A Swiss engineering graduate has created software that automatically transforms 3D images into Lego bricks and proposes a detailed plan for complex construction.
So far, creating arbitrary 3D models out of Lego has been mostly a matter of trial and error. In a paper recently published in Eurographics, Romain Testuz, a graduate of the Swiss Federal Institute of Technology in Lausanne, puts forward a program that creates precise construction plan for any elaborate 3D object, including the exact number and type of Lego bricks needed.
Instead of randomly trying what might work, Lego builders can simply follow the computer-generated building guidelines.
The Lego Group has previously presented this challenge to the scientific community to solve in 1998 and 2001. The recent study builds on previously designed approaches but takes them another step further.
“The first challenge was to find research that had been conducted on this subject and to understand what wasn’t working in pursuit of a better solution,” said Romain Testuz.
Previous programs focused mainly on disassembling 3D objects into smallest possible units that were subsequently substituted for larger bricks on a random basis. This approach has not always worked as the virtually-created bricks didn't represent the actual characteristics of the real building parts. “It’s at this stage that we find the strength or weaknesses of the object,” Testuz said. “If the bricks don’t fit, your actual model collapses.”
Instead of just disassembling objects into bricks, Testuz and his supervisor Yuliy Schwartzburg turned to graph theory to handle the stability and structural weakness of Lego-built structures. Each Lego brick in the model is thus represented by a red dot and each connection by a blue line. The programme assesses the stability of the structure based on the quality of the connections, or edges between particular bricks, and automatically proposes solutions to improve the most failure-prone sections.
By hollowing the model, the method also allows users to limit the number of bricks used and can even take into account the preferable colouring of the final structure. Based on available material - type and amount of Lego bricks - the programme can propose several construction solutions.
The authors explained that the Lego approach, enabling the construction of elaborate structures from simple standardised units, could represent a cheaper alternative for 3D model generation that wouldn't require using costly 3D printers and laser cutters.