The last chair you purchased likely arrived fully assembled, but let’s be clear: It didn’t assemble itself. There’s only one chair in the world that can do that, and it’s way too small for you to sit on. This very special chair, standing upon a 15 cm by 15 cm footprint, is the work of Skylar Tibbits and his team at the Self-Assembly Lab at MIT.

You’ve seen Tibbits’ (and his researchers’) work before. This is the same lab that made these programmable materials and created this self-assembling aerial installation out of balloons. Crazy stuff. The lab's most recent project, Fluid Assembly Furniture, is an investigation into how structures might be able to autonomously assemble in uncontrolled environments like water.

In the video you see six white blocks thrown into a tank. Turbulence shooting through the water jostles them around until eventually, after a good bit of random interaction, you see the pieces hook together to form a miniature chair.

Viewed in time lapse, it looks easy enough, but getting materials to self-assemble isn't simple. Every variable—the size, weight and geometry of the individual pieces, the force of turbulence, the amount of water, etc.—impacts how efficiently the chair builds itself. In this rough prototype, the chair is made up of six components. Each is embedded with magnets and has an unique connection point that allows it to latch onto another piece. Think of it like a puzzle with the magnets acting as the attracting force. “At close proximity, each piece should easily connect with its corresponding component but never with another one,” explains Baily Zuniga, a student in the lab who led the research.

The way the pieces eventually find each other is mostly a result of trial and error—pieces floating next to each other until they find their perfect match. It’s hard to tell from the video, but it took seven hours for the chair to fully assemble itself. Not lightning fast, but an impressive starting point. “Finding a way to make the pieces more interchangeable would increase the probability of the pieces finding their matches,” says Zuniga. “Thus resulting in a faster assembly.”

Faster is good, but there’s a delicate balance between randomness and control at play in self-assembly. Exert too much control over the system and you’ll be stuck with a one-trick object. Allow too much randomness, and you lose the ability to dictate the final form at all. “This project is somewhere in the middle,” says Athina Papadopoulou, a researcher in Tibbits’ lab. The chair project is more controlled than, say, the lab’s work on fluid crystallization, where 350 submerged spheres aggregate together without a formal shape. Still, there’s an element of not quite being able to govern what happens in the tank.

In some ways, this is a good thing. Flexibility will allow an object to adapt, which could be a useful trait in situations where underwater infrastructure needs to self-repair, for instance. But in the context of assembling furniture or some other pre-determined design, efficiency is important. Right now, the team is gathering quantitative data on the project to get a better understanding of why certain materials and shapes work better than others. Eventually, the team plans to make a self-assembling chair that's large enough humans to sit in and show parallel assembly with hundreds of chairs coming together simultaneously, but hang tight Goldilocks—that's gonna take a lot more research and a much bigger tank.