Duration: 4 months
The deployment of the BIOMASS satellite's 12m-diameter reflector followed a traditional approach by initially disabling the AOCS and then using a time-consuming stabilization sequence involving two modes (Acquisition & Safe Hold (ASH) mode and Normal Mode (NM)). This process took between three and six days, posing a significant collision risk, since the satellite could not perform collision avoidance maneuvers during most of the deployment. Secondly, a huge engineering effort was put into tuning the controllers due to the significant inertial and structural variations. Many future space missions will use similar large deployable structures, so faster and easier to design and tune deployments are essential. In this project, we propose a methodology based on adaptive control laws to bring these improvements to the BIOMASS case. Our approach includes recent developments that overcame long-standing difficulties in finding control-oriented models for closed kinematic chains. With these innovative models, control laws that adapt to the system's evolving structural and inertial properties can be rapidly synthesized. Then, high-fidelity multibody simulations will be performed to validate the results. The advanced control expertise within the ESA team is crucial for confronting our solution with the operational and performance constraints of European missions. This collaborative work aims to validate innovative solutions, adapting our approach to meet industrial needs for complex applications. All in all, this work will significantly reduce deployment time but also the related engineering effort for missions like BIOMASS, demonstrating a control framework with applications for other complex challenges, such as on-orbit assembly.
