Researchers 3D print a working loudspeaker
Rather than buy a replacement part from a local hardware store, 3D printing offers up the opportunity to produce what you need at home, when you need it. But what if you have to replace a whole unit? If a project from Cornell University's Creative Machines Lab is any indication, such things may soon be possible. A research team has managed to 3D print the cone, coil and magnet of a loudspeaker, and then use it to throw out sounds from a digital audio player.
The work of mechanical engineering graduate students Apoorva Kiran and Rob MacCurdy, along with associate professor Hod Lipson, the project made use of Fab@Home Model I research printers originally co-developed by Lipson to first print off the plastic shell, flexible membrane and base. Then a silver ink conductive coil was printed inside the housing. Finally, with some development help from fellow student Samanvaya Srivastava, a strontium ferrite magnet was printed into the base. The whole unit was then heated to harden the metal components, before being connected to a digital audio recorder and power amp for a demo test.
Though this project involved two printers and a bit of manual assembly, the team points to a future where active integrated systems can be printed at home.
"We used two [printers], one for plastic and other for magnet and coil," Kiran tells Gizmag. "We could use one for all just that we did not have enough space on a single printer to accommodate plastic printing tool head and magnet/coil printing tool head at the same time. We put two parts together by hand and hook it to the audio source with a connecting wire. Typically for powering there is an amplifier."
Multi-national fabricators and manufacturers needn't worry about tumbling profits just yet, though, as many of today's 3D printers might struggle when handling the many different materials necessary for full system production.
MacCurdy told Gizmag that the team is still in the process of drafting a research paper for future publication. Meanwhile, the video below shows the whole 3D-printing and assembly process, and finishes with an audio output test.
"Sound quality of a speaker is judged mainly based on its frequency response," says Kiran when asked about audio output quality. "A typical speaker must have a flat frequency response in the range of 20 Hz to 20 KHz. We get a relatively flat frequency response, though not as good as commercial ones. The issue is energy efficiency. We have to use an amplifier to get a decent volume."
Source: Cornell Chronicle