ESA GNC Conference Papers Repository
Sun avoidance implementation on safe modes for LEO satellites
Some observation satellites may embark payloads that have constraints in term of Sun illumination. This kind of constraint is not compatible with conventional safe modes that do not take into account attitude control in their preliminary phases, and then may lead to hazardous configuration for payloads. Thales Alenia Space has developed a specific safe mode, based on potential law method, that allows to manage this category of attitude linked constraints. This safe mode has been implemented and tested on one observation satellite in orbit. First part of presentation will recall and detail the constraints, as well as a trade-off of design and work-around to manage them. Second part will present the overall architecture of the mode, with the background theory behind potential law method. Third part will be focused on expected satellite behaviours, and their comparison with in-flight results.