Advanced Technology at East Tennessee State University
A Dimension 3D Printer helps students and
professors discover the power of the rapid redesign process at East
Tennessee State University.
Product design is a key aspect for those involved in applied research in the technology and geomatics department of East Tennessee State University (ETSU). Whether developing an automated bubble blowing apparatus that was tested in zero-G by NASA or creating an automotive air filter adapter, crafting innovative designs and continuously improving prototypes is a primary educational and research tool for ETSU. "We like to focus on the process when creating new products," said Bill Hemphill, associate professor at ETSU. "Having students make mistakes, redesign and rebuild is what education is all about."
Finding the Right System
In order to perfect the product development process, students and staff
needed a system that would quickly create durable models and work fast
enough to keep up with their redesign process. "We experienced problems
with models failing to withstand typical force applications. These
failures made it extremely difficult for students to create and
field-test their designs. We needed a system that could quickly produce
models with the ability to handle the appropriate forces," said
Hemphill.
The technology and geomatics department purchased a Dimension BST-fused deposition modeler (3D printer) after determining it would best meet the University's needs. The department looked at several entry-level printers from different manufacturers and the Dimension 3D printer rose to the top.
The Dimension 3D printer is a networked, desktop modeling system that builds functional 3D models with durable ABS plastic from the bottom up, one layer at a time. "Dimension's ABS plastic provided us with models capable of surviving our fit and function experiments, as well as maintaining momentum for a rapid redesign process," said Hemphill.
The Dimension 3D Printing Group is a business unit of Stratasys, Inc., based in Minneapolis, MN. Dimension 3D printers—which include the Elite, the Dimension 1200 Series and Dimension 768 Series—are networked, desktop modeling systems that provide CAD (computer-aided design) users with a fast, office-friendly, low-cost alternative for building functional 3D prints. Dimension 3D printers build accurate models layer by layer using durable ABS plastic, allowing users to not only evaluate design concepts, but test 3D prints for functionality, form and fit. As they have the first large format desktop 3D printer that sells for less than $30,000, Dimension incorporates many key features found in modeling systems that cost tens of thousands of dollars more.
Putting Dimension to the Test
The first project in which the Dimension BST played an integral role in
the R&D process was in the development of a prototype snap hook
assembly for the ETSU Division of Theater. Dr. Delbert Hall, a
certified theatrical flying effects director at ETSU and Hemphill, had
previously collaborated on a number of projects and Hall was looking
for a better snap hook.
Prior to purchasing the Dimension 3D printer, the solution path for a project such as this was idea to CAD model, to CNC code, to hard tooling and then to prototype parts—a very time consuming process. "We had just purchased the Dimension modeler when Delbert came with this new idea, so I jumped upon the opportunity to use a 3D printer for prototyping," said Hemphill.
With the newfound ability to model and fabricate prototypes quickly, just a few design iterations were required to develop a highly optimized solution, reducing the overall length of the snap hook assembly. Liberated from the tyranny of thinking in CNC code, the designers were able to build and test design ideas quickly and inexpensively. "The snap hook models we developed were strong enough for some rigorous testing of form, fit and function—even to the point that holes were tapped directly into the ABS to hold the set screws," said Hemphill. The Dimension 3D printer delivered the freedom to literally 'play' with the designs and brainstorm ideas based upon parts in hand. After testing four slightly different models, each incrementally better than the next, the designers made the leap to incorporate the wire rope thimble directly into the hook body. "This was my personal 'Eureka!' moment in understanding the promise of rapid prototyping. Three-dimensional modeling is not just about having parts. It's about participating in a process of design improvement, something the students can learn by being hands-on, active participants in," said Hemphill.
Using Its Full Potential
Since then, more faculty have incorporated the Dimension 3D printer
into their classes and research and more students have taken advantage
of the school's new machine. One student, Sheldon Davis, won an SME
student competition based upon the use of 3D modeling technology to
optimize end-of-arm tooling for robots. Other student projects included
a two-piece buckle for knapsacks, a small flashlight and an extension
arm for a robotic deburrer.
In one ongoing case, ESTU is creating a surgical simulator system designed for OB/GYN training for over a dozen different surgical scenarios. The Dimension system has become integral in the design process and testing for the simulator, aiding in everything from multipart simulated organ mold builds to fabricating structural members. The complex frame parts have to withstand surprisingly rigorous forces and have the ability to hold liquids. ESTU's ability to experiment with various interlocking seam models and tweak various aspects of the simulator allowed them to achieve a working seam design within three quick tests.
"The Dimension 3D printer has produced models capable of being tested in working environments against real forces, heat, water and even threading. Combining the durability of ABS with the power to immediately improve and repeatedly test models makes our 3D printer the quintessential problem solving tool for product design and development," said Hemphill.
Going forward, the technology and geometrics department is beginning to work with the geologists at the Gray Fossil Site. The site was discovered in May 2000 during road construction and is located near ETSU in the southern Appalachian Mountains of east Tennessee. The site has already yielded the remains of a pre-historic rhino and provides researchers with a rare opportunity to study the paleoecology of southern Appalachia. Hemphill and students are hoping to take the fossils found and replicate them using the Dimension system. This would allow geologists the opportunity to share their findings with other schools and museums without putting the real fossils at risk.
"We envision it being especially useful for incomplete skeletons. With the Dimension 3D printer we should be able to replicate the animal based upon mirrored specimens and parts created from parametric data from similar finds, something we've never been able to do before," said Hemphill.
After two years, the Dimension system has
become a vital educational and problem solving tool at ETSU. "We find
ourselves depending upon Dimension's innovative models every day," said
Hemphill. "The Dimension 3D printer has become a staple tool within our
department, and will be integral to the overall education of students
in our new product development curriculum."
