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Self-actuated deployable space structures present a novel challenge for deployment dynamics modeling efforts, where the system-level influence of strain energy components must be captured. Here, the free deployment of an origami-folded structure through actuation of strain energy hinges is studied. Studies include experimental testing, multibody dynamics modeling, and finite element modeling. An approach for modeling high strain tape spring hinges for use in a multibody simulation of free-deployment dynamics analysis is presented and demonstrated. This approach considers hinges with multiple degrees of freedom beyond the primary fold axis angle. A novel folded deployable structure is designed and prototyped with a segmented fold pattern and strain energy hinges integrated in the design. A suite of deployment tests is conducted on the prototype using videogrammetry. A full simulation of the prototype is constructed from a multibody dynamics model and the hinge model, and the predicted deployment behavior for relative hinge states is evaluated against the experimental testing. Additionally, the prototype deployment is replicated using an explicit dynamic finite element analysis for a performance comparison. The models demonstrate strong correlation for deployment time predictions across the relative hinge states, and the finite element analysis correlates all deployment behaviors. [ABSTRACT FROM AUTHOR]

The Near-Earth Asteroid Characterization and Observation (NEACO) mission is a concept study proposing to explore the fast-rotating asteroid (469219) 2016 HO3, one of Earth's few quasi-satellites. In this study, a SmallSat spacecraft performs a scientific investigation that characterizes the asteroid at a sufficient degree to enable future, more in-depth missions. The 166 kg NEACO spacecraft uses a low-thrust, solar electric propulsion system to reach HO3 within 22 months from launch. Its instrument suite consists of two optical cameras, two spectrometers, an altimeter, and a low-velocity impactor. Upon arrival at HO3, NEACO uses pulsed plasma thrusters to hover at varying altitudes to enable lit surface mapping, shape modeling, and surface spectroscopy. The spacecraft will then perform several flybys to estimate the asteroid's mass. Finally, NEACO releases a low-velocity impactor during very low-altitude hovering to validate the existence of regolith and estimate the magnitude of surface cohesion. The science operations are completed within 8 months and the total mission is completed in less than 3 years. The NEACO mission concept integrates novel small-body analyses and proximity operation techniques with high-technology-readiness-level spacecraft components to achieve its science objectives within a reasonable mission timeline. [ABSTRACT FROM AUTHOR]