The Bug

The Bug explores new methods of additive manufacturing, focusing in the fields of fiber composites. Unlike traditional FDM layering and slicing systems, The Bug seeks to fabricate 3-D objects by placing a continuous non-woven fiber shell like structure.

Composites have been present for tens of thousands of years now. Although they exist naturally in nature, humans have significantly evolved them into technologically advanced materials that today offer advantages like strength-to-weight ratio, flexibility and insulating properties.

This project is the product of an independent study that took place during my last semester as an undergraduate student at the Illinois Institute of Technology.

Process

Perhaps one of the toughest challenges for freeform 3D printing is selecting the material to print with, in this case, selecting the ingredients for the composite.

Resin testing and fiber selection

The extrusion has to be able to retain the desired shape and position immediately after being placed. This becomes increasingly challenging when there is no support material to anchor against.

The resin had to have a low enough viscosity to permeate into the thread, among the individual fibers.  By achieving that, the resin would harden inside the thread, locking the interstitial space between fibers, similar to how carbon does in iron to create steel.

 

Extruder Design

Extruder design and iterations 

The extruder went though several cycles of iteration; finalizing with a set of six high power UV LEDs capable of curing the extruding thread in less than 1s. The gravity fed resin reservoir was replaced by a precisely controlled peristaltic mixer.

Future work would include using lasers to cure the resin even faster and more selectively. Heating the resin before entering the mixer to further lower its viscosity, achieving a faster saturation of the interstitial space.

 

Generating the Path

Path Simulation 

Algorithm decision flow chart

Using Processing we can open a 3D model, abstract the points and then generate a single linear path to cover the entire surface. Further research and testing led to the creation of a new algorithm to include supports. This was inspired by how spiders architect their webs, first with structural threads and then with spiral ones.

The supports are inspired after the way spiders build their webs.

 

Printing and first tests

Printing Time!

The printer is far form being finished, as a matter of fact; I have more questions now than just a couple of months ago. As a proof of concept The Bug answers some interesting questions regarding how we can make things, igniting ideas for future work. 

 Final Print (test3)

Final Print (test3)

Select Press:


References:

Chang, C., 2004. Rapid prototyping fabricated by UV resin spray nozzles. Rapid Prototyping Journal, 10 (2), 136-145
Lange, D. 2013. Image based one line drawing. Available online:  http://www.openprocessing.org/sketch/84552 [Accessed: 10/01/2013]
Oxman, N., Laucks, J.,Kayser, M., and Firstenberg, M. Robotically Controlled Fiber-based. Manufacturing as Case Study for Biomimetic Digital Fabrication.
Zschokke, S. 1996. Early stages of orb web construction in Araneus diadematus Clerck. REVUE SUISSE DE ZOOLOGIE, vo!. hors serie: 709-720; aoilt 1996