Validation of On-Orbit Thermal Deformation and Finite Element Model Prediction in X-Ray Astronomical Satellite Hitomi

抄録

The validation of deformation caused by the thermal expansion of structures is an important issue for the success of a mission that requires the large-scale and precise positioning of instruments. Therefore, an accurate alignment monitor system was installed in the X-ray astronomy satellite Hitomi to correct observation data. We compared the analysis results of a finite element model with the flight telemetry data of the alignment monitor installed on Hitomi to validate the finite element model. As a result, it was shown that the finite element analysis was able to reproduce the global and slow trends of thermal deformation on orbit. However, the analysis could not reproduce the rapid changes in thermal deformation. To realize more precise and large structures in the future, we need to identify these rapid changes and correctly improve the FE model of thermal deformation through ground tests prior to launch.