The first functional loudspeaker made in 3D

We have not finished hearing about objects made by 3D printers. Here's a pretty impressive illustration: the first loudspeaker made entirely from a 3D printer.

It's a team of students from theCornell University in the USA who, using various types of conductive inks, have created the whole package, seamlessly integrating plastic, conductive and magnetic parts, and ready for use as soon as it comes out of the printer. This project was led by mechanical engineering students Apoorva Kiran and Robert MacCurdy, who are working with Hod Lipson, an associate professor of mechanical and aerospace engineering and one of the leading innovators in 3D printing, and who is at the origin of the concept of 3D printer Fab@Homewhose plans and software are entirely open source, similar to what the RepRap project.

A real technological feat!

A loudspeaker is a relatively simple object: It consists of plastic for the housing, a conductive coil and a magnet. The challenge ahead is the design and precise materials that can be functionally co-manufactured.

But the team faced a number of technical challenges with conductive and magnetic inks. They had to be able to achieve the desired properties while at the same time being able to solidify at temperatures below 100°C. Silver nanoparticle ink, recently used to create electrical circuits, was used to make the coil.
The magnet, meanwhile, was printed from an ink made of strontium ferrite and a polymer. In both cases, the composition of the inks was designed so that the parts could adhere to the plastic frame. Apoorva Kiran adds that this high-precision chemistry must meet strict safety regulations regarding toxicity in order to be used safely by the general public.

https://www.youtube.com/watch?v=uEDWgwoW5

Hod Lipson explains that this first simple demonstration is only the "submerged part of the iceberg. And that it will take some time for consumers to adopt electronic printing in the home. Most printers cannot effectively handle multiple materials. It is also difficult to find materials that are compatible with each other - for example, conductive copper and plastic from the same printer require different temperatures for curing times. »

It takes about three hours to print a medium-sized loudspeaker, at a cost of about eight dollars (5.80 euros).

But what about the sound quality? Apoorva Kiran simply acknowledges that the frequency response is not of a very high level, but that design work will improve sound fidelity. Future tests will allow further development.

Historical origins

Photo: Left, the Vail register, the original telegraph machine that sent the first Morse code message in 1844. On the right, a replica that was printed in 3D in Hod Lipson's laboratory in 2009. 

This is not the first time a consumer electronic device has been printed in Lipson's lab. In 2009, Malone, a former member of the Matthew Alonso Laboratory, printed a replica of the famous antique telegraph receiver and recorder that Samuel Morse and Alfred Vail used to send the first Morse telegraph code in 1844.

Alonso, who was a student at the time, had decided to try printing an electromagnetic device, and Lipson naturally suggested the Vail register. It was one of the earliest applications of electromagnetism, and because Ezra Cornell had made his fortune in the telegraph industry, it became a centerpiece of research at Cornell University.

(Source: Cornell University - December 12, 2013)