Units of twistiness

OMX

May 2010
2
0
Alicante, Spain
I want to compare race tracks by analysing how twisty they are.

This is interesting because some race bikes in the TTXGP races go fast in a straight line but have to go round corners quite slowly while others go slower in a straight line but corner better.

I am trying to think up a simple way to describe the twistiness of the track (in 2D is fine for the moment).

For example is there a standard way I can compare:
File:Road America.svg - Wikipedia, the free encyclopedia
with
File:Infineon (Sears Point) with emphasis on Long track.svg - Wikipedia, the free encyclopedia
and
File:Monte Carlo Formula 1 track map.svg - Wikipedia, the free encyclopedia

Ideas, suggestions?

OMX
 

OMX

May 2010
2
0
Alicante, Spain
Would simply counting the number of bends tell you how twisty the course was?
Road America: 11
Infineon: 14
Monaco: 13
Indianapolis Speedrome: 4

Problems:
1) What counts as a "bend" can be difficult to decide. For example "Beau Rivage" (#2 at Monaco) or corner #4 at Road America don't look like corners. They are just slight variations on a straight. The angle and the length of the corner should also count towards the twistiness index.

2) Monaco [1] looks much more than three-times more "twisty" than Indianapolis [2]. A circle isn't really twisty at all.

3) Monaco seems more twisty than Infineon because while there are a similar number of corners Monaco is a shorter track (Monaco = 3.340Km, Infineon = 4.05km). Should we calculate a ratio of corners to track length?


[1]File:Monte Carlo Formula 1 track map.svg
[2]File:Indianapolis Motor Speedway - Speedway.svg - Wikipedia, the free encyclopedia
 

Bruno J.

MHF Hall of Honor
Jun 2009
1,266
498
Canada
You might want to calculate the curvature at each point, and then calculate the average curvature with respect to arc length. You'd need to have a good understanding of calculus to do this!