Experimental Testing of a 30-Meter Triangular, Rollable, and Collapsible Composite Deployable Boom

Predictable structural response and stability of long, slender booms are important considerations toward ensuring mission success for space systems relying on deployable structures. The buckling response of thin-walled structures can be sensitive to geometric imperfections. As experimental testing of large (>20 meters) and compliant space deployable structural systems is challenging in the Earth’s gravity, increased reliance on analysis models can introduce risk to mission success. Additionally, current analysis models of components within the structural system often remain unvalidated because of those challenges. To study the response of long, imperfection-sensitive thin-walled space deployable booms, NASA Langley Research Center partnered with Redwire, Inc. to design, develop, and demonstrate quasi-static structural testing capabilities for a 30-meter triangular, rollable, and collapsible (TRAC) boom test article for analysis model improvement and correlation. The motivation, setup, instrumentation, and results from multiple quasi-static bend and combined compression, bend, and torsion tests loaded in different directions relative to the cross-section of the boom are used to evaluate the response of the test article. Specific tests were conducted twice to provide insight into the repeatability of the observed response. Tests across multiple loading conditions were repeatable. Localized elastic flange buckling was observed to be the most frequent collapse mode. The lessons learned from testing the 30-meter boom as part of the Gravity Offloading and Analysis of Long Imperfection-sensitive Elements (GOALIE) project can inform future test development for large deployable composite space structures.