MIT team develop multimaterial 3D printing platform to produce complex electric motors in a single step
Platform capable of printing functional electric machines using five materials and four extrusion tools, with results that rival conventionally manufactured devices
Researchers at the Massachusetts Institute of Technology (MIT) have developed a multimaterial extrusion 3D printing platform designed to fabricate complete electric machines in a single manufacturing step.
Their system uses four extruders, each capable of handling a different form of printable feedstock, including electrically conductive and magnetic materials. The nozzles switch as the machine builds a device layer by layer.
Most existing multimaterial extrusion systems are limited to two materials in the same form, such as filament or pellets. The MIT team retrofitted an existing printer with custom extruders and a novel control framework to bypass that limitation, and strategically placed sensors to ensure each nozzle moved with sufficient precision to prevent layer misalignment.
The electrically conductive materials, which come in ink form and print using a pressure-based extrusion process, presented particular integration challenges alongside standard heated-nozzle extruders.
“There were significant engineering challenges. We had to figure out how to marry together many different expressions of the same printing method — extrusion — seamlessly into one platform,” stated Luis Fernando Velásquez-García, a principal research scientist in MIT’s Microsystems Technology Laboratories and senior author of a paper describing the platform, published in Virtual and Physical Prototyping.
The team printed a functional electric linear motor in approximately three hours using five materials, at an estimated material cost of around $0.50 per device. The only post-processing step required was magnetizing the hard magnetic materials. The printed motor generated several times more actuation force than comparable linear motors that rely on hydraulic amplifiers.
“This is a great feat, but it is just the beginning. We have an opportunity to fundamentally change the way things are made by making hardware onsite in one step, rather than relying on a global supply chain. With this demonstration, we’ve shown that this is feasible,” said Velásquez-García.
The team plans to integrate the magnetization step into the printing process, demonstrate fully printed rotary motors, and expand the platform’s toolset to support monolithic fabrication of more complex electronic devices.
“Even though we are excited by this engine and its performance, we are equally inspired because this is just an example of so many other things to come that could dramatically change how electronics are manufactured,” Velásquez-García concluded.
