KY EPSCoR Science: Coordinated Position and Attitude Control for Small Satellites

Small-satellite swarms are an integral part of future space missions, including exploration, atmospheric measurements, comet detection, cosmological and biological studies, and space-weather monitoring. Small- satellite formations are candidates for next-generation interferometers, large-aperture space telescopes, antennas, radiometers, and gravity-wave detectors. The primary actuation-and-sensing challenge for small satellites is their strict size-and-weight limitations. Conventional large-satellite actuation systems (e.g., propellant thrusters and reaction wheels) are not well suited for small satellite swarms. This project will develop and integrate innovative actuation, sensor, and control technologies that are both small, efficient, and have renewable power sources. The objective of this project is to develop and integrate three key enabling technologies: 1) a noncommutative-attitude-control (NAC) system for orientation control, 2) an electromagnetic actuation-plus-sensing (EAS) system for relative- position control and sensing, and 3) discrete-time formation (DTF) control algorithms that address the unique features of the NAC and EAS systems. The research team is currently applying noncommutative- attitude-control for medical microrobots and discrete-time formation control algorithms for multi-vehicle aerial distributed sensing systems. The unique combination of technologies developed in this project will advance the state-of-the-art in small satellite swarms for NASA. These technologies will also have broader application for NASA challenges such as formations of large satellites and small terrestrial robots. Our research plan includes collaborations with NASA Ames (ARC), NASA Kennedy Space Center (KSC), NASA Marshall Space Flight Center (MSFC), and industry partner Space Tango Inc. This plan leverages the research team's recent developments on small-satellite attitude control, discrete-time formation control, and electromagnetic formation-flying technology (KSC), as well as expertise on video guidance sensors and small- satellite design and testing (MSFC). Major milestones of this project include a 5-satellite cooperative-control experiment using MSFC's flat-floor facility, and a 2-satellite formation-flying experiment using Space Tango's TangoLab-1 facility on the International Space Station (ISS). After successful completion of this project, our research roadmap envisions follow-on projects including satellite formation-flying experiments in orbit. This proposal leverages results of prior NASA EPSCoR seed investments to build unique experimental infrastructure that expands Kentucky's research capability in a new dimension, develops specialized knowledge and expertise for faculty and students, increases collaborations between Kentucky's researchers, start-up companies and NASA, and supports future research funding success. The work aligns with the Kentucky Science and Innovation Strategy priority for High-Value Research and Development. The proposed research directly supports NASA Space Technology Mission Directorate (STMD), specifically, the Small Spacecraft Technology Program (SSTP), which is tasked with identifying and developing new technologies to enhance or expand the capabilities of small spacecraft and support flight demonstrations of new technologies. This project has a high potential to impact future NASA missions and produce technologies for the growing U.S. small-satellite sector.