that because there is a link?

Thanks for the quick reply. I probably didn’t ask the question properly. I pretty much understand how you need to ‘scale’ data from the test rig to fit with track data; I was more checking my workings were right.

I took the data from the Ch 14 question then applied a 0.7 Factor to the values of COF at each load and graphed it on top of the original data (the blue dots)

img835.imageshack.us/img835/8686/tyredata.jpg

Is that what you would expect for a lower grip factor? The cornering stiffness values are the same and the peaks are lower and smaller slip angles.

On top of that, the blue dots represent the bounds of the normalised slip angles from the original data. That is, for 700 lb, the normalised slip angle goes to 2.9 from the original data but for the highest load it only goes to 2.1.

The black dots represent slip values created from normalised slip angles greater than those from the data through the magic formula (if you know what I mean?).

Is it valid to extrapolate data beyond the normalised slip angle or should I just use the data within the boundary of the source data. Sorry this is written so poorly!

Thinking about the lab vs. track friction, I can imagine the resultant tyre data would change for a given track. Take the laptime differences from the Abu Dhabi round to the tyre testing that was done afterwards, where the rookies were going quicker than the main guys qualified.

From this you could say that for lower grip tracks which had the same style corners, you could need different steering geometry (ackerman et al), pressures, cambers etc?

Edit: Yeah it's the link. Removed the initial part, should be able to put it together from there.

Ginga_Ninja

03-07-2011, 01:56 AM

http://img835.imageshack.us/img835/8686/tyredata.jpg

Edward M. Kasprzak

03-07-2011, 04:11 AM

Your plots show the expected response to a change in surface friction in the Nondimensional Tire Model.

In general terms, extrapolation of almost any model is possible--but always dangerous. You must think about how each part of the model behaves outside the range of the data. Do the equations diverge from expected behavior, begin to oscillate or go asymptotic beyond the tested range? How far can you extrapolate before these kinds of things happen? Before you try extrapolating any kind of model you need to understand how it's going to perform--people make a lot of bad decisions when they use models incorrectly in the extrapolation space.

Your last comment about the effect of grip on optimal settings is a good insight on your part.

dela

04-12-2011, 08:49 AM

Edward M. Kasprzak

04-12-2011, 01:27 PM

I'm not sure what the individual tire manufacturers make available. I suggest visiting their websites and contacting their representatives.

Your school is welcome to join the TTC at the usual rate (not free: US$500). The terms of the TTC agreement allow the data to be used for non-commercial purposes at the school which purchased a membership. It isn't restricted to use on SAE teams, so it could also be used for course projects and other university research.

Tests have been conducted on 10 inch tires.

Note that the terms of the TTC agreement prevent TTC members from openly sharing the data. This protects each member school's investment.

dela

04-12-2011, 04:20 PM

JT A.

08-23-2011, 04:59 PM

Has anybody else tried to register for the TTC forums lately? I applied for access a little over a week ago and haven't gotten confirmation yet.

If anybody knows a person I should PM or email about this please let me know.

whiltebeitel

08-23-2011, 09:37 PM

It took me a little under a month to get approved from the date I registered.

Edward M. Kasprzak

08-24-2011, 03:28 AM

You should hear back in a few days at most, not a month. We'll talk with the TTC forum master to see why this is happening.

DougMilliken

08-24-2011, 06:40 AM

Originally posted by whiltebeitel:
It took me a little under a month to get approved from the date I registered.
Sorry about that delay--it's not normal and we are going to try something new for registration approvals. TTC is all-volunteer run, and we have day jobs that come first, that may be what happened in your case.

General comment (not directed to whiltebeitel)--the most common cause for delay is not following the instructions, which clearly say to use a university domain email address.

-- Doug Milliken for the TTC

whiltebeitel

08-25-2011, 09:31 AM

Don't worry about the delay. I'm glad you guys take the time to provide the TTC as a resource to us. How many of us would give tire data a second look wihout it?

Some forums, Like CornerCarvers, take a similar ammount of time to get approval. for the Singnal to noise ratio I get from both the TTC and CC, I can't complain.

ocin1113

09-14-2011, 04:33 AM

it is possible to pay tire data by paypal?

i see on the account spreadsheet some teams use it but i don't find information about this payment ...

DougMilliken

09-14-2011, 05:04 AM

Originally posted by ocin1113:
it is possible to pay tire data by paypal?

Sometimes this is possible, email for details.
doug.milliken at gmail.com
-- Doug Milliken for the TTC

ocin1113

09-14-2011, 07:24 AM

ok!

thank youhttp://fsae.com/groupee_common/emoticons/icon_smile.gif

Edward M. Kasprzak

04-11-2012, 10:36 AM

As announced in the Round 5 thread, the FSAE TTC Round 5 data has recently been released on the TTC forum: sae.wsu.edu/ttc

You will need a TTC forum account to access the data. There are instructions for registering on the forum. You must be a TTC member to register.

Information on joining the FSAE TTC can be found at: www.millikenresearch.com/fsaettc.html (http://www.millikenresearch.com/fsaettc.html)

(I'm posting here since this Round 3 thread is still stickied, and Round 5 isn't.)

Ben A

08-15-2012, 03:14 AM

Hello,

i have a question:

Are the Pacejka Tire model coefficients also included in the round five for the 10 inch tires?

Or any Basic tire model that we can use in our Simulation program IPG Car Maker?

Thank you

EPMPaul

08-15-2012, 10:32 AM

The round 5 data hasn't been fit yet or at least the coefficients aren't on the forum. However there are fitting routines on there to fit a pacejka model onto the data. U might have to tweek it .. there are some issues relating to the parsing of the test run but otherwise it gives some pretty decent results.

rjwoods77

03-11-2013, 09:56 PM

The Japanese have come up with a brand new testing method that trumps all else....

http://www.youtube.com/watch?f...bedded&v=-vj0ld8rCEs (http://www.youtube.com/watch?feature=player_embedded&v=-vj0ld8rCEs)

DougMilliken

08-16-2013, 07:52 AM

This is the FSAE TTC (Tire Test Consortium) thread that used to be sticky...

Admin

08-16-2013, 12:16 PM

Sticky posts will be made sticky again sometime this weekend.
dealing with spam issues first.

DougMilliken

08-19-2013, 10:15 PM

Sticky posts will be made sticky again sometime this weekend.

The FSAE TTC just passed 350 members. Nice of FSAE.com to keep this big TTC thread sticky. A few thoughts:

+ Thanks to all the TTC contributors -- Calspan TIRF (show those logos!), tire companies, other industry supporters and volunteers...and of course all the member schools. The TTC has been far more successful than I ever imagined.

+ Not sure if your team is a member? Check the list (spreadsheet) at,
http://www.millikenresearch.com/fsaettcaccount.xls

+ After a rare outage, the TTC secure site is back up, thanks again to WSU for hosting. If your school is a member, you can register for the forum with your university domain email at, http://sae.wsu.edu/ttc/
It might take a day or two to be approved.

+ Not sure of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on this page, http://www.millikenresearch.com/fsaettc.html
To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

+ There are now funds to support Round 6, but we haven't found any good candidate tires yet. Any suggestions, please post to the secure forum.

-- Doug Milliken for the TTC

Xfsae

10-30-2013, 10:37 PM

I know it is not directly related to FSAE but since so many experts on the subject are here, does anybody have access to curves/data for kart tyres?

hsulaimon

01-20-2014, 03:07 PM

Hello,

Is it possible for a University's Library system to buy into the Consortium in order to get access for the schools FSAE team? With that, the data is provided to anyone in the university to use (but realistically only fsae would bother to look at). Does this violate any terms of the TTC?

Thank You,
Hafeez

hsulaimon

01-20-2014, 04:21 PM

Also links to registration form are dead here: http://www.millikenresearch.com/fsaettc.html.

Could someone PM me a copy?

DougMilliken

01-20-2014, 08:03 PM

Also links to registration form are dead here: http://www.millikenresearch.com/fsaettc.html

Link isn't dead from here, I just grabbed a copy of the Reg spreadsheet. It wouldn't open automatically in Excel, I had to <right-click, download-to-desktop> to get the file. Not sure, but it seems like this might be a problem with recent Firefox on Windows??

TTC data is licensed to the university/school, several university libraries have joined at the request of their FSAE team. It's important that the library not violate the TTC license by posting the data anywhere that might be accessible to the open internet...the librarians that I have worked with were very professional and easy to deal with.

-- Doug Milliken for the TTC

MCoach

01-20-2014, 08:14 PM

Doug, could I ask what the forecast is like for round 6 testing? I'm expecting to be out of university by the time it rolls around, but curiosity just struck.

hsulaimon

01-20-2014, 08:40 PM

Link isn't dead from here, I just grabbed a copy of the Reg spreadsheet. It wouldn't open automatically in Excel, I had to <right-click, download-to-desktop> to get the file. Not sure, but it seems like this might be a problem with recent Firefox on Windows??

TTC data is licensed to the university/school, several university libraries have joined at the request of their FSAE team. It's important that the library not violate the TTC license by posting the data anywhere that might be accessible to the open internet...the librarians that I have worked with were very professional and easy to deal with.

-- Doug Milliken for the TTC

Super! Thank you!

DougMilliken

01-20-2014, 08:45 PM

Doug, could I ask what the forecast is like for round 6 testing?
No current plans. Are there any new, good tire designs that TTC hasn't tested? If you have any ideas, please feel free to start a new thread on the private TTC forum, under "Tire Testing". A logical topic title would be, "Round 6 Pre-Test Discussion".

Edward M. Kasprzak

01-20-2014, 09:37 PM

SNasello

01-21-2014, 01:25 AM

I'll second Doug's comments. Currently the only untested tire we'd definitely want to test is the 7.5 inch wide Hoosier 10 (LC0 and/or R25B compounds). We like to have several tire designs in need of testing before planning another round.

There are also some new Avon 10 inch tires out since last season. They would be very interesting to see tested, however the OD is only ~16 inches, which might cause problems with the machine if I am not mistaken?

hsulaimon

01-21-2014, 12:04 PM

Thanks again for helping Doug. It looks like it was a no go for the library. They have their reasons which I don't agree with but that's all she wrote. We'll try again next year.

JT A.

01-21-2014, 02:04 PM

I'll second Doug's comments. Currently the only untested tire we'd definitely want to test is the 7.5 inch wide Hoosier 10 (LC0 and/or R25B compounds). We like to have several tire designs in need of testing before planning another round.

Would you ever be open to the idea of testing the same tires but with a different test regimen to provide some dynamic data? Such as a frequency sweep of oscillating load at various slip angles to quantify how much tire load variation reduces grip, and collect tire spring & damping properties under dynamic conditions. I think some teams could make very good use of that data combined with a virtual 7 post rig model to select spring & damping rates.

DougMilliken

01-22-2014, 01:44 AM

Would you ever be open to the idea of testing the same tires but with a different test regimen to provide some dynamic data? ...
Historically, Calspan TIRF hasn't been able to run tests that require high frequency dynamic loading...the test head weighs something like 12,000 pounds (designed for heavy truck tires) and doesn't accelerate quickly up and down.

DougMilliken

11-14-2014, 02:59 PM

The FSAE TTC just passed 400 members (400 and 401 earlier today). Nice of FSAE.com to keep this big TTC thread sticky. A few thoughts:

+ Thanks to all the TTC contributors -- Calspan TIRF (show those logos!), tire companies, WSU for hosting our secure site, other industry supporters and volunteers...and of course all the member schools. The TTC has been far more successful than the founders ever imagined.

+ Not sure if your university is a member? Check the list (spreadsheet) at,
http://www.millikenresearch.com/fsaettcaccount.xls

+ If your school is a member, you can register for the forum with your university domain email at, http://sae.wsu.edu/ttc/
It might take a day or two to be approved.

+ Not sure of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on this page, http://www.millikenresearch.com/fsaettc.html
To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

+ Round 6 is tentatively scheduled for February 2015. Please post requests and suggestions to the secure forum--
‹ Tire Testing < Round 6 Pre-Test Discussion.

-- Doug Milliken for the TTC

DougMilliken

04-23-2015, 04:21 PM

This post is to announce TTC Round 6 testing:

+ Testing predicted to start on Wednesday afternoon May 6th at Calspan. End date could be Saturday May 9, or early the next week.

+ After gauging student interest, reviewing the tires currently used at Formula SAE/Student events and talking with the tire manufacturers (including some not represented below), we have chosen the following tire constructions:

1. The latest Continental 13" tire
2. Hoosier – 20.5 x 6.0 – 13 R25B A2500 (Item 43127)
3. Hoosier – 20.5 x 7.0 – 13 R25B A2500 (Item 43163)
4. Hoosier – 18.0 x 7.5 – 10 R25B (Item 43105)
* 5. Hoosier – 6.0 / 18.0 – 10 LCO (Item 41100)
* 6. Hoosier – 18.0 x 6.0 – 10 R25B (Item 43101)

Tires with a * were tested in Round 5 and will have limited retests performed on them, incorporating the new elements of the Round 6 tests.

+ As in previous rounds, all tires will be tested on two different rim widths. Rim widths will be similar to previous rounds.

+ Cornering (free-rolling) and drive/brake/combined tests will generally mimic Round 5. We have reduced the number of inclination angles to allow time for a few new tests.

+ New in Round 6 will be some relaxation length tests (transient tests) and some cornering tests at different roadway speeds. We are currently finalizing the test matrix with Calspan.

+ Data will be posted to the private forum when available. It usually takes a few weeks to receive all the data from Calspan and finalize all the supporting material.

+ TTC members are welcome to attend the tests in person. If you are interested, please contact Dr. Kasprzak. Calspan is located in Buffalo, New York, USA.

We will provide updates on the private forum as they become available.

As always, thanks to all that make the TTC possible.

I've started a new Round 6 topic, but also posting here in the "sticky" thread.

DougMilliken

09-17-2015, 06:36 AM

TTC Round 6 data has been posted on the TTC forum: sae.wsu.edu/ttc

You will need a TTC forum account to access the data. There are instructions for registering on the forum.

Also, the TTC public page has been updated with a list of the tires tested and other information:
http://www.millikenresearch.com/fsaettc.html

Thanks to everyone who contributed to Round 6!

[also posted to the Round 6 thread -- which is not sticky]

DougMilliken

03-18-2016, 03:36 PM

The FSAE TTC just reached 450 members. It's nice of FSAE.com to keep this big TTC thread sticky.

+ Thanks to all the TTC contributors -- Calspan TIRF (show those logos!), tire companies, WSU for hosting our secure site, other industry supporters and volunteers...and of course all the member schools.

+ Not sure if your university is a member? Check the list (spreadsheet) at,
http://www.millikenresearch.com/fsaettcaccount.xls

+ If your school is a member, you can register for the forum with your university-domain personal email at, http://sae.wsu.edu/ttc/
It might take a day or two to be approved.

+ Not sure of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on this page, http://www.millikenresearch.com/fsaettc.html
To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

-- Doug Milliken for the TTC

DougMilliken

05-26-2016, 01:35 PM

Round 7 tests were conducted in March 2016 and the data has now been posted for download by TTC members. Round 7 is a continuation of Round 6 and features four Avon constructions. The tests were funded by Cooper Tire & Rubber Company, parent company to Avon Tyres.

An updated list of all the tires that TTC has tested can be found on the public page,
http://www.millikenresearch.com/fsaettc.html

Thanks to all the TTC contributors -- now including Cooper Tire, as well as Calspan TIRF (show those logos!), tire companies, WSU for hosting our secure site, other industry supporters and volunteers...and of course all the member schools.

Thanks also to FSAE.com for keeping this big TTC thread sticky.

-- Doug Milliken for the TTC

DougMilliken

06-27-2016, 12:29 PM

The TTC forum has moved to our own domain, http://www.fsaettc.org We thank Washington State University for hosting the forum from 2009 through June 2016.

The move also included an upgrade to the latest version of phpBB, and the database was moved successfully. Please "Contact us" (bottom of any forum page) if you find a problem.

Some buttons you may remember from the home page are now on the "Quick links" pull down menu.

If you have links to pages on the original site, you will need to update the base portion of the URL.

-- Doug Milliken for the TTC

DougMilliken

10-29-2016, 09:37 AM

bump

In June 2016 the FSAE TTC private forum moved to http://www.fsaettc.org from http://sae.wsu.edu/ttc/ . The redirect link on the old site is now gone; we recommend updating browser bookmarks and other links. Thanks to Washington State University for hosting the TTC private forum for the last 7 years.

-- Doug Milliken for the TTC

mahmoudkassab

12-01-2016, 01:41 AM

I wannt tire data hoosier tire WET 21.0/6.5-13 for free because we havent enough money any help please ?

Pat Clarke

12-01-2016, 05:13 AM

Mamoud,

I have just issued you a first warning infraction.
I suggest you read and heed the accompanying message

Pat Clarke

BillCobb

12-01-2016, 08:11 AM

GoFund yourself !

JulianH

12-01-2016, 10:46 AM

And if you don't have money to pay for TTC, then tire data for a Wet tyre is the least of your problems...

mahmoudkassab

12-08-2016, 03:06 PM

I wanna know tire data Hoosier 20x7.5-13 R25A for free because i havent enough money to burchase it any help Please ?

MCoach

12-08-2016, 03:26 PM

I wanna know tire data Hoosier 20x7.5-13 R25A for free because i havent enough money to burchase it any help Please ?

Nice try...

Swiper, no swiping.
It costs less to register with the TTC than it costs to buy a single set of tires.

Pat Clarke

12-08-2016, 06:22 PM

Mahmoud Kassab,

Read your private messages!

Pat Clarke

Bemo

12-12-2016, 03:46 AM

I wanna know tire data Hoosier 20x7.5-13 R25A for free because i havent enough money to burchase it any help Please ?

I think the last year that tire was made was in 2009. Since then Hoosier only made R25B. Even if you find such a tire, I don't think it still matches the tire data.

Oh, and asking for illegal copies of the data in this forum is sort of ... special...

As others already mentioned. If you can afford Hossier tires, you should be able to just pay the fee for the TTC data.

DougMilliken

03-21-2017, 01:40 PM

Our friends at Calspan TIRF (where TTC testing is done) have a job opening in Buffalo, NY. Full description at this link:
http://calspan.catsone.com/careers/i...portalID=50135 (http://calspan.catsone.com/careers/index.php?m=portal&a=details&jobOrderID=9068364&portalID=50135)

Also posted in the Jobs section of FSAE.com

DougMilliken

09-20-2017, 10:11 PM

As of today, the FSAE Tire Test Consortium has 500 members worldwide. Nice of FSAE.com to keep this big TTC thread sticky. A few thoughts repeated from earlier milestones:

+ Thanks to all the TTC contributors -- Calspan TIRF (show those logos!), tire companies, other industry supporters and volunteers...and of course all the member schools. The TTC has been far more successful than the founders ever imagined.

+ Not sure if your university is a member? Check the list (spreadsheet) at,
http://www.millikenresearch.com/fsaettcaccount.xls

+ If your school is a member, you can register for the forum. Please use your university domain personal email at http://www.fsaettc.org It might take a few days to be approved. We are all volunteers, please be patient.

+ Not sure of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on this page, http://www.millikenresearch.com/fsaettc.html (http://www.millikenresearch.com/fsaettc.html)
To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

+ On the same public page, there is a list of all the tires that have been tested.

-- Doug Milliken for the TTC

Mohammad Saad

06-16-2018, 09:17 AM

Hey guys, this is Saad from Team Defianz Racing, Delhi Technological University, India. Our University has been a member of the TTC for the past 4 years now. However, since the past month, we have been unable
to access the TTC forums using our login credentials. Upon examination of the FAQs, I think we were de-registered from the forums due to inactivity. I have re-registered on the forums but have not yet been given
authorized access to the forums, although i received an e-mail informing me that our registration process has been initiated. I have e-mailed the board admin as well, but to no avail. I understand that the TTC
volunteers are busy people, so it is my plea to the board of administrators to authorize our access as soon as possible so that we may continue with our design( we are in our design phase and have encountered
a roadblock, and were looking for possible help on the TTC forums).

DougMilliken

06-16-2018, 01:48 PM

... I have re-registered on the forums ....
As a reminder, when registering for TTC, please use an email address from your university domain. TTC does not accept Gmail/Hotmail/etc. Also, we do not accept email addresses from any special domain that you have created for your team.

It should be your personal email -- something like this: student_name123@university_domain.edu

DougMilliken

07-05-2018, 10:00 AM

This post is to announce Round 8 testing:

+ Testing at Calspan TIRF is scheduled for Monday July 30th - Wednesday August 1st.

+ After gauging student interest, reviewing the tires currently used at Formula SAE/Student events and talking with the tire manufacturers (including some not represented below), the following tire constructions have been chosen:

Hoosier 43070, 16.0 x 6.0 - 10, R25B (free-rolling only, no drive/brake data)
Hoosier 43070, 16.0 x 6.0 - 10, LCO (free-rolling only, no drive/brake data)
Hoosier 43075, 16.0 x 7.5 - 10, R25B (free-rolling only, no drive/brake data)
Hoosier 43075, 16.0 x 7.5 - 10, LCO (free-rolling only, no drive/brake data)
Continental 43329, 205/470R-13 (free-rolling & drive/brake)
Goodyear 2704, 20.0X7.0 13 (free-rolling & drive/brake)

+ The test plan will be nearly identical to Rounds 6 & 7.

+ TTC members are welcome to attend the tests in person. If you are interested, please contact Dr. Kasprzak. Calspan is located in Buffalo, New York, USA.

+ Data will be posted to fsaettc.org (http://fsaettc.org) as soon as possible after the tests.

We will provide updates on the private forum as they become available.

As always, thanks to all that make the TTC possible.

I've started a new Round 8 topic, but also posting here in the "sticky" thread.

DougMilliken

11-30-2018, 06:23 PM

The FSAE Tire Test Consortium now has 550 members worldwide. Nice of FSAE.com to keep this big TTC thread sticky. A few thoughts repeated from earlier milestones:

+ Thanks to all the TTC contributors -- Calspan TIRF (show those logos!), tire companies, other industry supporters and volunteers...and of course all the member schools. The TTC has been far more successful than the founders ever imagined.

+ Not sure if your university is a member? Search the membership list (spreadsheet) at,
http://www.millikenresearch.com/fsaettcaccount.xls

+ If your school is a member, you can register for the secure forum. Please use your university domain personal email when registering at http://www.fsaettc.org (gmail, hotmail, etc or "team domain" email will not work). It might take a few days to be approved. We are all volunteers, please be patient.

+ Need a reminder of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on the public page, http://www.millikenresearch.com/fsaettc.html (http://www.millikenresearch.com/fsaettc.html)
To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

+ On the same public page, there is a list of all the tires that have been tested.

-- Doug Milliken for the TTC

DougMilliken

03-01-2019, 12:06 PM

The TTC forums are now up. When you register you need to use a university email address, this is used to verify TTC membership. I’m assuming that a lot of people will be registering in the coming week, so it may take me a while to approve your registration request.

The forum can be accessed at: http://sae.wsu.edu/ttc
A bit of history -- Brian's post above was from just over ten years ago, back on page 16 of this long thread -- 01-21-2009 01:45 PM. This started a long run of Washington State U successfully hosting the TTC. When WSU eventually retired their server, Brian handled the migration to our current home at http://www.fsaettc.org

In the course of searching for that old post, I scanned through many of the early posts in this thread. There is a lot of interesting information here, helpful for anyone getting started using laboratory tire data. A number of the people posting back then have gone on to successful careers in the motorsports industry.

That look back in history also reminded me that before the forum, TTC data was distributed by mail/post on DVD-R. As the membership grew, this started to become a real nuisance and we learned about the unreliability of postal mail to certain parts of the world...

As always, thanks to everyone that helps make TTC possible.

-- Doug Milliken

DougMilliken

03-21-2020, 01:41 PM

The FSAE Tire Test Consortium now has 600 members worldwide. While this FSAE.com site is short on contributors these days, it is still full of useful information--thanks to the site operators for keeping it open. A few thoughts repeated from earlier milestones:

+ Thanks to all the TTC contributors -- Calspan TIRF - download Calspan logos for your car direct from the source,
https://www.calspan.com/company/media-relations/, tire companies, other industry supporters and volunteers...and of course all the member schools. The TTC has been far more successful than the founders ever imagined.

+ Not sure if your university is a member? Search the membership list (spreadsheet) at,
http://www.millikenresearch.com/fsaettcaccount.xls

+ If your school is a member, you can register for the secure forum. Please use your university-domain personal email when registering at http://www.fsaettc.org (gmail, hotmail, etc or "team domain" email will not work). It might take a few days to be approved. We are all volunteers, please be patient.

+ Need a reminder of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on the public page, http://www.millikenresearch.com/fsaettc.html (http://www.millikenresearch.com/fsaettc.html)
To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

+ On the same public page, there is a list of all the tires that have been tested.

-- Doug Milliken for the TTC

DougMilliken

12-29-2021, 05:52 PM

This post is to announce Round 9 testing:

Round 9 at Calspan is scheduled for the week of January 17-22, 2022. We plan on testing the following tires, subject to availability (shipping, supply chain, etc.):

Goodyear 18 X 6.5 – 10
Goodyear 20.0 X 7.0 – 13 (Retest from Round 8)
Hoosier 16 x 6.0 – 10 R20
Hoosier 16 x 7.5 – 10 R20
Hoosier 18 x 6.0 – 10 R20
Hoosier 18 x 7.5 – 10 R20
Hoosier 20.5 x 7.0 – 13 R20
MRF 18 x 6.0 – 10 ZTD1

Some of these tires have already arrived at Calspan. All tires will be tested on two rim widths (yet to be finalized). We will use the test plan from previous rounds for ease of analysis and comparisons with older data. If time permits, we may perform a few one-off runs based on ideas posted in the TTC forums.

Unlike previous rounds, students are not permitted to attend the tests at Calspan due to the ongoing pandemic.

All data will be posted on fsaettc.org (http://fsaettc.org) a few weeks after testing concludes. We will send an e-mail indicating when it is available.

As always, thanks to all that make the TTC possible.

DougMilliken

02-08-2022, 05:03 PM

An email went out earlier today to everyone registered on the TTC secure site: We have posted the Round 9 FSAE TTC data on www.fsaettc.org (http://www.fsaettc.org/) under "Tire Testing / TTC Round 9". Please let us know if you have any comments or questions.

These tires were supplied by the tire sponsors and tested:

Goodyear D0571 18 X 6.5 – 10
Goodyear D2704 20.0 X 7.0 – 13 (Retest from Round 8)
Hoosier 43070 16 x 6.0 – 10 R20
Hoosier 43075 16 x 7.5 – 10 R20
Hoosier 43100 18 x 6.0 – 10 R20
Hoosier 43164 20.5 x 7.0 – 13 R20
MRF 18 x 6.0 – 10 ZTD1

Not sure if your school already joined the TTC in past years? Search (Ctrl-f) the spreadsheet found here:
https://www.millikenresearch.com/fsaettcaccount.xls

DougMilliken

04-26-2022, 02:54 PM

The FSAE Tire Test Consortium now has 650 members worldwide. While this FSAE.com site is short on contributors these days, it is still full of useful information--thanks to the site operators for keeping it open. A few thoughts repeated from earlier milestones:

+ Thanks to all the TTC contributors -- Calspan TIRF - download Calspan logos for your car direct from the source, https://www.calspan.com/company/media-relations/ , tire companies, other industry supporters and volunteers...and of course all the member schools. The TTC has been far more successful than the founders ever imagined.

+ Not sure if your university is a member? Search the membership list (spreadsheet) at, http://www.millikenresearch.com/fsaettcaccount.xls

+ If your school is a member, you can register for the secure forum. Please use your university-domain personal email when registering at http://www.fsaettc.org (gmail, hotmail, etc or "team domain" email will not work). It might take a few days to be approved. We are all volunteers, please be patient.

+ Need a reminder of the TTC license terms? Check the section named, "USE OF THE DATA – FSAE TTC LICENSE AGREEMENT" on the public page, http://www.millikenresearch.com/fsaettc.html To maintain our student discount at Calspan, it is important that there is no commercial use of the tire data or posting on the open internet. The TTC secure forum is the place to discuss the tire data in detail.

+ On the same public page, there is a list of all the tires that have been tested.

-- Doug Milliken for the TTC