Is simulation really required ?

[Damped]

Hello everybody !
I am from India so 'cash stripped' is naturally tagged with our team...
I want to ask that are simulations for suspension designs really required ? because we really cant afford such softwares.
I am done away with weight transfer and other intricacies, will it be sufficient for the first time to design by intuition ?

[Damped]

Hello everybody !
I am from India so 'cash stripped' is naturally tagged with our team...
I want to ask that are simulations for suspension designs really required ? because we really cant afford such softwares.
I am done away with weight transfer and other intricacies, will it be sufficient for the first time to design by intuition ?

[FATMOUSE]

If you do the calculations required, you can get a pretty decent design going, but simulation will help you see more details (intricacies of alignment changes on deflecting, load transfer, that you just need a computer to do the heavy lifting on).

So if you can get it, do so. Susprog3D is decent, and not too expensive (used it last year).

[Damped]

Thanks buddy, but even this much 250-300$ are not feasible to spend on software. Solidworks and other were provided by the college as they already had them but this much..we cannot buy at any cost...
Can I go on without softwares ?

[A Richards]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Damped:
Thanks buddy, but even this much 250-300$ are not feasible to spend on software. Solidworks and other were provided by the college as they already had them but this much..we cannot buy at any cost...
Can I go on without softwares ? </div></BLOCKQUOTE>


I'm pretty sure that people have managed to build race cars before computers were around. I'm sure that you can to.

[Wesley]

Simulation software is just another tool in the engineers bag - it just makes the numbers easier to crunch. The equations the computer does can still mostly be done by hand, just slower.

You can get along just fine without it, it just gives you that competitive edge.

[gyanu]

ABE GAREEB......KHARRED LE ....ZAROORAT PAREGI......DO DIN BHOOKE REH JA........

[Damped]

@gyanu
people like you are too much, this is a forum and, a public one a bit of reserved nature will keep you in good books....
but this type of behaviour is ingrained in people like you....

Sorry people for this deviation...


Sincere thanks for your suggestions..

[exFSAE]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by gyanu:
ABE GAREEB......KHARRED LE ....ZAROORAT PAREGI......DO DIN BHOOKE REH JA........ </div></BLOCKQUOTE>

Pierogi?

[Superfast Matt McCoy]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Damped:
Thanks buddy, but even this much 250-300$ are not feasible to spend on software. Solidworks and other were provided by the college as they already had them but this much..we cannot buy at any cost...
Can I go on without softwares ? </div></BLOCKQUOTE>

Solidworks has motion simulation that should be pretty helpful in measuring suspension dynamics. You could be clever with creating planes and axes and get good information that could make development a lot easier.

[FATMOUSE]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by exFSAE:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by gyanu:
ABE GAREEB......KHARRED LE ....ZAROORAT PAREGI......DO DIN BHOOKE REH JA........ </div></BLOCKQUOTE>

Pierogi? </div></BLOCKQUOTE>

Basically, he is calling the original poster poor, asking him to buy the software, it'll definitely be needed, stay hungry for 2 days if you have to.

Not very pleasant.

[Composites Guy]

I suggest that Solidworks (with its motion simulation), Microsoft Excel (for spreadsheets), and a little ingenuity is all that you need to make a very fine simulation of your own. Sure there may be better simulation software availiable that can calculate every nuance of an F1 car... but do you think these tools are fully and acurately exploited by undergraduate students???

I would not spend ANY money on software for your car design... given that you have free Solidworks. Focus your money where it will be of best use.

mmmmmm.... perogi's....mmmmmmm

[HenningO]

Surprisingly nobody has yet mentioned the use of real-life models. Caroll Smith mentioned this many times in his books.

Basically, build a (scale) 2D model of the suspension using cardboard. Make the hardpoints adjustable and use a ruler/caliper and see what happens when the wheels moves. Even if you don't use this for your final design, it'll help you grasp the concept much quicker and will give you a goods starting point for further computer analysis.

But I also agree with previous posts, using Solidworks (with or without Excel) will get you quite far. I believe there are some webcasts/online seminars how to set up a FSAE suspension anaylsis on the Solidworks website.

[DART-CG]

Composites Guy is right: Whatever you use for you design, (wheter Solidworks or NX5) you have a motion tool implemented in it. And Excel will do fine, too http://fsae.com/groupee_common/emoticons/icon_smile.gif

Check out your university, perhaps they have some licenses. And don't tell me that you don't know anybody who will "provide" you with different sorts of software!

[Anvit Garg]

Claude said if you can crack his software he will provide free copies...

[FATMOUSE]

^No problem, just send me the source tarballs :P

[VFR750R]

The best engineering tools are the ones you make yourself. You learn alot creating the tool about how your system works. You know with intimacy all the variables and details involved, and don't need to interpret a user manual or help index.

Car simulations seem to require less input to get solid output compared to engine sims, but you can get 90% of what a sim will get you with excel doing hand calculations. The last 10% relies on the tires... which means...good luck with or without a sim.

And remember, there is NO replacement for physical testing when at all possible. Sims just narrow the range of things to test.

[PSUAlum06]

full blown K&C packages are great, but if you're looking for basic kinematic analysis, solidworks and excel would be plenty.

it's also worth pointing out that you can do a lot with a student license of matlab/simulink. If you wanted to do some vehicle modeling it wouldn't be impossible to put a nice model together in matlab and then run an optimization.

[Dennis Seichter]

If you have access to Matlab/Simulink, try building your own suspension simulation with Sim/Mechanics.

And, as a lot of people mentioned before, for all the static stuff excel will do just fine.

[DART-CG]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Anvit Garg:
Claude said if you can crack his software he will provide free copies... </div></BLOCKQUOTE>


Uuuh, tough statement from Claude http://fsae.com/groupee_common/emoticons/icon_smile.gif
Perhaps he first should have taken a look on appropriate websites before stating that. As I heard the crack already exists...
Jippie! Free copies for all of us! http://fsae.com/groupee_common/emoticons/icon_wink.gif

[alpha754293]

If you know the equations, I'm sure that you can use even a simple spreadsheet to help with the number crunching.

More advanced versions of that, but with very little or no money is to program it using something like FORTRAN to help do the iterative designs faster.

Otherwise, you'd be working with programs like MATLAB, MathCAD, or Maple to do the same thing.

Sometimes, companies would give you licenses to use the software for free or very little money if you're with a school because they want to promote you guys using it.

Otherwise, the last alternative would be the tried and tested -- pencil and paper. (And a calculator).

[Nitesh]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by gyanu:
ABE GAREEB......KHARRED LE ....ZAROORAT PAREGI......DO DIN BHOOKE REH JA........ </div></BLOCKQUOTE>

Buddy, what or who do you think you are?? you come here on this forum and start balsting away at people involved in serious and meaningful discussion and that too in Hindi, a language not common amongst the members of this forum. This is a respectable forum used by people internationaly and not your local mushrooming blog where you could blast away with any appropriate/inappropriate comments..

You are not only ruining it for yourself but for a lot of other students from India who are serious about this stuff and not about your 'wipe your dirty ass here' kinda humour. Please refrain from such posts on this forum.

[MarkoFSBR]

hello everyone,

you don't need some fancy software to get the car rolling .

you have access to solidworks ? great

draw 2 simple 2d sketch's that are not fully constrained of your suspension from the front view and top view and you can do a decent geometry on roll and bump ,even combined motion...

as you move the unconstrained sketch it will see how your suspension will move.
you cant get simpler than that

[John Grego]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by MarkoFSBR:
hello everyone,

you don't need some fancy software to get the car rolling .

you have access to solidworks ? great

draw 2 simple 2d sketch's that are not fully constrained of your suspension from the front view and top view and you can do a decent geometry on roll and bump ,even combined motion...

as you move the unconstrained sketch it will see how your suspension will move.
you cant get simpler than that </div></BLOCKQUOTE>

This is a good way for all teams to check their suspension software. 3-D models that include rod ends and celvises can easly move differently than the point to point models used by software. We build the suspension in SolidWorks and then put it through its entire range of motion to check motion ratio, camber gain, wheel travel, clearances, VSALs, etc.

[BillCobb]

The simple answer is YES. The complete answer is "Yes, if you dare to model the complete system which includes correct geometry, flexible elements, tire properties and powertrain loads."

If you have ever wondered why some race teams do well "right off the hauler", then you will now know the reason why. If you ever wondered why some teams have extra confidence about their design and have the answers to the judges questions, then you will learn why. If you ever wondered why some team's cars have more holes in the chassis for adjustments than metal area, or if you ever wondered why some teams need a trailer full of springs, bars, wheels and tires, while others need only a spare set, then you will now know the reason.

It has to be a good simulation, too. Leave out the complex parts or effects or relationships, its only gonna hit a single. Do it right and its a home run. And it can then be done race after race, year after year. Most racing now is a simulation contest, not a "change parts and drive around doing laptimes" event. A good simulation tells you why, not just if or how.

It ought to help you eliminate 95% of the trials that should never be considered for build, leaving the time and money to try things that some told you would never work.

The driver/crew chief or team owner no longer calls the plays in real world racing. The sponsor does. The sponsor wants results. Anybody who wants to dispute that should also bring along some credentials, not an academic opinion. A proper balance of the triad of practise, laboratory testing and simulation is the real world for the industry. The sooner you start, the more likely you will be noticed by the companies now looking for "new school" racing methodology. "old School" is .... "old".

[Alan]

People keep mentioning Solidworks and Excel together without explicitly mentioning the API (although I think this is what people are alluding to). By using the API you can "control" Solidworks through VBA code, effectively giving you what you need to make your own simple kinematics software.

Bill, its always great to read your posts. People of your experience/understanding (especially concerning tires) make this forum fun to read. I think your answer is perfectly valid if asked by a professional race team. Clearly the organization Damped is from is not there yet. It doesn't mean that they don't aspire to be. But sometimes you gotta focus on more fundamental things (like getting a car built in the first place).

[carbon_black]

Indeed, the API is fantastic. A couple of quick sketches with smart dimensions, a few lines of code and you can cycle your suspension through its full arc and measure whatever you so desire.

It's a very powerful tool, and the resources at http://www.solidworks.com/pages/services/APIDownloads.html are invaluable.