Chopsticks & Glue: Japanese Researchers Unveil Unique 3D Printing Method

In a recent paper by researcher Hironori Yoshida and his colleagues, titled ‘Architecture-Scale Human-Assisted Additive Manufacturing,’ the authors outline how they physically tackled a combination of relevant subjects and issues, regarding the applications 3D printing can be delegated to in architecture, as well as how to make 3D printed objects of a more sizeable nature.

Yoshida and fellow authors Hironori Yoshida, Takeo Igarashi, Yusuke Obuchi, Yosuke Takami, Jun Sato, Mika Araki, Masaaki Miki, Kosuke Nagata (The University of Tokyo), Kazuhide Sakai, and Syunsuke Igarashi (of Shimizu Corporation), with their ideas presented at Siggraph2015, offer up some entirely new ideas regarding 3D printing materials and scale. The annual five-day conference, held for its 42nd year recently in Los Angeles, allows for innovators to convene for an interdisciplinary and educational forum regarding technology, graphics, apps, and more.

Attendees at the conference may have been more in the mood for large scale take out rather than banquet food after hearing what the researchers have learned to make–and what they use for material.

According to Yoshida and his team, the future of 3D printed architecture may lie in the process of using those wooden handheld utensils you wield like a pro for inhaling sashimi or an order of sizzling beef with broccoli sitting atop a mound of fried rice. While not addressed in this initial paper, it would seem that their concept also offers an amazing opportunity for recycling in the future via restaurants serving Asian fare. As it is, the researchers have created what they call a ‘human-machine’ cooperation where, operating in a user-friendly environment, multiple issues are dealt with, to include the following innovations:

• New and better materials
• A complex dispensing device
• Efficient 3D printing on a larger scale
• Comprehensive guidance for the whole process, especially construction of modules

With the use of chopsticks as ‘lumber,’ the researchers state that this material is prime for creating a porous structure with its aggregate construction.

“The straight shape is easy for storing and logistics,” state Yoshida and his team.

Using two different methods, jammed aggregation and stratified aggregation, the team has been able to come up with a clear and innovative method for elevating 3D printed architecture to the larger scale. Both methods, conceptualized through research and testing, employ the use of rows and rows of chopsticks which are accompanied by glue, and dispensed by an equally innovative device.

With jammed aggregation in 3D printing, the team had greater success. The chopsticks were dropped vertically, allowing for a quicker and easier process. Building oblique walls, they used the stratified and slanted approach. While successful and offering quality results, 3D printing with the stratified aggregation was higher maintenance and forced them to apply much greater precision in processes.

“The material was evaluated as a homogenous volume by the results from compression and bending tests,” reported the team.

Matters get more complex though upon consideration of and greater exploration into the dispensing systems. With the manual system:

• A bundle of sticks is dropped into the dispenser
• Sticks and glue are deposited by rollers
• The glue feeder applies wood glue to the rollers
• 3D printing operators are able to control angle at which sticks are dropped

With the stick blower system, a turbo blower and 20m length hose are used to manipulate the sticks into the vacuum where they are sent into a vortex and then handled accordingly.

Creating a guidance system that offers efficient and impressive workflow, the researchers included a depth camera for 3D scanning the geometry of the stick-made structure which is looked at comparatively in terms of the desired outcome, or ‘target geometry.’ Able to assess whether or not the current 3D printed structure is up to par, this process allows the researchers to judge whether it is ‘sufficient, insufficient, or excessive,’ and make changes where necessary before 3D printing of panels ensues.

After that, the process becomes even more fascinating–with the most logical and simple of ideas facilitating the building of a 3D printed pagoda. A color code is projected onto the structure. After that, a pre-calibrated projector system is set up over the structure with markers that are pre-set to help with the final build. Coordinates in a total of eight sets are ‘collected’ through the depth and projection map, allowing workers to verify positioning before they begin laying down their first layers of structure.

In making what was a full-scale pagoda structure, the researchers were able to 3D print and assemble panels inside. Outside, they were busy creating a solid foundation with the proper weights, reinforcements, and calibration markers offering a path for assembling the pre-fabricated panels. After three weeks of work, the pagoda was finished, resulting in an organic looking porous 3D printed shelter.

The impacts of being able to create something like this with such an easily obtained and inexpensive material have enormous potential for self-sustainability, especially in developing areas. Aside from that obvious potential, the structures could be used in more mainstream areas like campuses, built quickly for events, and placed in other areas where these types of smaller, simpler, and more affordable constructions would be an attractive idea for specific budget, space, and deadline requirements.

Have you considered the concept of using something like chopsticks or wood for creating 3D printed materials to make strong, small structures? Discuss your thoughts in the Large-Scale 3D Printed Chopsticks Pagoda forum thread over at 3DPB.com. Check out the video below detailing the process.