Smarter 3D Printers: Improving Precision, Speed and Reliability at Low Cost

Scale models of US Capitol printed without vibration compensation (Top) and with vibration compensation (Bottom), leading to significant reductions in print time without sacrificing print quality.
Scale models of US Capitol printed without vibration compensation (Top) and with vibration compensation (Bottom), leading to significant reductions in print time without sacrificing print quality.

ME Associate Professor Chinedum Okwudire’s Smart and Sustainable Automation Research Laboratory develops solutions to enable automated systems, such as industrial manufacturing and vehicle automation systems, to do more with less so users face fewer tradeoffs between precision, throughput, energy efficiency and cost.

Much of the lab’s research leverages the synergies gained through mechatronics, the integration of mechanical disciplines, electronics, controls and computers. Recently the group has begun applying the same principles it uses in industrial systems to consumer-grade, desktop 3D printers.

“Some people think of these printers as toys, but they have a lot of educational and commercial uses; they’re not ‘just for fun,’” Okwudire said.

Adoption of consumer-grade printers, typically priced below $5,000, has been rapid. Over 278,000 units were sold worldwide in 2015, a 74% increase over the previous year, according to the 2016 Wohler’s Report. But it hasn’t reached its full potential.

In part that’s because, at the consumer price point, users must contend with issues related to motion-induced vibration. Consumer printers tend to be constructed with light and flexible mechanical parts, which can lead to excessive vibration as the print head moves. This, in turn, affects the precision, speed, reliability and appearance of the printed part.

Okwudire’s lab is applying its expertise in reducing vibration in engineered systems to develop new knowledge and automation solutions that address these challenges— while keeping costs down.

“Low cost is the ‘secret sauce’ to these machines, so while the technologies exist to reduce vibration in high-end, industrial printers, integrating them into consumer models would put them financially out of reach of the ordinary individual,” he said.

Okwudire and his research team are developing a software compensation technique called filtered B-splines (FBS) that uses a priori knowledge of the printer’s dynamics to mitigate vibration problems, allowing it to print faster without inducing errors. The software in effect predicts which user commands cause vibration and compensates for them proactively.

“Software compensation is not a new technique, but the challenge is how to employ it in a way that’s effective, robust and versatile,” he said.

The FBS technique is showing great promise in experiments, cutting print time significantly, while running at low computational cost and without any sacrifice in quality.

“The great thing about using software compensation is that it is, in a sense, free,” Okwudire said.

In collaboration with ME Professor Emeritus Galip Ulsoy, Okwudire’s team is simultaneously working to gain a deeper theoretical understanding of the FBS technique, with the goal to further improve its effectiveness, versatility and robustness. The work includes refining the technique to better accommodate uncertainty.

“We’re going deep into the math and fundamentals to better understand FBS and how to apply it even more effectively,” said Okwudire, who is planning to partner with desktop 3D printer manufacturers to integrate the software into their products.

His lab also is working with experts in artificial intelligence and complex systems to create technologies to enable desktop 3D printers to gather “big data” from outside sources, including other printers and their users. The goal is for each printer to learn from the collected information to improve performance, reliability and ease of use.

These intelligent 3D printers will also be designed with architectures that allow their functionalities to be customized and enhanced through hardware and software apps, much like smartphones can be. In Okwudire’s vision, the apps come not only from manufacturers but from end users and hobbyists, who are key to furthering adoption.

“What most appeals to me about desktop 3D printing is that it’s a grass-roots and, no pun intended, bottom-up technology,” he said. “So many ideas come from the broad base of enthusiastic users, which creates an incredible opportunity: to make 3D printers as versatile and easy to use as today’s smartphones.”

Okwudire has won a spate of awards for his research and teaching, including the 2016 Young Investigator Award from the International Symposium on Flexible Automation, the Outstanding Young Manufacturing Engineer Award from the Society of Manufacturing Engineers, the Ralph Teetor Educational Award from SAE International and, in 2017, an ME Department Achievement Award and the MLK Spirit Award.

Related professors