ARMONIA: Feasibility Study on Aerobots in Martian Atmosphere to Enhance Science Return

In the framework of a prolonged Mars exploration, a mission to Mars supported by aerial vehicles has been investigated. The study exploits aerial platforms to collect high resolution ground and atmosphere data flying on extended Mars regions for prolonged period. The polar and tropical regions are to be visited: The former to collect data on the sublimation of polar caps during spring and detect source of methane, the latter to deepen the knowledge about the genesis of local dust storms, the formation of dust devils, enhance knowledge on Hellas Planitia and Valles Marineris. The Armonia Mission architecture includes 1 orbiter, 2 ground sensors stations delivered in the tropical regions, and 3 balloons, to fly over the pole and monitor the icy caps seasonal dynamics, and over the tropics investigating storms formations and winds evolution. The paper briefly introduces the whole mission and subsystem sizing, and focuses its attention on the balloons technology: The Mars Climate Database has been exploited to model the seasonal evolution of the atmospheric temperature, density, wind velocities, fundamental properties to tune the balloons design. Super- pressure balloons have been selected as better suited for the Mars application; the performed design, her presented, highlights the strong interdependences among material selection, environment, path planning and GNC, operations, for those aerial vehicles. The balloons (28m and 35m in diameter respectively for polar and tropical areas) are filled with helium and can fly a gondola of 42kg, connected to the balloon thanks to a 500m tether. The design compliance with respect to the mission and performance requirements is discussed too together with the technology readiness to run the mission.