Modeling and Identification of Hover Flight Dynamics for NASA's Mars Helicopter

As part of the upcoming Mars 2020 rover mission, NASA is planning to include an autonomous helicopter to demonstrate the feasibility and utility of using helicopters for Mars exploration. Helicopter flight on Mars is challenging due to the extremely thin atmosphere, which is only partially offset by a reduction in gravity. This paper focuses on flight dynamics and controllability issues for the Mars Helicopter: in particular, the areas in which the dynamics differs from typical behavior on Earth. The paper discusses insights gained from modeling and simulation, as well as system identification performed with a test vehicle in the relevant atmospheric conditions, which culminated in the first demonstration of controlled helicopter flight in Martian atmospheric conditions in May 2016.