i wanted to create a telemetry platform using the arduino for a car that a bunch of us are making. the link http://www.practicalarduino.com/projects/vehicle-telemetry-platform ...has the code but it requires the car to have an inbuilt management system.
Since we are constructing the car from scratch we don't want to have an ECU ...can i still plot the speed of the car at different coordinates as shown on that site with a GPS module and 2 speed sensors and the arduino ???
Basically, just set a time-interval at which to sample your location coordinates. After the set time has elapsed, log the location and the time it was logged (location and time will be in the gps NMEA sentence.) Then when the next one is logged, you calculate the distance traveled between the two locations and the elapsed time it took to travel between them to find the average speed between those two locations.