Researchers have invented a new 3D printer called the ‘replicator’ that can shape objects and transform product design just by using rays of light.
The new 3D printer takes only a few minutes to turn soft and sticky liquids into complex solid objects. The researchers said that the replicators can change the way products like eyeglass lenses and prosthetics are designed and manufactured.
The name ‘replicator’ has been inspired from the Start Trek device that used a replicator to create and recycle objects on demand.
“I think this is a route to being able to mass-customize objects even more, whether they are prosthetics or running shoes,” said Hayden Taylor, assistant professor of mechanical engineering at UC Berkeley and senior author of a paper describing the printer.
“The fact that you could take a metallic component or something from another manufacturing process and add on customizable geometry, I think that may change the way products are designed,” Taylor said.
Replicator is completely different from the most 3D printers that build-up 3D objects layer by layer. The problem with layer by layer approach is that they form a stair-step effect at the edges. Further, these printers generally can’t build flexible objects because the material would lose its shape at the time of printing. To form objects of certain shapes, these printers need supports.
The replicator 3D printer depends on viscous liquid. When this liquid comes in contact with a certain threshold of light, it will react and turn into solid. This can create well-crafted patterns of solid from the projects of light.
“Basically, you’ve got an off-the-shelf video projector, which I literally brought in from home, and then you plug it into a laptop and use it to project a series of computed images, while a motor turns a cylinder that has a 3D printing resin in it,” Taylor said.
“Obviously there are a lot of subtleties to it — how you formulate the resin, and, above all, how you compute the images that are going to be projected, but the barrier to creating a very simple version of this tool is not that high.”
The researchers have used the new printer to build a number of objects from a tiny model of Rodin’s ‘The Thinker’ statue to a customized jawbone model. The replicator can be used to create 3D objects up to four inches in diameter.
“This is the first case where we don’t need to build up custom 3D parts layer by layer,” said Brett Kelly, co-first author on the paper who completed the work while a graduate student working jointly at UC Berkeley and Lawrence Livermore National Laboratory. “It makes 3D printing truly three-dimensional.”
There are several advantages of replicator 3D printer as it doesn’t generate material waste. The uncured material can be used again.
A resin is used as the printing material which is made up of liquid polymers, photosensitive molecules and dissolved oxygen. According to Taylor, the light activates the photosensitive compound which depletes the oxygen. The resin turns from liquid to solid in the 3D regions where all the oxygen is used. The resin that doesn’t come into use can be recycled by heating it up in an oxygen atmosphere.
Image source: Berkeley