Ok, i want to get this formulae into excel:

v=((u.R)²/((m/r)²+(1/2p.A.Cd)²))^1/4

I know the basics of coding stuff like that into excel, but when i do this formulae, i think the results are wrong. It gave me 95mph for a corner with 200m of radius.


Here's the data i used to experiment the code:

mass(kg) 1400
Frontal area(m²) 1,3
Cd 1,4
Tyre Fricction(u) 1,4
Air Density(p) 1,23
Corner Radius 200m
Gravity 9,8

Downforce/Lift is being ignored so far.

Am i doing this wrong?

Quote from Bumpdrafter :

Am i doing this wrong?

Erm, yeah.. you need to upload those images somewhere or attach them to your post so we can see them..

As for the Excel question I'm too tired to even consider thinking about it, sorry.. Good luck and good night

Oops, i dont remember posting a photo O_o

Oh well, i'll edit it.

Maybe brackets around the "1/4"? Either way I couldn't come up with 95mph. Also there doesn't seem to be any gravity in your formula. What are you trying to calculate anyway? Drag force doesn't contribute to cornering force.

Its because the formulae has embedded in itself the Aero Drag formulae, the Centripetal Force formulae and the Limiting Friction formulae. Gravity is there, kind of. R is the normal force (m.g).

And later i'll add downforce to the calculations.

I'm looking at that formula and I can't work out what it's supposed to do.

Also, if you're working in SI units, then speed will be in m/s, not mph.

http://www.jameshakewill.com/Lap_Time_Simulation.pdf

Here's the paper that describes the simulator i'm trying to reproduce. I'm probably fookin things up somewhere, but i don't know where.

Quote from Bob Smith :

Also, if you're working in SI units, then speed will be in m/s, not mph.

!

I knew i was fooking up somewhere. but i don't think that solves my problem though

Quote from Bumpdrafter :

Gravity is there, kind of. R is the normal force (m.g).

Ok. Then the brackets around the 1/4 and the unit conversion are the problems.

The formula seems to be based on the idea that at your max cornering speed you will be on the throttle just enough to stop the drag from slowing you down. Not sure how useful that approach is for race track simulation. Ok I guess for a simulation that brakes and accelerates in a straight line, but not very close to real life. I think Brian Beckman had some simple calculations in his Physics of Racing series that also consider accelerating and steering wheel unwinding.

Quote from Bumpdrafter :

http://www.jameshakewill.com/Lap_Time_Simulation.pdf

Here's the paper that describes the simulator i'm trying to reproduce. I'm probably fookin things up somewhere, but i don't know where.



!

I knew i was fooking up somewhere. but i don't think that solves my problem though

well, m/s * 3.6 = km/h. so... 342 km/h. What kind of super car do you magically have?!

Quote from J.B. :

Ok. Then the brackets around the 1/4 and the unit conversion are the problems.

The formula seems to be based on the idea that at your max cornering speed you will be on the throttle just enough to stop the drag from slowing you down. Not sure how useful that approach is for race track simulation. Ok I guess for a simulation that brakes and accelerates in a straight line, but not very close to real life. I think Brian Beckman had some simple calculations in his Physics of Racing series that also consider accelerating and steering wheel unwinding.

Yes that's the problem of this model, it features a super-godlike race driver that is able to perfectly judge how much grip is avaliable and tackles corners at max speed. I think its possible to make the driver a little bit slower and/or inconsistent by playing a little bit with percentages.