Researchers Study Self-Assembly with 3D Printed Bricks, Hoping to Eliminate Factory Assembly Lines

Bricks have been used for thousands of years, with masonry as an art practiced by experienced souls, many of whom may be surprised to hear that a new study shows that with high-frequency vibration, bricks are actually able to morph into larger 3D objects.

The long-term impact for this discovery could mean less work available at the factory assembly line, as well as presenting numerous positive impacts in sectors such as construction.

Previously not a concept thought to apply to other dimensions due to a lack of specific algorithm programming, researchers from the Institute for Nanotechnology and Advanced Materials at Bar-Ilan University in Israel, led by Dr. Ido Bachelet, have now developed such a system and are indeed able to program materials into self-assembly.

What is self-assembly, and why are we bothering with it? A convenient mechanism exhibited by nature, we aim to re-create it as often as possible in other areas through information driven routes that are able to offer greater affordability and streamlining for numerous practices–with manufacturing as a case in point. This is discussed at length in a new research paper, ‘Meshing complex macro-scale objects into self-assembling bricks,’ just published by Adar Hacohen, Iddo Hanniel, Yasha Nikulshin, Shuki Wolfus, Almogit Abu-Horowitz, and Ido Bachelet.

“Self-assembly and self-organization are among the most peculiar, puzzling aspects of life,” state the researchers astutely at the beginning of their paper. “They occur at all scales: proteins, viruses, living cells, multicellular organisms, and swarms or societies of multicellular organisms. All these systems are comprised of interacting discrete parts that are attracted to each other in defined ways, leading to the formation of a global structure or pattern.”

They bring to light the new algorithm that can program self-assembly on the macro scale, using the unlikely, dense subject of bricks as their example–on a molecular level. Inspired by scaffolded DNA origami, which has been responsible for the fabrication of numerous nanoscale shapes, the researchers challenged themselves to program self-assembly in “solid, complex, asymmetric objects in 3D.”

In their project, the researchers 3D printed batches of bricks for their work on a Stratasys/Object Eden 250 3D printer using either VeroWhite or DurusWhite as printing materials. Supports were used and then removed, after which Neodymium-Iron disc magnets were glued to the 3D printed bricks. Set up in pairs, the fabricated bricks were given complementary faces. Eighteen tetrahedral bricks were placed in a large 3D cylinder and manipulated for self-assembly with a Multitron orbital shaker with speed control ranging up to 400 rpm.

“Assembly rules are encoded by topographic cues imprinted on brick faces while attraction between bricks is provided by embedded magnets,” the researchers said in their paper. “The bricks can then be mixed in a container and agitated, leading to properly assembled objects at high yields and zero errors.”

While so many differences from scaffolded DNA origami were built into the research project, many surprising similarities were discovered even though the DNA origami does not depend on algorithms for self-assembly. For one, although they delegated long periods of time for self-assembly, they discovered it took only seconds to complete; also, the brick self-assembly showed reliance on concentration of volume just as in the DNA origami.

“When the area was too large, brick assembly was inefficient and often did not take place at all,” state the researchers. “This could be solved by introducing ‘solvent’ bricks – inert, magnet-free bricks that do not participate in the assembly itself, but contribute to assembly by colliding and fixing incorrect assemblies. This concept can be extended as a general principle in future systems.”

Each experiment was repeated ten times. While previously a two-brick assembly did take less than a minute to self-assemble, the 18-piece took over two hours. Both audio and video were recorded and then the data was stored for analysis to be assessed by MATLAB.

“Improved designs inspired by our system could lead to successful implementation of self-assembly at the macro-scale, allowing rapid, on-demand fabrication of objects without the need for assembly lines,” stated the researchers.

Hamza Bendemra, a research engineer at Australian National University who was not involved in the study, found the research ‘remarkable,’ but he remains somewhat skeptical until more research can be done.

“The components are subject to high vibrations and collide over and over again until they fit in the right combination,” said Bendemra. “It would be a challenge to implement such a method with materials with low strength and poor impact tolerance without causing damage.”

While the conceptual implications certainly have great potential in terms of construction, manufacturing, and progressive new ways to package larger and smaller items, it remains to be seen how the self-assembly would work in a fashion where everything was not topographically designed to lock in, according to Bendemra.

Indeed, the next step in this research is to experiment with both magnets and adhesives for keeping all the pieces together. The hope is that this could lead to more efficient manufacturing practices, cutting out time on the factory line. The bottom line could be seriously cut if the pieces were able to ‘assemble themselves.’

Discuss your thoughts on this self-assembly concept in the 3D Printed Bricks forum thread over at 3DPB.com.