I finally managed to get my hands on the em-408 GPS receiver. After making provision on the autopilot board for the sensor and making sure that the OpenLog board could save the data, it was time to put this baby to its paces. It was no small feat I must add although the "old faithful" internet  was right there besides me to give me along. I found that there aren't many scripts that give an modular solution to allocating GPS data to variables in Arduino for further processing. So I made my own :). My approach was not to disrupt the internal timers of chip due to servo control. So the GPS board communicated with the rest of the system through the hardware Serial channels. This also enabled the processing of the data coming in prior to it being used in the rest of the system. So the aim of the board is to give heading coordinates to heading tracker function which in turn controls the roll and pitch controller. My plan is to use the haversine formula to calculate th...