MultiFab 3D prints a record 10 materials at once

Researchers at MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL) say that they have developed a 3D printer that can print an unprecedented 10 different materials at once by using 3D-scanning techniques that save time, energy, and money.

Delivering resolution at 40µm, the 'MultiFab' system is the first 3D printer to use 3D-scanning techniques from machine vision, which is said to offer two key advantages in accuracy and convenience over traditional 3D printing.

First, MultiFab can self-calibrate and self-correct, freeing users from having to do the fine-tuning themselves. For each layer of the design, the system scans and detects errors and then generates so-called 'correction masks'. This approach is claimed to allow the use of inexpensive hardware while ensuring print accuracy.

Secondly, MultiFab gives users the ability to embed complex components, such as circuits and sensors, directly onto the body of an object, meaning that it can produce a finished product, moving parts and all, simultaneously.

"The platform opens up new possibilities for manufacturing, giving researchers and hobbyists alike the power to create objects that have previously been difficult or even impossible to print," says Javier Ramos, a research engineer at CSAIL.

3D printers designed to fabricate multiple materials have traditionally been limited to three materials at a time, and can cost as much as $250,000 each. The CSAIL team claims that MultiFab was built using low-cost, off-the-shelf components that cost around $7,000.

There are many technical challenges to creating a printer like MultiFab: Different materials require different pressures and temperatures, so printing something complex usually involves printing the individual pieces separately, and then assembling them by hand.

But with MultiFab, users put the components into the platform and the printer does the rest. Cameras automatically scan the components' three-dimensional geometries and use that information to print other objects around them. For example, you can put a mobile phone into the printer, and program the system to print a case that is directly affixed onto the phone.

Rather than using extrusion technology, which can lead to low-quality finished items, MultiFab mixes microscopic droplets of photopolymers together that are then sent through inkjet printheads. This computationally intensive process, which involves crunching dozens of gigabytes of visual data, is said to be much more easily scaled to larger objects and multiple materials.

The researchers have used MultiFab to print everything from smartphone cases to LED lenses. They envision an array of applications in consumer electronics, microsensing, medical imaging, and telecommunications, among other things. They plan to also experiment with embedding motors and actuators that would make it possible to 3D print more advanced electronics, including robots.