Mihaela Vlasea might have headed off to medical school after earning her Bachelor of Applied Science in mechatronics engineering degree at the University of Waterloo.
Instead, she chose to stay to push three-dimensional (3D) printing into new territory: Bone replacements that have the porosity and function of the real thing.
For thousands of Canadians facing surgery to deal with the pain of faulty joints, this holds the possibility of improved, lasting remedies.
“I could see where my technique would have an impact right away,’’ Vlasea says.
Researchers prefer the term “additive manufacturing” to describe any one of several processes that produce three-dimensional objects by fusing together material one tiny layer or strand at a time. Heat and organic or inorganic binders can all play a role in the process.
Focused light, often in the form of lasers, offers one source. Vlasea’s work involves ultraviolet light, an inorganic binder, and a compound called calcium polyphosphate.
Although it has been around for almost 27 years, additive manufacturing has only recently — over the last five years — drawn wide, wonderstruck attention in and out of the academic community.
Machines have become smaller, smarter and cheaper. The materials they currently use range across different types of metals, plastics and ceramics.
Researchers have stopped wondering whether they will ever make organs and other body parts using live cells as media.
Now, they ask, how well can they do it? Functional organs are just around the corner.
Although 3D printers differ in method, they have at least one thing in common: They like to read. Nothing gets done without somebody creating a computer-aided design (CAD) file that lays out the dimensions and features of the product.
“We’re getting some fantastic physical properties out of additive manufacturing,” says Ehsan Toyserkani, who runs Waterloo’s Multi-Scale Additive Manufacturing Laboratory (MSAM) located in Engineering 3. “The mechanical strength we are getting is much better — in some cases as much as 25 per cent improvement — over conventional manufacturing.”
Toyserkani’s lab, where Vlasea does much of her research, spins off patentable developments in additive manufacturing. By exploring “micro-scale additive manufacturing,” it has found a way to embed sensors into metallic objects as they are being printed.
In Ehsan Toyserkani’s Multi-Scale Additive Manufacturing Laboratory researchers, including Esmat Sheydaeian and Ahmad Basalah, explore the potential of 3D printing technology.
Waterloo researchers also developed a means of monitoring and sensing the process zone in laser direct metal fabrication, one form of 3D printing, to improve its repeatability, accuracy and reliability.
“At the moment, we have been recognized as the first university in Canada doing extensive research and development in additive manufacturing. Waterloo hopes to enable the next generation of additive manufacturing processes and advance the existing technologies for numerous applications through a holistic approach. Several universities, coast-to-coast, have recently started working on this area, so we expect to see multiple national collaborative projects,” says Toyserkani, an associate professor in the Department of Mechanical and Mechatronics Engineering in the Faculty of Engineering.
Plastic prototyping: Manifold destiny
Across Waterloo’s campuses, additive manufacturing has moved from the fringes of learning to the mainstream.
Toyserkani’s research team works with five machines it built from scratch or bought and modified. His team experiments with materials and methods in the emerging field of bioengineering. Vlasea's work since 2008 has earned her a BASc and a PhD in mechatronics engineering. She's now doing post-doctoral research in the Faculty of Engineering.
Elsewhere on campus, a group of students last year used laser sintering, a form of 3D printing, to fuse chocolate into three-dimensional objects.
But most of the additive manufacturing happening at Waterloo turns out parts and prototypes made of plastic.
Quick and inexpensive, a 3D-printing process known as fused deposition modelling offers students and faculty a means of rapidly giving shape to ideas rattling around in their heads.
“We’re able to design something in the evening and try it the next day,” says Thomas Abdallah, a second-year mechanical engineering student on the University of Waterloo Alternative Fuels Team. “Now we’re at the point where we can print iterations and have them work really well.”
The team printed an air-intake manifold to squeeze into the snug engine compartment of its modified car.
Peter Teertstra has been impressed with the innovation of students who come to the 3D Print Centre at the Sedra Student Print Design Centre in Engineering 5. Co-op employee Genie Kim, a first-year mechatronics student, helps clients refine their CAD files and pick the best plastics for their project.
Fused deposition modelling lays down filaments of heated plastic. Objects take shape over several hours or days, depending on complexity.
Still, it’s faster and cheaper than having a machine shop make a prototype in metal. Additive manufacturing takes some of the risk out of prototyping.
Men and women living in the Velocity Residence for student entrepreneurs don’t have to travel far to work out an idea in three dimensions. They can build prototypes on an in-house MakerBot printer, which uses fused deposition modelling. MakerBots are small enough for home use.
At the School of Architecture, in Cambridge, students have access to a MakerBot and a larger fused deposition printer.
“They’ll use 3D printing to solve design issues,” says Heinz Koller, manager of the school’s fabrication laboratory. “It’s often more effective to hand somebody a 3D model, as opposed to trying to explain a 2D sketch.”
One event more than any other widened the eyes of the Waterloo community to the potential of additive manufacturing.
In February 2013, the Sedra Student Design Centre in Engineering 5 formally opened its 3D Print Centre to introduce its star tenant — a Fortus 360mc printer.
A display case at the centre contains chess pieces, an IronMan mask and tools with moving parts — made of plastic by fused deposition in the Fortus. Available to all Waterloo students and faculty, the printer often runs around the clock to meet demand.
Additive manufacturing helps drive inventiveness, says Peter Teertstra, director of the Student Design Centre.
“It affects the way you design,” he says. “On paper, you can never completely visualize all the parts to see how they fit.”
Now students can spot flaws in function and quickly try again, he says.