GPS Rolling Resistance Calculator

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Rolling resistance may be calculated using only a GPS and some hills.

rate of change of kinetic energy + rate of change of gravitational potential energy = power lost due to resistance

This assumes that the engine is in neutral and includes both aerodynamic, tyre and transmission-in-neutral losses.

This GPS provides height and velocity at 1 second intervals. From this and the weight of the vehicle, the rate of change in kinetic and gravitational potential energy may be calculated.

I wrote a program to perform the calculations and plot graphs. If you want a copy of this program (and sourcecode) please get in touch. I'll prepare it for release shortly (and sooner if someone asks).

gpsbabel -i nmea -f src/main/gps/YellowMiniHarbourBridgePasses.txt -o gpx -F - | \
java -classpath /home/tparker/.m2/repository/jfree/jfreechart/1.0.3/jfreechart-1.0.3.jar:\
/home/tparker/workspace/RollingResistance/target/classes org.carrott.RollingResistance \
830 -100 0.5 100 -100 Yellow

-- Main.TomParker - 22 Jun 2007