air-LUSI: The Mechanical and Control System Design of NASA's Airborne Lunar Observatory

Abstract

Air-LUSI is a NASA sponsored project to establish the Moon as a calibration source for Earth Observing Satellites. To do so, highly accurate radiometric measurements of the Moon must be acquired above the earth's atmosphere for a variety of lunar phases to determine a reliable lunar calibration model. By integrating a robotic telescope inside of NASA's ER-2 aircraft, the air-LUSI project produced a reliable airborne lunar observatory capable of acquiring unadulterated lunar spectra at an altitude of 70,000 feet. The robotic telescope was designed and fabricated at the University of Guelph and used a two degree of freedom gimbal with autonomous target tracking capabilities. The air-LUSI instrument was deployed in August 2018 in Palmdale, California at the NASA Armstrong Flight Research Center. The robotic subsystem performed flawlessly and tracked the Moon from a moving aircraft with an averaged tracking accuracy under 0.05 degrees.