[danimal]

Yes, I do sit around thinking about stuff like this

A Flat Tire Monitor (FTM) uses the ABS sensors to determine if one wheel is spinning at a different rate than the others.

A Tire Pressure Monitoring System (TPMS) measures the pressure of each tire individually using a valve sensor in each wheel.

The FTM is simpler and doesn't require any extra hardware, but it can only warn the driver if one tire is flat, not if all four tires are low on air.

The TPMS can warn you if you have a flat or all four tires are low, but the costly valve sensors can be easily damaged by unknowing tire installers or if you attempt to use a can of Fix-A-Flat.

My idea: Combine an FTM with a GPS receiver, and you get all the benefits of TPMS with less complication and cost. The software simply needs to compare wheel RPMs with the GPS calculated speed of the car. If these numbers ever get out of whack, warn the driver. Simple.

-Dan

[kRUNCHe90]

Wouldnt that give you the same result?

[danimal]

Originally Posted by kRUNCHe90

Wouldnt that give you the same result?

Hopefully not

When you reset the system with all your tires properly inflated, they will have a particular diameter and will spin a certain number of times at a given speed. If they lose air over time (or the weather gets colder), their diameters will shrink slightly, and they will spin at a slightly faster rate for a given vehicle speed.

-Dan