Digital Autopilots For Rotary Winged Unmanned Aerial Vehicles

Traditionally analog systems have been designed for use in rotary winged vehicle stability augmentation systems. Many manned helicopters currently have autopilot systems which reduce pilot work load and maintain stability, but are of limited authority. Future rotary winged unmanned aerial vehicles, however, will require a high degree (or in some cases total) authority over the platform. Digital implementations will be required to adequately replace the piloting function (inner loop control) and the navigator function (outer loop control) in the absence of a human pilot. This paper describes the requirements of an autopilot system geared for unmanned rotary winged applications, and enumerates the advantages of a digital implementation from an electrical, physical, and functional standpoint.