Cocooning caterpillars inspire new 3D printer design
As with its SmartBird, BionicKangaroo and robotic ants, Festo's Bionic Learning Network has once again looked to the natural world for inspiration during the development of a new 3D printing solution. Rather than gradually forming an object layer by layer like a desktop extruder, the 3D Cocooner works more like a sophisticated robotic version of a CreoPop 3D printing pen, hardening the printed material with UV light as the structure is formed. Objects are created in a similar fashion to a spider spinning its web or a caterpillar making its cocoon, resulting in complex, free-standing, three-dimensional lattice structures.
For its 3D Cocooner project, Festo has taken design cues from insects and arachnids that spin or weave a fluid into a solid thread to make protective enclosures or traps for their prey. Objects created using the 3D Cocooner are made up of strands glued together to form lightweight structures freely in three dimensional space, as opposed to one layer at a time like 3D printing extruders.
Attached to the end of a tripod-like mechanical positioning system is a precision spinneret that's fed a constant thread of 2400tex glass fiber roving. This system is supplied with the necessary positional data from 3D modeling software running on a connected computer, and the spinneret handling system is also virtually represented in the custom software and depicted onscreen during both the design and the printing process.
As it leaves the spinneret, the 2 mm glass fiber thread is moved through a pair of rollers that apply a coating of UV-curing resin. It's then met by precisely-regulated UV light and hardened into a stiff rod. A small cutting disc slices the rod at a pre-programmed length and the spinneret repeats the process, joining rod to rod and building up the required structure without having to print any supports for oddly-shaped objects.
The current design offers a construction space of 450 x 300 x 600 mm (17.7 x 11.8 x 23.6 in) and a print speed of 10 mm per second. The cured glass fiber is reported to boast "astonishing tensile and bending strength" and Festo says that the 3D Cocooner platform could go on to produce shapes and structures not possible using current, conventional production methods.
Festo will be demonstrating the 3D Cocooner at Germany's Hannover Messe trade show later this month, but you can see it do its thing in the video overview below.