Design and analysis of non-pneumatic tire with hybrid metamaterial spoke

Nonpneumatic tires (NPTs) have recently gained more attention due to their specific advantages like no run-flat, free of maintenance, and superior load-bearing capability. In the present investigation, finite element analysis of three novel Polyurethane uniform spoke structures such as rhombus (Uni 1), hexagon (Uni 2), auxetic (Uni 3), and three of their hybrids, i.e., rhombus-hexagon (Hyb 1), hexagon-auxetic (Hyb 2), and auxetic-rhombus (Hyb 3) are performed using Ansys static structural analysis with a variety of load from 1 to 4 kN. The maximum equivalent stress at 1 kN is 51 MPa, which decreased to 7, 10, 13, 8, and 19% for Hyb 2, Hyb 3, Uni 1, Uni 3, and Uni 2. An increase in maximum equivalent stress with an increase in load is observed for all the structures. A similar trend is seen for contact pressure as well. The results align with the analytical value of relative density. The pressure distribution results illustrate that the rhombus-hexagon hybrid structure is much more uniform than the other considered structure. Finally, factor of safety results of all the samples are obtained and noted to be lies in the safe range from 1 to 2.5; however, the highest is exhibited by the rhombus-hexagon hybrid structure for potential application as NPT spoke.