Status of Technology Demonstration for a Drag-Free CubeSat
Session
Pre-Conference: CubeSat Developers' Workshop
Abstract
A drag-free satellite is freed of all forces but gravity. A free floating test mass inside the satellite acts as gravitational reference and a control system maintains the satellite’s position relative to the test mass. The position of the test mass is measured with a differential optical shadow sensor. The entire system furthermore includes a caging mechanism to lock the test mass during launch and a UV LED based charge management system to reduce the effects of electrostatic forces between the test mass and its housing. Drag-free satellites have been flown in the past, however, the nature of the gravitational reference sensor and the disturbance compensation system of the proposed Drag-free CubeSat differ in many aspects and therefore need to be space qualified in order to reduce the overall risk for the drag-free mission. Here we show the recent progress made in this process. The differential optical shadow sensor has been redesigned to fit in the envelope of a CubeSat payload and has undergone first qualification and performance tests. The caging mechanism is scheduled to fly on a zero-g parabolic flight where the uncaging and re-caging capabilities are demonstrated. The UV LED charge management system is scheduled to launch on a microsatellite in September. Together, these technology demonstrations raise the TRL of the main subsystems of the gravitational reference sensor and the disturbance compensation system and enable a successful Drag-free CubeSat mission.
Presentation Slides
Status of Technology Demonstration for a Drag-Free CubeSat
A drag-free satellite is freed of all forces but gravity. A free floating test mass inside the satellite acts as gravitational reference and a control system maintains the satellite’s position relative to the test mass. The position of the test mass is measured with a differential optical shadow sensor. The entire system furthermore includes a caging mechanism to lock the test mass during launch and a UV LED based charge management system to reduce the effects of electrostatic forces between the test mass and its housing. Drag-free satellites have been flown in the past, however, the nature of the gravitational reference sensor and the disturbance compensation system of the proposed Drag-free CubeSat differ in many aspects and therefore need to be space qualified in order to reduce the overall risk for the drag-free mission. Here we show the recent progress made in this process. The differential optical shadow sensor has been redesigned to fit in the envelope of a CubeSat payload and has undergone first qualification and performance tests. The caging mechanism is scheduled to fly on a zero-g parabolic flight where the uncaging and re-caging capabilities are demonstrated. The UV LED charge management system is scheduled to launch on a microsatellite in September. Together, these technology demonstrations raise the TRL of the main subsystems of the gravitational reference sensor and the disturbance compensation system and enable a successful Drag-free CubeSat mission.
