Tag Archives: replicator

We are one step closer to the first replicator

Scientists have developed and tested a 3D printing technique that quickly creates entire objects as a unit, rather than building them by layers.

Here’s how it works. First, the researchers use a computer-controlled digital light projector to cast a series of 2D images through a rotating vial containing a photosensitive gel. As the vial rotates, photons entering from different angles meet at selected spots in the gel. Where they meet, their combined energy solidifies the gel. Where that meetup doesn’t occur, the photons simply pass through without altering the photosensitive material.

The approach is fast, able to create complex objects, such as a centimeter-size copy of Rodin’s famous sculpture of The Thinker in just minutes, the researchers report today in Science. It can also make 3D plastic parts around existing objects, such as a plastic handle around a metallic screwdriver shaft. The approach could also be useful for encapsulating sensitive electronics, the authors write.

If you go to the supplementary material for their paper, you can watch several videos showing this process at work, creating both the Thinker as well as a ball in a cage.

I think I have reported on this process previously, but this new paper shows a significant advance. Nonetheless, this engineering here is still very preliminary.


New method to 3D print entire objects simultaneously, without layering

Life imitates science fiction: Engineers at Lawrence Livermore Lab have developed a new 3D method that creates entire objects in one piece instead of building them up with layering.

Developed by LLNL in collaboration with UC Berkeley, the University of Rochester, and MIT, volumetric printing replaces layering with a process that creates the entire object simultaneously. It does this by using three overlapping lasers beamed in a hologram-like pattern into a transparent tank filled with photosetting plastic resin. A short exposure by a single beam isn’t enough to cure the resin in a short time, but combining three lasers can induce curing in about ten seconds. After the object is formed, the excess resin is then drained off to reveal the complete unit.

“The fact that you can do fully 3D parts all in one step really does overcome an important problem in additive manufacturing,” says LLNL researcher Maxim Shusteff. “We’re trying to print a 3D shape all at the same time. The real aim of this paper was to ask, ‘Can we make arbitrary 3D shapes all at once, instead of putting the parts together gradually layer by layer?’ It turns out we can.”

Volumetric printing is not only faster, but eliminates the need for temporary support structures, is more flexible, and provides more geometric flexibility. So far, it’s been used to create squares, beams, planes, struts at arbitrary angles, lattices, and complex, curved objects.

The process still has problems, as the article describes. Nonetheless, this is just one more step in the invention process that is making a Star Trek replicator possible.

Hat tip reader Mike Buford.