Hybrid Autonomy Framework for a Future Mars Science Helicopter

-- Autonomous aerial vehicles, such as NASA's Ingenuity, enable rapid planetary surface exploration beyond the reach of ground-based robots. Thus, NASA is studying a Mars Science Helicopter (MSH), an advanced concept capable of performing long-range science missions and autonomously navigating challenging Martian terrain. Given significant Earth-Mars communication delays and mission complexity, an advanced autonomy framework is required to ensure safe and efficient operation by continuously adapting behavior based on mission objectives and real-time conditions, without human intervention. This study presents a deterministic high-level control framework for aerial exploration, integrating a Finite State Machine (FSM) with Behavior Trees (BTs) to achieve a scalable, robust, and computationally efficient autonomy solution for critical scenarios like deep space exploration. In this paper we outline key capabilities of a possible MSH and detail the FSM-BT hybrid autonomy framework which orchestrates them to achieve the desired objectives. These inputs trigger state transitions or dynamically adjust behavior execution, enabling reactive and context-aware responses. The framework is middleware-agnostic, supporting integration with systems like F-Prime and extending beyond aerial robotics. Aerial vehicles have revolutionized planetary exploration by enabling access to scientifically valuable but hazardous terrain beyond the reach of ground-based robots. NASA's Ingenuity Mars helicopter demonstrated the feasibility of controlled flight on Mars, completing 72 successful flights despite the planet's thin atmosphere [1], [2]. However, Ingenuity was a technology demonstrator, designed primarily to validate powered flight rather than autonomously execute complex scientific missions.