For the most up to date information, visit the UAVDevBoard website.
A new approach for turn controls that produces tight, stable, smooth, coordinated turns both in normal and inverted flight has been developed and flight tested. The math basis for the controls is described here:
Implementation details and results of flight testing of helical turn controls will be posted here soon.
The following are links to important legacy postings regarding algorithmic innovations that have been incorporated into the MatrixPilot autopilot and in most instances, also adopted into ArduPlane and ArduCopter.
[Note: some of the links in the postings below have gone stale. Here is a link to all ot the MatrixPilot documents, including the documents referred to by the links.]