On Thursday the various pieces of my Ardupilot Mega (APM) arrived.  I decided that the APM was worth the expense.  At a minimum the APM will serve as a good practice for working with autonomous systems.  For the past two days I have been reading the manual, assembling, testing, and installing the autopilot on my aircraft.

In January 2010 I flew a few test flights with the original Ardupilot, however the autopilot was shelved due to a number of issues.  The most prominent issue was that the autopilot was designed with the ability to override the safety switch.  After efforts to find and cut the trace on the board that allowed this function failed the autopilot was not flown again.  Additional efforts to resolve this issue might have been made if the autopilot did not also suffer from poor performance.  The design of the APM fixes this problem allowing the safety pilot to take control at any time.

When purchasing the APM I decided that to avoid compatibility issues and to allow a fair evaluation of the system I would stick to using only components supported by the stock autopilot.  I am using the Mediatek GPS and have added the magnetometer and airspeed sensors to the APM.  I was a bit disappointed when I discovered that the magnetometer is not supported by the latest V1.0 APM software.

After the APM was bench-tested I took it outside for a series of telemetry gathering experiments.  So far I’ve conducted three flights to verify the safety switch and telemetry acquisition functions of the APM.  Unfortunately I have been unable to collect telemetry data in-air.  This may be due in part to my inexperience with the system or some other unknown issue.  To address this I’m working on a set of flight checklists and will be adding radio modems to the system.  This will allow the status of the system to be more easily assessed.

I am looking forward to working with the APM over this winter break and hope to achieve autonomous flight very shortly.  Almost more importantly, I plan to release test data benchmarking the APM against the Piccolo Autopilot.