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Autonomous and optimized agile attitude control with CMGs for small satellites platforms

Programme
TDE
Programme Reference
T105-702SA
Prime Contractor
OHB SWEDEN AB
Start Date
End Date
Status
Closed
Country
Sweden
Autonomous and optimized agile attitude control with CMGs for small satellites platforms
Objectives

Develop optimised attitude control for small Earth Observation platforms using Control Momentum Gyros (CMGs) for improved pointing agility and mission availability at reduced cost

Description

Using an optimized control will enable not to oversize the CMGs and so to reduce the mission cost, but also the volume and mass, while benefiting of an enhanced agility. On previous mission with CMGs, overall guidance and control unified optimization is missing: the CMGs guidance was tuned first to ensure singularity avoidance, and then based on this tuning, an optimization was made on the feasible attitude guidance ensuring the fastest slews, and this optimization had to be performed on the ground with a significant impact on the mission planning and optimisation (margin to be taken).Taking benefits of the advances in (convex) optimization, the proposed study aims at developing an on-board optimization, reducing the impact of the mission planning, but most of all enabling an overall optimization of both the spacecraft attitude control and guidance profile and the CMG kernel guidance at the same time, for an enhanced agility in LEO Earth Observation missions. Innovation and novelty of the developed AOCS algorithms will be driving the research study, with particular focus on versatility/modularity to allow suitability for CMG units from several suppliers. Implementation tasks will make use of rapid prototyping on real time processing targets to demonstrate on board feasibility.This activity encompasses the following tasks:- Mission definition and requirements (smallsat range)- Implementation and analysis of the different low level optimizations: . real time control of the CMG kernel with singularity avoidance and torque increase objectives. offline optimization of the attitude guidance with slew stabilization time decrease objective. online optimization of the attitude guidance with slew stabilization time decrease objective- Implementation and analysis of combined higher level optimization- Implementation and analysis of the above in combination with robust control techniques (e.g. flexible mode control)

Application Domain
EO-Earth Observation
Technology Domain
5-Space System Control
Competence Domain
3-Avionic Systems
Keywords
3-Platforms / Others
Initial TRL
TRL 1
Target TRL
TRL 3
Achieved TRL
TRL 4
Public Document