Instructions for using ArduPilot 2.x in the field: ArduPilot 2.1 and above (with Z sensor). This version of the software auto-calibrates the IR sensors. The only thing you need to do at the field is to record the "home" GPS position in EEPROM memory, which will not be erased when you reset or power down the board. To do so, follow these instructions: Ensure that the autopilot is in manual mod…