Session
Advanced Technologies Research & Academia 1
Location
Salt Palace Convention Center, Salt Lake City, UT
Abstract
Deployable solar arrays are among the most failure-prone structures on spacecraft, and on small satellites their large area, low mass, and mechanical complexity make faults both more likely and harder to observe. Electrostatic discharge, string arcing, and localized hot spots can degrade or disable an array, yet the mass and harness penalties of distributed point sensors are difficult to accommodate within CubeSat resource budgets. This paper presents a passive, camera-readable sensing skin based on spin crossover (SCO) composite films that converts thermal events on a large-area structure into persistent optical information. The active material, [Fe(NH2trz)3]Br2, undergoes a reversible molecular spin transition near room temperature that is accompanied by pronounced changes in reflectance, permittivity, and magnetic moment, and that exhibits thermal hysteresis. We disperse the complex in a thermally cured silicone elastomer to produce thin, flexible films that can be laminated onto deployable substrates. We characterize the thermally driven optical response of the pure complex and of composites at 10–50 wt% loading, showing a reversible pink-to-pale color change that a standard onboard camera can resolve. Because the transition is hysteretic, a transient temperature excursion is recorded as a lasting visual change, allowing an intermittent fault to be detected after the fact without continuous monitoring. Laser engraving is used to spatially pattern the films at sub-millimeter resolution, enabling multi-zone layouts and reveal-and-conceal encoding on a single skin. We further report the temperature-dependent dielectric and magnetic behavior of the composites, which point toward complementary electrical and magnetic read-out modalities. Together these results outline a lightweight, multifunctional approach to structural health monitoring of large-area space structures that adds sensing capability with minimal mass, volume, and electrical overhead.
Document Type
Event
Passive Thermal Imaging and Failure Detection of Large-Area Space Structures Using Spin Crossover Composite Skins
Salt Palace Convention Center, Salt Lake City, UT
Deployable solar arrays are among the most failure-prone structures on spacecraft, and on small satellites their large area, low mass, and mechanical complexity make faults both more likely and harder to observe. Electrostatic discharge, string arcing, and localized hot spots can degrade or disable an array, yet the mass and harness penalties of distributed point sensors are difficult to accommodate within CubeSat resource budgets. This paper presents a passive, camera-readable sensing skin based on spin crossover (SCO) composite films that converts thermal events on a large-area structure into persistent optical information. The active material, [Fe(NH2trz)3]Br2, undergoes a reversible molecular spin transition near room temperature that is accompanied by pronounced changes in reflectance, permittivity, and magnetic moment, and that exhibits thermal hysteresis. We disperse the complex in a thermally cured silicone elastomer to produce thin, flexible films that can be laminated onto deployable substrates. We characterize the thermally driven optical response of the pure complex and of composites at 10–50 wt% loading, showing a reversible pink-to-pale color change that a standard onboard camera can resolve. Because the transition is hysteretic, a transient temperature excursion is recorded as a lasting visual change, allowing an intermittent fault to be detected after the fact without continuous monitoring. Laser engraving is used to spatially pattern the films at sub-millimeter resolution, enabling multi-zone layouts and reveal-and-conceal encoding on a single skin. We further report the temperature-dependent dielectric and magnetic behavior of the composites, which point toward complementary electrical and magnetic read-out modalities. Together these results outline a lightweight, multifunctional approach to structural health monitoring of large-area space structures that adds sensing capability with minimal mass, volume, and electrical overhead.
