Track Mapping

[IsheeM]

I am interested in the track mapping capabilities of the Motec system. Does the beacon assembly, necessary for track mapping, relay the course's elevation change?

Thanks,

[Denny Trimble]

Nope. It's a very simple system. The sensors needed are:
Wheel Speed
Lateral G's
Lap Beacon (to tell start/end of lap).

You can think of it as "inertial navigation".

In '99 I added a few columns to somebody's endurance data spreadsheet and came up with a course map the same way.

If you know lap distance, speed, and lateral g's, then the process is:

For each lap distance increment:
-Calculate radius of curvature of vehicle path from A = V^2 / R (R = V^2/Ay)
-Calculate the heading change for that radius over the lap distance increment
-Plot your new position and continue

This system doesn't do well with cambered corners, though.

[Nick McNaughton]

You don't even need a beacon to do it - you can slot in lap markers during post processing in Intepreter, and it'll work it all out for you. Pick something like a minimum speed point for a hairpin, or a top speed point on a straight that's at about the same place every lap and it'll get you to within a tenth or so...