THE GRIFFITHS FREE FLYING EVA LOGISTICS SLED (NGLS)

The Griffiths Free‑Flying EVA Logistics Sled (NGLS) Griffiths, Wayne (2026) This paper introduces the Griffiths Free‑Flying EVA Logistics Sled (NGLS), a cold‑gas‑propelled, six‑degree‑of‑freedom mobility platform designed to support heavy‑load external operations around large spacecraft, orbital platforms, and deep‑space installations. The NGLS addresses a critical capability gap in modern EVA logistics by enabling astronauts to transport tools, replacement modules, and structural components far exceeding suit‑carried limits, while maintaining precise, stable maneuverability in microgravity environments. The system integrates dual high‑pressure nitrogen tanks, vectoring thruster assemblies, autonomous stabilization, and a modular cargo interface into a lightweight composite frame. A rod‑based manual controller provides intuitive EVA‑glove‑compatible handling, while teleoperation and autonomous modes support hazardous or repetitive tasks. Redundant thruster pathways, fail‑closed valves, dead‑man stabilization, and collision‑avoidance sensors form a comprehensive safety architecture suitable for human‑rated operations. The paper presents the full engineering architecture of the NGLS, including propulsion modelling, structural load paths, control algorithms, power and thermal management, and a detailed FMEA‑based safety analysis. Performance modelling demonstrates operational Δv in the 50–150 m/s range, sortie durations of 10–45 minutes, and payload capacities of 50–200 kg depending on mission profile. Comparative analysis highlights the sled’s advantages over SAFER, MMU, and robotic‑arm‑based logistics approaches. The Griffiths NGLS forms part of an ongoing series of deep‑space systems research exploring practical, near‑term architectures for habitat support, propulsion, and EVA operations. This work contributes a dedicated logistics platform to the broader Griffiths mission‑class ecosystem, enabling safer, more efficient, and more capable external maintenance workflows for future crewed missions Follow me on LinkedIn: www.linkedin.com/comm/mynetwork/discovery-see-all?usecase=PEOPLE_FOLLOWS&followMember=wayne-griffiths-22a52a36