Structural Analysis and Testing of TriTruss Module Assembly

The goal of the Precision Assembled Space Structure (PASS) project was to design, model, fabricate, assemble, and characterize a 65.6-foot diameter structure utilizing TriTruss modules and multi-nut joints within a laboratory setting. The TriTruss module and multi-nut joint are novel structural components that were developed by researchers at NASA Langley Research Center to facilitate the construction of modular structures. The PASS project involved extensive structural analyses and tests based on the building-block approach. The structural analysis team conducted various analyses and tests to support the project goals, including characterizing the structural performance of the TriTruss module, multi-nut joint, TriTruss assembly, and preparing for the autonomous assembly demonstrations of TriTruss modules. A static loading test was conducted as a proof-loading test of the three-TriTruss module assembly. A static load of 621 lb was applied to the TriTruss assembly and resulting strains and deflection were measured. This paper provides the modeling approach and summary of the static loading test of the three-TriTruss module assembly with the testanalysis comparison results. Test-analysis comparison results show that the predicted strains and load-deflection response of the TriTruss assembly were within 10 percent of the test results. The test-analysis comparison study validated the modeling approach of the TriTruss assembly.