Multiscale concurrent design of lattice scaffolds driven by structural parameters

To address the demand for customized design and prototype manufacturing of micro multifunctional scaffolds, a study was conducted on the optimal design and fabrication of flexible and elastic lattice scaffolds utilizing the digital light processing (DLP) rapid prototyping process. By combining Timoshenko beam theory, a mechanical model was established for the cell structure in three dimensions, including geometric topology, mechanical analysis, and energy absorption characteristics, and to focus on the mapping law between the geometric parameters of the cell and the mechanical model. With the lattice scaffold design under the constraint of space size taken as the main line, the NSGA-II algorithm was used to solve the multiobjective optimization and explore the optimal filling scheme with accurate matching. A novel flexible elastic photosensitive resin was prepared as forming material, and DLP forming was used to achieve high-precision and high-efficiency preparation of the corresponding lattice scaffold structure. Numerical simulations and physical experiments were used to investigate the differences between the yielded energy absorption and equivalent failure strength values of the cellular structure and the optimization target values. Results showed that the simulation and experimental results are in good agreement with the optimized target value, which proves the accuracy of the mechanical model. It can provide a theoretical basis for the subsequent development of tissue engineering skin scaffolds.