Superelastic tire
A tire includes a plurality of SMA springs. Each SMA spring includes a first end portion, a second end portion, and an arching middle portion. Each SMA spring is interlaced with at least one other SMA spring thereby forming a laced toroidal structure extending about an entire circumference of the tire.
1. A tire comprising:
a plurality of wires having a first end portion, a second end portion, and an arching middle portion;
each wire interlaced with at least one other wire thereby forming a laced toroidal structure extending about an entire circumference of the tire; and
a selected number of wires comprising a shape memory alloy (SMA) having an austenite crystal structure in an ambient condition, and during the application of an externally applied force upon the SMA, the austenite crystal structure of the SMA reorients to a martensitic crystal structure to minimize internal strain energy and decrease local stiffness to accommodate load and large deflection of the SMA.
2. The tire as set forth in claim 1 , wherein the SMA is one of NiTi, Ag—Cd, Au—Cd, Cu—Al—Ni, Cu—Sn, Cu—Zn, Fe—Pt, Mn—Cu, Fe—Mn—Si, Co—Ni—Al, Co—Ni—Ga, Ni—Fe—Ga, Ti—Nb, β-Ti alloys, or ternary alloys or quaternary alloys of the SMA material.
3. The tire as set forth in claim 1 , wherein the SMA comprises a composition of materials designed for superelasticity, shape memory effect (SME) behavior, or both.
4. The tire as set forth in claim 1 , wherein the tire can withstand more than 1 percent strain before permanently deforming.
5. The tire as set forth in claim 1 , wherein a subset of the wires are secured to a first annular rim of a wheel and a second annular rim of the wheel.
6. The tire as set forth in claim 1 , further comprising a wheel with an annular rim at each axial side of the tire for securing the tire to the wheel.
7. The tire as set forth in claim 1 , wherein the toroidal structure defines a first ply for the tire.
8. The tire as set forth in claim 7 , further comprising a second ply, the second ply radially overlapping the first ply.
9. The tire as set forth in claim 8 , wherein the second ply comprises a laced toroidal structure having a plurality of SMA wires.
10. The tire as set forth in claim 9 , wherein each SMA wire of the second ply comprises:
a first end portion, a second end portion, and an arching middle portion, each SMA wire being interlaced with at least one other SMA wire thereby forming a laced toroidal structure extending about an entire circumference of the tire.
11. A tire comprising:
a plurality of wires having a first end portion, a second end portion, and an arching middle portion interconnecting the first end portion and the second end portion;
each wire extending radially outward from the first end portion to the middle portion and radially inward from the middle portion to the second end portion;
a plurality of wires interlaced with an adjacent wire on a first side of the wire and further being interlaced with an adjacent SMA spring on a second opposite side of the SMA spring thereby forming a toroidal structure extending about an entire circumference of the tire; and
a selected number of wires comprising a shape memory alloy (SMA) having an austenite crystal structure in an ambient condition, and during the application of an externally applied force upon the SMA, the austenite crystal structure of the SMA reorients to a martensitic crystal structure to minimize internal strain energy and decrease local stiffness to accommodate load and large deflection of the SMA.
12. The tire as set forth in claim 11 , wherein the SMA is one of NiTi, Ag—Cd, Au—Cd, Cu—Al—Ni, Cu—Sn, Cu—Zn, Fe—Pt, Mn—Cu, Fe—Mn—Si, Co—Ni—Al, Co—Ni—Ga, Ni—Fe—Ga, Ti—Nb, or β-Ti alloys, or ternary or quaternary alloys of the materials.
13. The tire as set forth in claim 11 , wherein the SMA comprises a composition of materials for pseudoelasticity, superelasticity, or shape memory effect (SME).
14. The tire as set forth in claim 11 , wherein the first end portion of each SMA wire is secured to a first annular rim of a wheel and the second end portion of each SMA wire is secured to a second annular rim of the wheel.
15. The tire as set forth in claim 11 , wherein each SMA wire forms an arch extending radially outward from a wheel.
16. The tire as set forth in claim 11 , further comprising a wheel with an annular rim at each axial side of the tire for securing the SMA wires to the wheel.
17. The tire as set forth in claim 11 , wherein the toroidal structure defines a first ply for the tire.
18. The tire as set forth in claim 17 , further comprising a second ply, the second ply radially overlapping the first ply.
19. The tire as set forth in claim 18 , wherein the second ply comprises a toroidal structure having a plurality of SMA wires.
20. The tire as set forth in claim 19 , wherein each SMA wire of the second ply comprises:
a first end portion, a second end portion, and an arching middle portion interconnecting the first end portion and the second end portion, each SMA wire of the second ply extending radially outward from the first end portion to the middle portion and radially inward from the middle portion to the second end portion,
a plurality of SMA wires of the second ply being interlaced with an adjacent SMA wire on a first side of the SMA wire and further being interlaced with an adjacent SMA wire on a second opposite side of the SMA wire thereby forming a toroidal structure extending about an entire circumference of the tire.