Think Inside the Block

Those with an engineering mindset may move on to bigger and better things over time, but they usually have a love for building blocks, like LEGO, from their youth that never fully fades. In a lot of ways, these bricks are the perfect prototyping platform — they can be taken apart and rebuilt time and again until everything is just right. Contrast that with 3D printing, laser cutting, and the other tools of the trade where each iteration of a design that is not quite perfect needs to be scrapped. Considering how many revisions go into a complex design, that leads to a lot of waste.

But alas, LEGO bricks are not big or sturdy enough to build large, weight-bearing structures. Furthermore, they are not easily integrated with the high-tech components, like microcontrollers and sensors, that we need to incorporate into many project designs. A new platform called the Voxel Invention Kit (VIK), which was recently developed by a team at MIT, promises to offer us something like grown-up LEGOs. These voxels are reconfigurable, sturdy building blocks with integrated electronics that could speed up prototyping while cutting down on waste.

Each VIK voxel is an aluminum cuboctahedral lattice that is optimized for ideal stiffness-to-weight properties. Cross-bracing further enhances the strength of each individual unit. To keep costs down, the faces of the voxels are not produced with a CNC machine as you might expect — instead each face is a 1.6mm-thick aluminum PCB. These can be produced for about 70 cents each in quantities of 250. Despite their lightweight construction, these blocks can support significant loads — one voxel alone can bear up to 228 kilograms, roughly the weight of an upright piano.

Two types of PCB faces have been produced: structural faces that route power and signals, and microcontroller faces that integrate processing units directly into the frame. Provisions have also been made for integrating traditional PCBs into the structure to accommodate additional functions. Snap-fit joints make the mechanical connections between voxels, while exposed pads at the edges are bridged with solder to make electrical connections.

To make VIK accessible to a wider audience, the MIT team developed a design tool that allows users to simulate their voxel-based structures before assembling them. This software includes Finite Element Analysis simulations, which help predict how a structure will respond to physical forces. By highlighting potential weak points in a design, users can adjust their models before even touching a physical voxel.

VIK’s reconfigurability makes it an ideal solution for industries that require rapid, cost-effective prototyping of large structures. Potential applications include theatrical stage design, where customizable, reusable set pieces could be built and rebuilt in a matter of hours. VIK could also prove useful in space exploration, where astronauts might need to construct and modify infrastructure on-demand.

With its combination of strength, adaptability, and integrated electronics, the Voxel Invention Kit might prove to be a significant leap forward in the area of rapid prototyping. By removing the constraints of traditional fabrication methods, voxels could transform the way we design and build interactive structures.