On TV, when we see the throttle/brake meters, as well as the speed and RPM of the car, is it all based on sounds only? I find that a bit tough to swallow as sometimes you even saw what gear the car was in (even way back in the 90s) and I don't know how you can get all this data just from sound?

Thanks for any clear explanations.

It's possible TV is allowed a sensor to determine the amount of force applied to the brakes, but I believe RPM is determined by volume.

Gotta keep out that traction control.

Yea, that makes sense. What about the gear changes, and speed?

Sandeep_Banerje - 07 August 2009 09:43 PM

Yea, that makes sense. What about the gear changes, and speed?

there is a telemetry box (also contains camera equipement on the roof of the car (round disc looking box on forward part of roof near windshield.) GPS (location and speed) telemetry transmission device (radio transmission of the data) and a recording device for a few sensors on the car. Engine Rpm, Throttle position, G meter.
It's unclear whether they allow a wheel speed sensor, to allow for a gear change graph (difference between RPM and wheel speed to show gear changes) Suppose it could be calculated by GPS speed and rpm, but not as accurately.
Braking would registrar on the long G meter, as does acceleration G's
None of this data is allowed to accessed by the teams, and is solely for the TV station and Nascar uses..
The system is supplied by Sportvision, mainly for the graphics you see on TV.

I wouldn't think we could actually get accurate brake and throttle graphics without having a tps and bps sensor on the pedals. When in the draft it's holding the same rpm and speed down the straight but we see the graphics showing guys feathering the throttle and just barely dragging the brakes at times as well. I don't think it would be a big deal to stick a potentiometer on the gas and brake, run the quick calibration for the travel each driver likes, and run one of the RPM outputs from the ignition boxes straight to the data box.

stowaway - 09 August 2009 01:04 PM

I wouldn't think we could actually get accurate brake and throttle graphics without having a tps and bps sensor on the pedals. When in the draft it's holding the same rpm and speed down the straight but we see the graphics showing guys feathering the throttle and just barely dragging the brakes at times as well. I don't think it would be a big deal to stick a potentiometer on the gas and brake, run the quick calibration for the travel each driver likes, and run one of the RPM outputs from the ignition boxes straight to the data box.

The throttle is a tps sensors. A long G sensors is highly accurate, and is infact used on racing data systems for braking performance. Really the only difference between G's and brake pressure is that G's will show a lift and no brake, where BPS will show only brake pressure..
As far as the sounds not matching the display, there is a delay from sending/recieving/display information as the data transits from the car to your tv screen.
Even the high dollar live telemetry systems used in racing has a delay, sent directly from the car. It's "live" but not exactly...