Design, Manufacture and Degradation of Fluorosilicone mechanism due to Space Exposure on the MISSE module at the International Space Station
Academic Article in Scopus
Lunar dust has posed significant challenges in space exploration, leading to clogged mechanisms, abrasion, seal failures, loss of traction, and thermal control issues. The Uurich project was developed to assess the performance of compliant mechanisms specifically designed to enhance resilience to lunar dust when exposed to the space environment. As part of this initiative, the Uurich mechanism was designed for compatibility with the Materials International Space Station Experiment (MISSE) platform aboard the International Space Station (ISS) enabling direct exposure to the conditions of Low Earth Orbit (LEO). Uurich is a mechanism designed to assess the suitability of compliant mechanisms to space applications, where resistance to dust is critical. Regolith (lunar dust) has been one of the biggest challenges in previous Space Missions, including Apollo. In 2023, the Uurich mechanism was launched to the ISS aboard the SpaceX CRS-27 mission from NASA's Spaceport in Cape Canaveral. Over six months, the mechanism remained in the MISSE module undergoing periodic imaging and data collection to monitor its behavior in space. After this period, the mechanism was returned to Earth and the collected data retrieved. This data is crucial to characterize the environmental conditions and understand the factors that influenced the sample's performance in space. Fluorosilicone, the material used in Uurich, offers advantages over conventional silicone. including hydrophobicity. lower density, and enhanced chemical resistance and tensile strength. However, it also exhibits reduced electrical insulation properties, and decreased elasticity at high temperatures, leading to hardening, and mass loss. To assess these effects, post-flight experimental tests, including X-ray tomography, thermography. and tensile testing will compare space-exposed samples with unexposed controls. Preliminary processing of the data retrieved from serisors onboard the MISSE module exhibits a strong resemblance to a polynomial function between beta angle and temperature experienced by the device. The relationship between these magnitudes and time approximates a sinusoidal function due to the ISS navigating Earth's circumference 16 times per day and Earth moving around the sun. This temperature and sun exposure behavior will directly relate to the sample's degradation, which is currently under investigation and will be discussed in the manuscript's results. This research provides insights into the behavior of compliant mechanisms and advanced materials in space, offering valuable lessons in spatial design, manufacturing, and environmental resilience. The findings will contribute to the broader understanding of material performance in extraterrestrial environments, supporting future space exploration missions.
