Porous scaffold design by solid T-splines and triply periodic minimal surfaces

Abstract

Due to its high interconnectivity and smooth surface, the triply periodic minimal surface (TPMS) has become a promising porous structure applied as tissue engineering scaffold, lightweight filling and micro-reactor. Yet, it is still a tough challenge to meet the authentic flexible demands by current TPMS design methods. In this work, a complete TPMS porous scaffold design method based on solid T-splines is proposed. In order to give full play to advantages of TPMS, the parameter influences on the volume specific surface area and porosity are analyzed, respectively. Then, a novel solid T-spline based heterogeneous porous scaffold design solution is offered, including TPMS scaffolds with non-uniform threshold, period and unit. Initially, a complex solid T-spline model can be approximately represented by sampled hexahedron elements. Eventually, these sampled hexahedron elements are redivided into tetrahedrons for TPMS extraction by the Marching tetrahedra algorithm. The information for designing TPMS, including the external volume, internal unit parameters can be represented via solid T-splines. The TPMS can be directly extracted from the solid T-spline designed volume which is homeomorphic to a cube. The final TPMS scaffold is saved as STL model and manufactured via additive manufacturing technology. Experimental results support the effectiveness as well as the flexibility of this solid T-spline based TPMS scaffold design method.