We employ an evolutionary algorithm to investigate the optimal design of composite protectors using one-dimensional granular chains composed of beads of various sizes, masses, and stiffnesses. We define a fitness function using the maximum force transmitted from the protector to a “wall” that represents the body to be protected and accordingly optimize the topology (arrangement), size, andmaterial of the chain.We obtain optimally randomized granular protectors characterized by high-energy equipartition and the transformation of incident waves into interacting solitary pulses. We consistently observe that the pulses traveling to the wall combine to forman extended (long-wavelength), small-amplitude pulse.
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