VEM structural and thermal models development and testing for VERITAS and EnVision

We report on the VEM structural and thermal HW models developed for early testing of the instrument. Because of the challenging dynamic, shock load, temperature and sun illumination environment expected during the two Venus missions VERITAS and EnVision, this is of high importance, since any necessary design impact must be identified early to allow for adapting the flight model design. Three models are used for our investigations. An instrument structural model to check the dynamic and shock loads and to derive qualification loads for the subsystems. A Focal Plane Assembly Thermal Model to check the thermal behavior along the FPA chain. Finally, a flight-representative VEM baffle model for thermal qualification against sun illumination. The test results reported shall confirm the current VEM design or provide design adjustments if needed, such that the engineering qualification model can be prepared for manufacturing. EQM qualification shall be done until summer 2027 before VEM CDR.