Mechanical engineering team creates multimaterial 3-D printer
By combining several additive manufacturing technologies into a single desktop unit, four recent Virginia Tech graduates have created a new way to manufacture complex, multimaterial products.
The device, known as the Dream Machine, took second place in a manufacturing design competition sponsored by the American Society of Mechanical Engineers.
Their submission to the Manufacturing Science and Engineering Conference was based on their senior design project, which aimed to revolutionize 3-D printing by allowing users to print multiple materials in a single build using multiple types of deposition tools.
According to Chris Williams, associate professor and John R. Jones III Faculty Fellow in mechanical engineering, director of the DREAMS lab, and the students’ faculty advisor for the project, the dream of additive manufacturing has always been to create end-use products. “To deliver on this promise, however, requires a system able to deposit multiple materials in a single build.”
The Dream Machine advances additive manufacturing (AM) by tackling the lack of integration among multiple AM technologies.
“There are many ways to print things, but at the end of the day we’re still stacking layers to create an item,” said Danny Rau, a 2017 mechanical engineering graduate who is staying at Virginia Tech as a graduate student to continue his 3-D printing studies in the DREAMS lab. The team behind the Dream Machine has filed a provisional patent application for the device.
“Bringing all these AM technologies into a single system is a novel concept,” Rau said.
The people the team have met with have been impressed by having all these technologies together creating complex parts that can’t be made by any other manufacturing technology. The AM technologies the team worked with for their product were filament extrusion, paste extrusion, vat photopolymerization, and binder jetting.
Despite the ability to simultaneously print with multiple technologies, not all formats work with each other. For instance, binder jetting only works in conjunction with paste and filament extrusion. However, most formats work with a majority of the other print types; for example, the machine can use paste extrusion to selectively deposit conductive ink into a high temperature epoxy part that is printed using vat photopolymerization.
Aside from the multiple printing types, the Dream Machine also features a method of modular construction that will allow it to continue to grow.
“The machine is more than just the print heads,” said Grady Wagner, a 2017 mechanical engineering graduate who began work at Space-X as an additive manufacturing engineer in July. “The build plate is also important. For instance, for light-based printing, the build plate can’t be reflective, but for plastic based materials, it needs to be heated. We’ve developed a modular platform where the user can change the size of the build plates, which allows for printing large parts and enabling researchers to work with small batches of experimental materials. In addition, the modular nature of the printer allows new print technologies to be incorporated as they become available.”
“We’re the pioneers of this technology, and that feels pretty good to say,” Rau said.
In addition to Rau and Wagner, the Dream Machine team includes:
Lindsey Bass, who will continue graduate studies on 3-D printing new materials in the DREAMS lab;
Mitchell Wolf and David Wolf, who work for Northrup Grumman;
Scott Ziv, who works for Naval Sea Systems Command.
Written by Rosaire Bushey