Energy absorbing assembly utilizing reversibly expandable mechanical structures for impact management and methods for operating the same
Reversibly deployable energy absorbing assemblies for impact management generally include a translatable first element, a rigid support structure and a second element having one end fixedly attached to the rigid support structure and an other end fixedly attached to the translatable first element. The second elements are adapted to plastically deform along a predefined buckling path. The predefined buckling path may be uni-modal or multi-modal depending on the desired application and/or impact conditions. Also disclosed herein are methods for operating the energy absorbing assemblies.
1. A reversibly deployable energy absorbing assembly, comprising:
a mechanical deployment mechanism comprising:
a first element in contact with a flexible covering, wherein the flexible covering includes a surface facing a vehicle interior;
a rigid support structure, wherein the first element is translatable relative to the rigid support structure, and wherein the first element is spaced apart from and substantially parallel to the rigid support structure;
at least one second element having one end fixedly attached to the first element and an other end fixedly attached to the rigid support structure, wherein the second element is fabricated from a material adapted to release elastic energy along an unbuckling path from a curvilinear shape orientation to a substantially straight shape orientation during expansion, and upon compression, a selected one of a single modal and a multi-modal buckling path from the substantially straight shape orientation to the curvilinear shape orientation; and
a releasable locking mechanism in operative communication with the first element and the rigid support structure.
2. The energy absorbing assembly of claim 1 , wherein the at least one second element is a shape memory polymer.
3. The energy absorbing assembly of claim 2 , wherein the shape memory polymer comprises at least one of polyphosphazenes, poly(vinyl alcohols), polyamides, polyester amides, poly(amino acid)s, polyanhydrides, polycarbonates, polyacrylates, polyalkylenes, polyacrylamides, polyalkylene glycols, polyalkylene oxides, polyalkylene terephthalates, polyortho esters, polyvinyl ethers, polyvinyl esters, polyvinyl halides, polyesters, polylactides, polyglycolides, polysiloxanes, polyurethanes, polyethers, polyether amides, polyether esters, poly(methyl methacrylate), poly(ethyl methacrylate), poly(butyl methacrylate), poly(isobutyl methacrylate), poly(hexyl methacrylate), poly(isodecyl methacrylate), poly(lauryl methacrylate), poly(phenyl methacrylate), poly(methyl acrylate), poly(isopropyl acrylate), poly(isobutyl acrylate) and poly(octadecyl acrylate), polystyrene, polypropylene, polyvinyl phenol, polyvinylpyrrolidone, chlorinated polybutylene, poly(octadecyl vinyl ether), ethylene vinyl acetate, polyethylene, poly(ethylene oxide)-poly(ethylene terephthalate), polyethylene/nylon (graft copolymer), polycaprolactones-polyamide (block copolymer), poly(caprolactone) dimethacrylate-n-butyl acrylate, poly(norbornyl-polyhedral oligomeric silsequioxane), polyvinylchloride, urethane/butadiene copolymers, polyurethane block copolymers, and styrene-butadiene-styrene block copolymers.
4. The energy absorbing assembly of claim 1 , wherein the rigid support structure comprises at least one of a vehicle door pillar, a vehicle header, a vehicle door interior, a vehicle dashboard, a sun visor, an armrest, a vehicle knee bolster, a vehicle floor, a vehicle headrest, a vehicle seat, a center console, a roof rail, and a vehicle seat back.
5. The energy absorbing assembly of claim 1 , further comprising a crash sensor and/or a pre-crash sensor in electrical communication with a controller, wherein the controller is in operative communication with the assembly.
6. The energy absorbing assembly of claim 1 , further comprising a releasable fastener system in combination with the energy absorbing assembly, wherein the releasable fastener system is a hook and loop fastener mechanism, wherein the releasable fastener system is in operative communication with a controller and a sensor.
7. An energy absorbing assembly, comprising:
a rigid support structure;
a first element spaced apart from and substantially parallel to the rigid support structure,
a plurality of second elements fixedly attached to the rigid support structure and the first element, wherein the plurality of second elements are substantially perpendicular to the first element and the rigid support structure when in a deployed configuration and a curvilinear shape orientation in a stowed configuration and
wherein the first element member and the rigid support structure member comprise releasable locking means with one another for providing the stowed and deployed configurations.
8. The energy absorbing assembly of claim 7 , further comprising:
at least one additional first element spaced apart from and parallel to the first element, is adapted to lockingly engage the first element in the deployed configuration; and
a plurality of additional second elements fixedly attached to the first element and the at least one additional first element, wherein the plurality of additional second elements have the curvilinear shape orientation in the stowed configuration and are substantially perpendicular to the first element and the at least one additional element when in in the deployed configuration.
9. The energy absorbing assembly of claim 8 , wherein the second elements are comprised of a shape memory polymer.
10. The energy absorbing assembly of claim 9 , wherein the shape memory polymer comprises polyphosphazenes, poly(vinyl alcohols), polyamides, polyester amides, poly(amino acid)s, polyanhydrides, polycarbonates, polyacrylates, polyalkylenes, polyacrylamides, polyalkylene glycols, polyalkylene oxides, polyalkylene terephthalates, polyortho esters, polyvinyl ethers, polyvinyl esters, polyvinyl halides, polyesters, polylactides, polyglycolides, polysiloxanes, polyurethanes, polyethers, polyether amides, polyether esters, poly(methyl methacrylate), poly(ethyl methacrylate), poly(butyl methacrylate), poly(isobutyl methacrylate), poly(hexyl methacrylate), poly(isodecyl methacrylate), poly(lauryl methacrylate), poly(phenyl methacrylate), poly(methyl acrylate), poly(isopropyl acrylate), poly(isobutyl acrylate) and poly(octadecyl acrylate), polystyrene, polypropylene, polyvinyl phenol, polyvinylpyrrolidone, chlorinated polybutylene, poly(octadecyl vinyl ether), ethylene vinyl acetate, polyethylene, poly(ethylene oxide)-poly(ethylene terephthalate), polyethylene/nylon (graft copolymer), polycaprolactones-polyamide (block copolymer), poly(caprolactone) dimethacrylate-n-butyl acrylate, poly(norbornyl-polyhedral oligomeric silsequioxane), polyvinylchloride, urethane/butadiene copolymers, polyurethane block copolymers, styrene-butadiene-styrene block copolymers, or copolymers thereof.
11. The energy absorbing assembly of claim 7 , wherein the rigid support structure comprises one of a vehicle door pillar, a vehicle header, a vehicle door interior, a vehicle dashboard, a sun visor, an armrest, a vehicle knee bolster, a vehicle floor, a vehicle headrest, a vehicle seat, a center console, a roof rail, or a vehicle seat back.
12. The energy absorbing assembly of claim 7 , further comprising a crash sensor and/or a pre-crash sensor in electrical communication with a controller, wherein the controller is in operative communication with the assembly.
13. The energy absorbing assembly of claim 7 , further comprising a covering on the assembly.
14. A process of operating an energy absorbing assembly, comprising:
attaching the energy absorbing assembly to a rigid support structure, wherein the energy absorbing assembly consists essentially of a mechanical deployment mechanism comprising a first element spaced apart from and translatable relative to the rigid support structure, at least one second element having one end fixedly attached to the first element and an other end fixedly attached to the rigid support structure, wherein the first element is in contact with a flexible covering, wherein the flexible covering includes a surface facing a vehicle interior, wherein the second element is fabricated from a material adapted to release elastic energy along from a curvilinear shape orientation to a substantially straight shape orientation during deployment, and upon impact, plastically deform along a predefined buckling path from the substantially straight shape orientation; and
sensing an impact event or an imminence of the impact event and deploying the energy absorbing assembly.
15. The process of operating the energy absorbing assembly of claim 14 , wherein the predefined buckling path is multi-modal.
16. The process of operating the energy absorbing assembly of claim 14 , wherein the predefined buckling path is uni-modal.
17. The process of operating the energy absorbing assembly of claim 14 , wherein the at least second element comprises a shape memory polymer.
18. The process of operating the energy absorbing assembly of claim 14 , wherein the rigid support structure comprises one of a vehicle door pillar, a vehicle header, a vehicle door interior, a vehicle dashboard, a sun visor, an armrest, a vehicle knee bolster, a vehicle floor, a vehicle headrest, a vehicle seat, a center console, a roof rail, and a vehicle seat back.