Speakers
Description
Electronic systems can be adversely effected in space due to the radiation environment. Due to the available space-qualified devices often lacking the necessary performance requirements set by the satellites’ onboard softwares, commercial off-the-shelf (COTS) products are used more and more often. Testing of cosmic ray sensitivity is very challenging on Earth’s surface, thus an alternative approach is used: the RADCUBE satellite measures the cosmic radiation bombarding its sensors, while also constantly conducting measurements to determine if the onboard electronics show any discrepancy during their operation. The satellite entered orbit on 16th August 2021, and is currently orbiting Earth in a Sun-synchronous orbit with an LTDN of 10:30h, an altitude of 541/501 km, and an eccentricity of only ~0.0028. This quasi-circular orbit poses a challenging thermal environment for the satellite and its electronics, and this paper gives an overview of said thermal environment’s prediction and tasks involved in the qualification of the RADCUBE satellite. First, the orbit of the satellite and the necessary Solar parameters are described. Secondly, the paper explores the creation of the thermal mathematical model and the predicted temperature values for its subsystems. Creating a sufficiently detailed TMM with optimal run-times was a challenge in itself, however, the greatest task was modelling the different stages of mechanism deployments, taking into account the initiation of the satellite’s subsystems and their varying dissipations, and thus determining the quasi-transient commitioning phase after the first hour of satellite deployment. Then, the planned testing procedure of the PFM satellite is described, detailing the adversities experienced during the initial Thermal Balance Test, and how the manual operation of the Thermal Cycling Test was conducted. Lastly, the correlation of TMM with test data is presented, an important lesson on how testing data can show a simulation model’s shortcomings, with other lessons learned throughout the project.
