Autonomous flight control for a Titan exploration aerobot

Robotic lighter-than-air vehicles, or aerobots, provide a strategic platform for the exploration of planets and moons with an atmosphere, such as Venus, Mars, Titan and the gas giants. Aerobots have modest power requirements, extended mission duration and long traverse capabilities. They can execute regional surveys, transport and deploy scientific instruments and in-situ laboratory facilities over vast distances, and also provide wide-area surface sampling. With the arrival of the Huygens probe at Saturn's moon Titan on January 14, 2005, there is considerable interest in a follow-on mission that would use a substantially autonomous aerobot to explore Titan's surface. In this paper, we discuss steps towards the development of an autonomy architecture, and concentrate on the autonomous flight control subsystem. Two research directions are described: first, the development of a highly accurate aerodynamic airship model and its validation; second, an initial implementation of the flight control system and the results obtained from autonomous flight tests conducted in the Mojave desert. We conclude by outlining further issues for research.