In 2014, the first study on the design, fabrication and hydrodynamic testing of a flexible 3D printed
synthetic shark skin membrane was demonstrated (Wen et al., 2014). The authors used 3D models
of denticles based on high-resolution micro-computed tomography (micro-CT) scans of the skin of
a shortfin mako shark. Multi-material PolyJet 3D printing (Objet Connex500 3D printer capable of
multi-color and multi-material printing) was used to fabricate thousands of rigid synthetic shark
denticles on a flexible membrane (Fig. 6). The Young’s modulus of the rigid denticles and the flexible
membrane was about 1 GPa and 1 MPa, respectively. The 3D printed shark skin showed increased
swimming speed with reduced energy consumption compared to control models that lacked denticles.
Although the authors were able to retain the full surface complexity of natural shortfin mako shark
denticles (∼150 μm in size with surface features down to 5–10 μm), they could not fabricate the
3D printed replicas at the biological scale due to limitations on printing resolution using the current
multi-material 3D printing technology.
The fluid flow through the complex internal skeletonized respiratory structures (hydrospires) of
spiraculate blastoids is not fully understood. In a recent demonstration, the fluid flow through scaledup
(72×) 3D printed (ProJet HD3000 MultiJet 3D printer) models of the complex skeletonized respiratory
structures of a blastoid echinoderm using a translucent ABS polymer was studied