Autonomous Robotic Mining at 430 °C: System Design for Mercury Surface Operations

We present a complete system design for an autonomous mining excavator intended for continuous operation on the surface of Mercury, the most thermally extreme solid surface in the inner solar system. The Mercury Mining Excavator (MME-100) must operate at 430 °C dayside surface temperature in hard vacuum under 6,272-14,448 W/m^2 solar irradiance, with 4.3-12.3 minute one-way light delay to Earth precluding real-time teleoperation. The 2,200 kg six-wheeled rover employs a rocker-bogie suspension heritage-adapted from Mars Science Laboratory, a 6-DOF articulated excavation boom with 0.3 m^3 bucket, and a 1.5 m^3 self-dumping hopper. All actuators use samarium-cobalt (SmCo) permanent magnets (Curie temperature 727 °C), solid-state lubricants (MoS_2/WS_2 in vacuum), and Inconel 718 harmonic drive flex splines rated to 700 °C. The sensor suite comprises stereo navigation cameras, scanning LIDAR, laser-induced breakdown spectroscopy (LIBS) for ore grading, and a 20-element platinum RTD temperature monitoring array. Computing architecture is dual-redundant radiation-hardened processors (RAD5545-class) with an FPGA co-processor for terrain classification and a silicon carbide (SiC) auxiliary processor operating at ambient temperature for motor safety control. Thermal management employs a 30-layer MLI enclosure with NaK eutectic heat pipe cooling to 6.0 m^2 deployable radiators. The autonomy architecture progresses from SAE Level 2 (supervisory control from Earth) through Level 4 (full autonomous operation with human override) within two years of deployment, using a three-level fault detection, isolation, and recovery (FDIR) hierarchy spanning hardware watchdog, onboard autonomous response, and ground-in-the-loop intervention. Multi-robot coordination for fleet mining operations employs a distributed task allocation protocol with local conflict resolution, enabling 10-50 excavators to operate cooperatively across a mining field without continuous Earth oversight. Comparison with Mars rover heritage (Curiosity, Perseverance), terrestrial autonomous mining platforms (Caterpillar CMD), and proposed lunar ISRU systems demonstrates that Mercury surface mining requires autonomy levels and thermal design margins significantly beyond current state of the art. A technology readiness assessment identifies SiC power electronics (TRL 5-6), high-temperature harmonic drives (TRL 4), and autonomous geological assessment (TRL 3) as the critical development items.