Determine the consequences of particle fracture during penetration

Determine whether and how particle fracture would redistribute penetrator resistance and alter the calibration and class separation between early probe response and particle Young’s modulus.

Background

The simulations treat decimeter-scale regolith particles as intact soft spheres and implement no breakage criterion, fragment generation, or post-fracture contact law. The authors note that the large overlaps and local loads in some cases make fragmentation a consequential omitted process. Consequently, the reported modulus inference is conditional on non-fragmenting particles, and the effects of fracture on probe resistance and modulus discrimination remain unresolved.

References

Fracture could redistribute probe resistance and alter the $a$--$E$ calibration and its class separation; the present inference is therefore conditional on the non-fragmenting particle assumption. Introducing breakage would require a separately calibrated strength criterion and fragment/contact representation, rather than a reinterpretation of the current 85 intact-particle runs.

— Constraining Particle Stiffness in Asteroid Regolith from Early-Time High-Speed Penetrator Dynamics under Local Granular Variability  (2610.01470 - Wang et al., 1 Oct 2026) in Section 4.2, “Applicability and model limitations”