Constrained Low-Thrust Satellite Formation-Flying Using Relative Orbit Elements : Autonomous Guidance and Control for the NetSat Satellite Formation-Flying Mission

• Main Author: Steindorf, Lukas
• Format: Others
• Language: English
• Published: Luleå tekniska universitet, Institutionen för system- och rymdteknik 2017
• Subjects: satellite; formation; control; guidance; continuous; low-thrust
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61599

This thesis proposes a continuous low-thrust guidance and control strategy for satellite formation-flying. Stabilizing feedback based on mean relative orbit elements and Lyapunov theory is used. A novel feedback gain matrix inspired by the fuel-optimal impulsive solution is designed to achieve near-optimal fuel consumption. A reference governor is developed to autonomously guide the spacecraft through the relative state-space in order to allow for arbitrarily constrained satellite formations. Constraints include desired  thrust levels, time constraints, passive collision avoidance and locally constrained state-space areas. Keplerian dynamics are leveraged to further decrease fuel consumption. Simulations show fuel consumptions of only 4% higher delta-v than the fuel-optimal impulsive solution. The proposed control and guidance strategy is tested in a high-fidelity orbit propagation simulation using MATLAB/Simulink. Numerical simulations include orbit perturbations such as atmospheric drag, high-order geopotential, solar radiation pressure and third-body (Moon and Sun) effects. Test cases include reconfiguration scenarios with imposed wall, thrust and time constraints and a formation maintenance experiment as flown by TanDEM-X, the TanDEM-X Autonomous Formation-Flying (TAFF) experiment.