ROBOTIC 3D PRINTING OF LATTICE STRUCTURES

Lattice structure beams are optimized, printed,and analyzed for structural analysis.

 

Jasmine Kim 1, Daniel Marshall 2, and Caitlin Mueller 3

1 Department of Physics, Department of Mathematics, Southern Methodist University

2, 3 Department of Architecture and Planning, Massachusetts Institute of Technology

Date : June, 2016 - August, 2016 (MSRP)

 
 
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Why Lattice structures?

Lattice structures are known to be among the strongest materials per weight. However, previous scholarship upon lattices has only considered uniform structures. New digital fabrication technologies allow for irregular lattices which are even more optimized for strength to weight ratios.

 

What do we do?

To prevent the overuse of materials in construction, the MIT Digital Structures Group is researching the concept of digitally fabricated lattice structures. Using a Kuka Robotic Arm with a modified PLA (Polylatic-acid) extruder, we can print octahedral lattices, initially as small blocks that can be stress tested, and ultimately handle the weight of the human body. Although 3D printing may provide a new technological method for future architectural structuring, it currently faces geometric and stability issues to print perfect lattice form.

 

 

what's the process?

To overcome these challenges, the research focuses on computation, structural design, and force testing. After iterations of load testing and finite element analysis comparison, it is identified that three-point joint algorithm performs better than the one-point joint algorithm overall.

 
 

PHYsical vs. simulation

Physical three point bending test for a rectangular octahedral lattice structure

Physical three point bending test for a rectangular octahedral lattice structure

Three point bending simulation using Karamba tools for structural analysis (Yellow: Buckling, Red: Compression, Blue: Tension)

Three point bending simulation using Karamba tools for structural analysis (Yellow: Buckling, Red: Compression, Blue: Tension)

 
Left to right:  Caitlin Mueller  ( Faculty at Massachusetts Institute of Technology),  Jasmine Kim  (MS EDI 18' Northwestern University)

Left to right: Caitlin Mueller ( Faculty at Massachusetts Institute of Technology), Jasmine Kim (MS EDI 18' Northwestern University)

REsults of testings

 

When one-point node and three-point node printed specimens were compared, three-point nodes performed higher overall than the one-point nodes.The specimens hold up to 500 times its weight in a three-point bending test and 1000 times in pure compression. These results prove potentials of lattice structure printing for practical usage in the future. 

 

personal contribution

Quantitative Research

  • Analyze data from computational model and physical load testing

  • Data comparison for predicted and experimental values

Software Implementation

  • Use Rhino, Grasshopper, and Karamba for finite element analysis (Structural analysis using buckling factors)

 
 

Video 1. Printing Process | Thermal Imaging | Load Testing

 

MIT SUMMER RESEARCH PROGRAM

 

 Seeks to promote the value of graduate education; to improve the research enterprise through increased diversity

 
MSRP 2016 Cohorts

MSRP 2016 Cohorts