ESA GNC Conference Papers Repository

In spring 2013, BIOMASS was selected as the 7th Earth Explorer mission at the User Consultation Meeting in Graz, Austria and will be the 4th Core Earth Explorer Mission. The overall objective of the mission is to reduce the uncertainty in the worldwide spatial distribution and dynamics of forest biomass to improve current assessments and future projections of the global carbon cycle. BIOMASS will enable the first global scale, systematic measurement of forest biomass. This objective is achieved by the implementation of a P-band Synthetic Aperture Radar (SAR) instrument. The P-band SAR is the major driver for the system design, requiring the use of a large aperture antenna in order to achieve the required coverage and performance. The antenna is a large deployable reflector (LDR) of 12 m diameter which is stowed during launch and is deployed as part of the LEOP. This paper presents the constraints put on AOCS for deploying such an antenna in a robust way, ensuring power constraint, mechanical loads constraints, and necessity of keeping collision avoidance ability.