Speakers
Description
The proposed activity is focused on the rationalization of thermal simulators (here for operations) purpose based on existing thermal analysis model and tools. The idea is the re use of the thermal mathematical model all along the lifetime of the satellite, i.e. from the early design, the thermal analysis and control, the thermal tests on vacuum testing and the operations.
The idea is to share a common thermal model between thermal analysis and operations to allow a Spacecraft main constructor such as Thales Alenia Space to reduce the cost of the simulator implementation and increased its accuracy. The global scope is to rationalize all the thermal simulators during all the spacecraft lifetime. Today, the TAS spacecraft simulators for the functional validation (FV), software (SVF) and avionics, AIT benches have the same basis than the operations one but will not be addressed during this activity.
For this study Thales Alenia Space and DOREA choose Sentinel 3 as a study case because this satellite is already in flight and also because TAS is the manufacturer of Sentinel 3 especially the platform is well known.
A statement of work associated with a use cases study showed that having a reliable thermal simulator, allows the spacecraft constructor to validate the thermal control behaviour and the thermal margins, to correlate the thermal model with captured telemetry when testing the satellite in vacuum chamber, to correlate the thermal model in flight and many others interesting cases.
In 2022, with the financial and technical support of CNES, ESA asked to DOREA as Prime contractor and Thales Alenia Space as prime spacecraft manufacturer to implement a real time spacecraft thermal simulator demonstrator based on Sentinel 3B existing TVAC correlated thermal mathematical model in order to study the feasibility during operation use case in order to address after sales problematics during in flight missions such as energetic anomalies detection and in particular recovery testing by simulating new active thermal control characteristics.
This ESA/CNES study started with an ESATAN model including a STEP-TAS geometry provided by TAS Cannes. The presentation will show the technical locks such as the recovery of the telemetry, the initialization of the TMM temperatures based on this telemetry, but also the performances of such a simulator. This simulator has to provide a dynamic orbit propagator, a dynamic thermal regulator (PI regulation) and a dissipator especially for the platform (payload as boundary). The thermal simulator in parallel has to solve the radiative and thermal equation on the fly from a non-predictable scenario. Comparative results from a replay (7x faster than real time) will be demonstrated for the hot case and the associated telemetry.
After these results, the presentation will end with a roadmap of possible future activities in particular how to better estimate the dissipation of equipment units from telemetry and also possible future use cases demonstration.
