‘Sewing’ with molten glass and maths

Media caption3D printing meets the maths of dribbling fluids

US researchers have developed what they call a “molten glass sewing machine” by combining 3D printing of glass with a mathematical model of how a liquid thread forms different types of loop.

When the nozzle releasing a stream of molten glass is raised above a certain level, that thread begins to wobble.

It traces out waves or loops – which the team found could be controlled by adjusting the speed of the nozzle.

Those shapes then become the building blocks for intricate, 3D objects.

Engineers at the Massachusetts Institute of Technology pioneered a method for glass 3D printing in 2015. They then started to work with mathematician Pierre-Thomas Brun, who has studied the fluid dynamics of liquid “ropes”.

The results are documented in a video, which the team presented in the American Physical Society’s “Gallery of Fluid Motion” in November.

Image copyright
Pierre-Thomas Brun

Image caption

Tight loops like this are difficult to create with movements of the nozzle

It all started with a collaboration between two labs at MIT, Dr Brun told the BBC – one specialising in glass and the other in “mediated matter“.

Runny honey

“Normally when you 3D print, the nozzle is very close to the piece that you’re printing – that’s the conventional method. But what they started working with was having a large offset.

“And in that case, instead of having a thread that falls down and moves straight, you can create coil-like patterns like honey on toast.”

That coiling process, as it happens, is exactly what Dr Brun studied during his PhD.

Image copyright
Pierre-Thomas Brun

Image caption

The wobbling of the glass thread can produce different repeating patterns

“I came up with a reduced model that explained the dynamics of these things,” he said. “So I have a way to rationalise the patterns they observed, and we started working together in order to create some structures that take those patterns as building blocks.”

What Next?

Recent Articles

Leave a Reply

You must be Logged in to post comment.