High-Power Nuclear Space Body Surface Robotics

Traditional planetary rovers operate under a severe power deficit that severely restricts their physical mobility, science throughput, and operational lifespan. Bound by low-power radioisotope sources (≈ 110 W_elec) or fragile, dust-sensitive solar panels, legacy rovers move at painstaking speeds of a few meters per hour, rely on tiny low-torque actuators, and utilize small, fragile diamond-tipped rotary drills that take days to collect a single core sample. This paper presents a high-power surface robotic architecture driven by an onboard 20-25 kW_elec electrical bus and a continuous 70-95 kW_th thermal core. By shifting from a paradigm of extreme energy scarcity to high-energy abundance, the design eliminates the tight structural mass, thermal isolation, and ultra-precise tolerance constraints that dominate traditional space robotics, fundamentally lowering R&D duration and development costs.

The core advantage of high energy abundance is the radical simplification of the engineering design loop. In conventional space robotics, engineers spend years optimizing micro-gram structural savings and custom gearboxes to operate within strict milliwatt power budgets. Access to tens of kilowatts allows the chassis and limbs to be constructed using robust, high-margin structural materials—such as high-strength aluminum alloys and commercial-grade stainless steel components—without incurring severe performance penalties. The joints utilize high-torque Quasi-Direct-Drive (QDD) electric actuators with low gear ratios. These QDD joints provide exceptional backdrivability, high dynamic compliance, and total immunity to dust jamming or gear tooth shear, enabling dynamic legged locomotion across rough terrain, steep incline scaling, and active obstacle clearing at speeds orders of magnitude faster than traditional wheeled rovers.

Thermal management and environmental survivability are similarly transformed by the primary core's continuous thermal output. Traditional rovers rely on complex, delicate electrical survival heaters or localized radioisotope heater units (RHUs) to prevent sensitive joint lubricants and avionics from freezing during the Martian night or lunar shadow. In this architecture, an active liquid-metal Sodium-Potassium (NaK-78) thermal loop continuously channels a portion of the core's 70-95 kW_th waste heat directly through the interior of all leg joints, actuator housings, and avionics bays. This maintains a continuous +20°C internal thermal baseline regardless of ambient surface conditions, completely eliminating thermal cycling stress, gear freeze-up, and cold-induced material embrittlement over multi-year operational lifetimes.

For surface resource extraction and geological sampling, the robot bypasses fragile mechanical drill bits entirely, utilizing direct atmospheric CO₂ thermal-pneumatic spalling. By drawing in ambient Martian atmospheric gas via a low-power electric compressor, the system pressurizes and superheats stored CO₂ within the core's high-temperature manifold. Pulsing this superheated, pressurized gas stream through a supersonic nozzle directly onto rock surfaces induces rapid thermal shock and localized mechanical expansion (spalling), instantly fracturing rock into micro-flakes and excavating trenches or sample bores in minutes with zero bit wear. Simultaneously, high-pressure gas pulses double as an omnidirectional dust-clearing tool, blowing fine regolith off optical sensors and docking interfaces without mechanical contact.

By loosening the structural mass and thermal isolation requirements, this high-energy robotic system slashes both R&D duration and capital expenditure. Development teams no longer need to spend years iteratively machining ultra-light exotic alloys or testing complex low-power motion profiles to survive deep freeze events. The vast energy surplus allows the robotic system to prioritize raw mechanical reliability, high structural margins, and continuous high-speed surface exploration—turning planetary surface operations from slow, passive survival exercises into active, high-throughput industrial missions.