Unit cell and structural panel assemblies with enhanced impact and noise absorption characteristics

A structural panel assembly, comprising:

• an array of unit cell assemblies, wherein each unit cell assembly comprises:
• an outer frame member spaced apart from an inner frame member;
• a plurality of quasi-zero stiffness (QZS) spring members disposed between the inner frame member and the outer frame member;
• a phononic crystal disposed between the inner frame member and the outer frame member;
• and
• a plurality of locally-resonating phononic crystal (LRPC) spring members disposed between the phononic crystal and one or more of the inner frame member and the outer frame member.

A method for forming a unit cell assembly, the method comprising the steps of:

• providing an outer frame member spaced apart from an inner frame member;
• providing a plurality of quasi-zero stiffness (QZS) spring members disposed between the inner frame member and the outer frame member;
• providing a phononic crystal disposed between the inner frame member and the outer frame member;
• and
• providing a plurality of locally-resonating phononic crystal (LRPC) spring members disposed between the phononic crystal and one or more of the inner frame member and the outer frame member;
• wherein the providing steps comprise using one or more of an additive manufacturing technique and a molding technique.