Full-Scale Testing of Portable and Automatic High Altitude Balloon Launching Platform

Abstract

This paper presents subsystem prototypes and tests of a novel design architecture to autonomously inflate and launch high altitude balloons (HABs). Three core subsystems were previously tested at reduced scale utilizing a 350-gram balloon; this paper test these subsystems at full scale, in the field, utilizing a full-scale, 1500-gram balloon. A first subsystem, the Balloon Capsule is a rigid container that utilizes a novel packing technique, allowing a latex balloon to be safely transported. Internal geometry of the capsule passively controls slack of the balloon during inflation. A second subsystem, the Helium Engagement and Locking System (HEL), oversees connecting the helium supply, locking the balloon in place, sensing lift values, and launching the balloon. A third subsystem, the Balloon Inflation Barrier (BiB), supports the balloon during inflation and prevents excessive deflection during high winds. Results from full scale compressed air testing showcased a need for a neoprene based internal retention mesh for the Balloon Capsule. Both the HEL and BiB performed satisfactorily. Helium tests concluded the Balloon Capsule performed as designed in light winds and failed at medium winds due to the excessive unreeling of balloon slack. The HEL system was actuated manually and successfully locked, inflated, and released a full scale 1500- gram balloon with lift values exceeding 2.26 kg. The BiB performed as expected when balloons were fully inflated, however, during inflation, BiB's failed at high winds due to structure buckling and excessive balloon slack. The full scale autolauncher prototype weighs less than 11 kg and is 1.2 m long, 1.2 m wide, and 1.1 m tall. This design allows one person to inflate and launch a balloon in under 30 mins. Critical elements of future work include the refinement of BiB structure, the automation of the HEL system, and implementation of the helium gas control logic; and the design of balloon payload storage system.