The shared open-source library of tissue engineering scaffolds has been designed following biomimetic design principles, trying to achieve porous structures capable of imitating the porosities, mechanical properties and geometrical morphologies of human tissues, for improved performance as tissue engineering scaffolds. The final biomechanical properties will depend on the actual technologies and materials employed for manufacturing (printing) the CAD models, for which the provided design and characterization maps have been given with relative properties (adimensionalized properties obtained dividing by the density and mechanical moduli of the bulk materials used for manufacturing).

In any case, the following general principles have been considered:

• Porosity values above 50% and, in most cases in the 75%-95% range, have been considered to obtain highly porous and interconnected tissue engineering scaffolds following recommendations from medical practicioners.
• Geometries have been designed for additive manufacturing, that is, the actual printing options and materials have been taken into account to design viable geometries.
• According to the current state-of-the-art and foreseeable advances in terms of precision and resolution, for the mentioned technologies and printable volumes, cross-sectional diameters of 150 mm, 250 mm and 500 mm are used for the interconnecting elements. Only for the more conventional “woodpile” structures, common of fused-deposition modelled scaffolds but also fabricable through additive photopolymerization tools, square cross-sections of 400 mm x 400 mm are chosen, taking account of the dimensions typically printable with polymeric extruders. 
• Voxel-based and pixel-based design procedures also help to optimize printability and to reach the technological limits, especially for inkjet and polyjet processes, for which pixels of 40 x 40 mu² and voxels of 40 x 40 x 40 mu³ are employed, according to the features of technologies available within our team. 
• Scaffolds are designed to fit a nominal unit cell of 10 x 10 x 10 mm³.