Regolith simulant preparation methods for hardware testing

To qualify hardware for space flight, great care is taken to replicate the environment encountered in space. Emphasis is focused on presenting the hardware with the most extreme conditions it might encounter during its mission lifetime. The same care should be taken when regolith simulants are prepared to test space system performance. Indeed, the manner a granular material is prepared can have a very high influence on its mechanical properties and on the performance of the system interacting with it. Three regolith simulant preparation methods have been tested and are presented here (rain, pour, vibrate). They should enable researchers and hardware developers to test their prototypes in controlled and repeatable conditions. The pour and vibrate techniques are robust but only allow reaching a given relative density. The rain technique allows reaching a variety of relative densities but can be less robust if manually controlled.

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