First year cars

[Igor]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Can a first year team win FSAE outright?
EASILY! </div></BLOCKQUOTE>

You're a funny guy, will you be doing stand-up-comedy at the Detroit competition? We all like a good laugh. Maybe you could bring some uneducated farm boys with you to give a design seminar.

Igor

[clausen]

We'll it's not quite the same, but our team from last year were all new to the competition, and had almost zero input from the team before, so beside having a car to drive a bit (while we could keep it going) we were for all intents and purposes a first year team. I was totally confident we could win up until the last month when we were getting very little testing done. We did end up winning design and getting 2nd in skidpan.

I think it's totally do-able for a first year team to be competitive. You just need to get your shit together a bit better than we did

[IsheeM]

Paul,
From your arguement, it does seem as though you guys were nearly a first year team. However, there are some big differences between your team last year and a true first year team. A true first year team may have to convince the school of the project's benefits, establish access to machining equipment, establish some type of team structure, figure out how to begin to recruit members and money, get the software and hardware necessary to design and test this stuff, etc. This is what I believe a lot of people forget about when discussing first year teams. The above mentioned items in themselves is quite a large amount of work. I dont think there is anyway a true first year team could compete of overall wins or even design wins. That is just speaking from my prespective though.

[Denny Trimble]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Z:
Can a first year team win FSAE outright?

EASILY! </div></BLOCKQUOTE>

A few second-year teams have won outright. Wollongong placed 28th in the US in 2002, then won in 2003. Texas A&M placed 14th in '99 and won in 2000.

There's a lot to learn, and a lot of infrastructure to build, in a team's first year. It's not impossible for a first year team to win, but you're going a bit far to say it's easy.

[Urvina]

so how about...maybe...fifth?

we want to put our state on the map. even though its the biggest state in the country, we go unnoticed way too much. so im thinkin we want to be in the top five. possible?

hell yeah

[MikeWaggoner at UW]

If a first year team wants to be successful, they'll need to know how to answer questions, and what level the design boards etc. should be at, and generally what to expect. I bet some teams would let a stranger ride along...

[Z]

Erin,

The post office often advertise that their goal is "to deliver 90% of all mail within 24 hours". So, if they've delivered the 90% at 10am, do they put the other 10% on a shelf to age for a week or so? That's their stated goal.

If you've found a loophole in the rules that, according to your simulations, allows you to build a car 10% faster than any previous FSAE car (from their listed times), do you throw that design in the bin?

If you want to come first, then that's what you should aim for. In fact, aiming for 20% faster will give you some leeway...

Z

[James Waltman]

Erin,
They already put your state on the map – down there by Hawaii.


I bet your team has plenty of CVT knowledge to pull one off. Just make sure you weigh the tradeoffs. A turbo is not beyond a first year team. I suggest that you get the car running without one first though. Then when you have spare time you can add the turbo.
Aim high.

Have you worked out a way to get to Detroit next month?

[Z]

(...continuation of "EASILY" post)

How does a first year team determine what is most important for a fast FSAE car?

Here is one possible way to find out.

Do a lap time simulation of different types of cars on typical FSAE Autocross and Endurance tracks. You can download a simulator (somewhere?) or just DIY. Initially, only a very simple simulation is required. Later you can add more detail.

Start with a simplified track map that consists of constant radius corners connected by short straights. The track has no width so all cars follow the same line. Driving style is "classic", ie. straight-line acceleration and braking, and constant speed cornering. This makes the maths very simple. Later you can add track and car width, adopt a "blended cornering" driving style, and manually drive the car like a video game.


Initially, the car is simplified to a "mathematical point" with the following attributes:

Mass (100kg - 500?kg) - This is car + driver mass. Yes, start at 100kg to find out if low weight really is important.

Power (10kw - 70kw) - Effects high speed acceleration and top speed.

Coefficient-of-Friction (Cf-max = 0.1 - 2.0) - Maximum possible tyre grip effects horizontal accelerations.

Aero-Drag (Cx.A = 0.1m^2 - 2.0m^2) - Effects acceleration, braking, and top speed.

Aero-Downforce (Cz.A = 0 - 10m^2) - Effects horizontal accelerations.

It is useful to display the track map on the screen and have multiple different coloured dots representing different cars racing each other around the track. This makes it obvious where on track some cars have an advantage, and by how much. Choosing a high and low number for each of the above parameters gives 32 cars to test, for a start.


The above should make obvious which of the parameters are most important. But it still doesn't give much detail of the car. The next step is to split Cf into three.

Cf-Acceleration - Less than Cf-max for cars with 2WD.

Cf-Braking - About equal to Cf-max, unless you've got really bad brakes.

Cf-Cornering - Less than Cf-max to account for a badly set-up or difficult to drive car.

More screen testing, and now you should have a good idea what makes a car fast IN FSAE CONDITIONS. Perhaps more importantly, you should also know where NOT to spend time and money.


Of course, the better established teams will have done this, in much more detail, every year that they've been in the competition.

So, any hints as to the results, guys? (Denny, anyone else...?)


Z

[Kevin Hayward]

Z,

I know I end up putting hints to results of sims in responses to forum questions. As I would guess others are doing on this forum.

We as a team end up putting even bigger hints into how we build our cars ... and what we look for. We started out building a car that was similar spec to a 'standard' fsae car. We have made changes over the years. So if you want to know what results our sims and testing are giving us then have a look at the direction of change in our cars.

Unfortunately I think that most teams probably have their 'future development' projects fairly well under wraps. I know that we do. It is those projects that really indicate where we are going with the whole deal.

But if I was to say one thing don't overestimate the importance of weight savings. Yes car-to-car with equivalent systems it is still pretty much number 1. However there are quite a few examples where a few hundred grams added can find more vehicle speed than the performance lost due to weight gain. I mention this because if there is a common theme amongst these forums that losing weight wherever and whenever possible is the solution to all the performance issues. It just isn't true ... well at least it isn't the whole truth.

...

What the first year teams do not have is the data from previous cars to make informed decisions. To make situations worse for the newcomers is that this problem gets worse as the years pass by. Decisions get better and better as data accumulates and is analysed. Furthermore if simulations shouldn't be trusted too much until they have been benchmarked against vehicle testing.

Cheers,

Kev