  Using an alternative mechanism to dissipation or scattering, bistable
structures and mechanical metamaterials have shown promise for mitigating the
detrimental effects of impact by reversibly locking energy into strained
material. Herein, we extend prior works on impact absorption via bistable
metamaterials to computationally explore the dependence of kinetic energy
transmission on the velocity and mass of the impactor, with strain rates
exceeding $10^2$ s$^{-1}$. We observe a large dependence on both impactor
parameters, ranging from significantly better to worse performance than a
comparative linear material. We then correlate the variability in performance
to solitary wave formation in the system and give analytical estimates of
idealized energy absorption capacity under dynamic loading. In addition, we
find a significant dependence on damping accompanied by a qualitative
difference in solitary wave propagation within the system. The complex dynamics
revealed in this study offer potential future guidance for the application of
bistable metamaterials to applications including human and engineered system
shock and impact protection devices.
