NASA JPL: High-Endurance Lighter-Than-Air In-Situ Observation System (HELIOS)

Abstract

As advised by engineers at NASA’s Jet Propulsion Laboratory, existing methods for analyzing anthropogenic climate impacts, such as satellites and stratospheric balloons, are too costly and cannot take in-situ measurements related to transient or cyclic human activity, such as rush hour traffic emissions. A scale prototype flight system to take such measurements, dubbed HELIOS, was developed, consisting of a 5.6-meter nonrigid airship drone with four distinct subsystems: structure, payload, power plant, and guidance, navigation, and control (GNC). The structure subsystem consisted of an aerodynamic envelope with a lifting capacity of 8.168 kg and actuated control fins. The payload subsystem encompassed a modular rack and frame assembly capable of supporting a variety of flight system configurations, as well as a sensor suite suited to emissions analysis. The power plant subsystem utilized a solar-combustion engine hybrid architecture to provide propeller thrust and electrical power distribution. The GNC subsystem developed a global communication platform and robust remote and autonomous control systems, facilitating continuous tracking and precise maneuvering of the flight system. To evaluate viability for flight, subsystem components were independently characterized through laboratory experiments and analysis, yielding a projected flight endurance of 7 hours in a 7 m/s headwind. Subsystems were subsequently integrated, and an integrated flight test was conducted at Crow Island Airfield. Two seconds into the flight, a wind gust led to a rapid unscheduled disassembly of the flight system. Future flight testing is planned to collect additional data on flight performance. Despite limited flight success, HELIOS has demonstrated proof-of-concept of a high endurance flight system for in-situ climate analysis at an extremely low price point relative to satellites and stratospheric balloons.