Autopilot Abstraction and Standardization for Seamless Integration of Unmanned Aircraft System Applications

Nowadays many autopilot manufacturers are available in the commercial market for fixed wing small/mini Unmanned Aircraft System. Several autopilot configurations exist with a wide variety of selected sensors, sizes, control algorithms, and operational capabilities. However, selecting the right autopilot to be integrated in a given Unmanned Aircraft System is a complex task because none of them are mutually compatible. Moving from one autopilot to another may imply redesigning from scratch all the remaining avionics in the Unmanned Aircraft System. This paper presents the Virtual Autopilot System to facilitate exploitation of data obtained from the autopilot to be used by other applications on board. At the same time, it provides a hardware-independent interface that isolates payload and mission components from the autopilot specificities, thus eliminating dependencies on a particular autopilot solution. This subsystem is integrated into an Unmanned Aircraft System mission-oriented architecture called Unmanned Aircraft System Service Abstraction Layer, which promotes the development of automated concepts of operation keeping the Unmanned Aircraft System pilot fully under control. The VAS and its surrounding architecture have been implemented for a variety of autopilots, ranging from the commercial AP04 from UAV NAVIGATION, to the Paparazzi autopilot and even autopilots for ground-based vehicles. In all cases the selected Virtual Autopilot System interface was maintained, overall capabilities increased due to the flight-plan and mission-oriented perspective offered by the surrounding architecture, and development times exponentially reduced as the Virtual Autopilot System design is consolidated. This wealth of experimentation demonstrates that employing a standardized interface facilitates the integration of new Auto Pilots, but at the same time capabilities are not only maintained but dramatically increased by developing flight-management systems on top of the Virtual Autopilot System standard interface.