Development of a High Precision Thrust Balance

A new AOCS called “High Precision Attitude and Orbit Control System Based on the Emission of Electromagnetic Radiation” (PACER) is currently under development at the Institute of Space Systems (IRS) of the University of Stuttgart. This thesis deals a new high precision thrust balance in the sub micro-Newton range, with a new concept of active damping system, based on the emission of electromagnetic waves. The chosen radiation source are LEDs because of the low thermal radiation component, the low energy consumption and the continuous improvement of this technology in recent years. Goal of this project will be the measurement of the light pressure emitted by LEDs, to evaluate a possible use of these technology for the PACER. The motivation for the investigation of a such system based on upcoming and planned satellite missions within the commercial and scientific sector, where an ever-increasing demand on precision accuracy can be observed. For example, the “Lisa Pathfinder” mission demands on the AOCS require thrust as low as 1 μN with a thrust noise of 0,1 μN and a lifetime of 5 years. A steady-state thrust stand based on a fiber-suspended torsion pendulum was developed, with thrust range 50 nN - 400 nN and a sensibility of 25 nN, that can be controlled and monitored by a PC using MATLAB, with a revolutionary damping system and an estimated cost less than 1000€. This stand could represent an excellent compromise for a first evaluation of the effects of electromagnetic radiation propulsors.