Dirty, dark, and dangerous. That’s still how many people regard manufacturing today — as a grim business tethered to 19th-century production models.
Northwestern’s Jian Cao wants to upend that perception by transforming the processes and materials involved in creating a vast range of goods. She says that modern manufacturing, while remarkably diverse, increasingly draws on STEM disciplines — like chemistry, computer science, robotics, nanotechnology, and materials science — in ways that traditional factory workers decades ago could hardly imagine.
“I think of the new manufacturing as a kind of integration platform, one that includes a focus on being smart, sustainable, and safe,” says Cao, the Cardiss Collins Professor of Mechanical Engineering at Northwestern’s McCormick School. A renowned expert in cutting-edge manufacturing processes and systems, Cao is an associate vice president for research and director of the Northwestern Initiative for Manufacturing Science and Innovation (NIMSI), whose efforts advance cyber-physical distributed and personal manufacturing systems. Several other University Research Institutes and Centers, including NUANCE, CIERA and the MRC, also report to her.
Just about anything we touch must be manufactured, Cao says. In recent years, manufacturing has even extended into terrain once thought the realm of science fiction: the cellular “factories” of synthetic biology, for example, or efforts involved in tissue engineering. Such work requires extensive interdisciplinary collaboration. That’s a trend Cao sees informing modern manufacturing overall as diverse stakeholders — from academia, industry, government, and the public — look to increase efficiency, quality, and customization while reducing waste and energy investment to create greener manufacturing.
The environmental issue is nontrivial, even when considering just a subset of all materials: According to World Wildlife Fund and Ocean Conservancy, 150 million metric tons of plastic pollute Earth’s oceans, with millions more being added annually. Then there’s all the food and beverage cans that add up to staggering numbers: Cao says some 375 billion cans are produced each year. A lot of those get recycled, but given the scale of that manufacturing, even very small process improvements can translate into huge economic and environmental benefits.
That’s why Cao’s approach to manufacturing is holistic and considers factors like reduction of raw materials. In fact, she says the most significant energy cost goes into making those materials, so if researchers like Cao can help create more readily recyclable materials, and with fewer ingredients, people and the planet win.
Cao’s research at NIMSI and McCormick’s Advanced Manufacturing Processes Laboratory (AMPL) is focused on advancing such possibilities. Among these investigations is National Science Foundation-funded work exploring the “cyber-physical” data structure — the foundation of a next-generation manufacturing platform — and rapid dieless forming technology, a new approach that can reduce time, cost, and energy in flexible sheet metal forming.
“With dieless forming, you don’t need to make a whole set of a mold, which is often constructed from hard steel with a lot of energy going into its manufacture,” Cao says. The dieless method, while slower than conventional processes and therefore more suited to low-volume production — can save huge amounts of energy: in global CO2 terms, Cao estimates the savings could be equivalent to the annual emissions of 300,000 mid-size cars.
Local and Global Integration
Cao sees manufacturing developing in ways that draw upon a distributed model — local level connections — but integrated with a global network to ensure quality control and certification. This model is informed by technological advances (think additive manufacturing methods like 3D printing and dieless forming) that will require a new approach to workforce training. She cites a 2018 Deloitte report that predicts a need for 4.6 million US manufacturing jobs over the next decade, although due to a skills gap only 2.2 million of those positions may be filled.
“STEM education is very much needed,” Cao says. “Manufacturing involves materials science, chemistry, and many different disciplines, in addition to mechanical engineering. It’s not just moving the assembly line: You need to know programming and have a heart for the well-being of people and the environment.”
Cao says that some nations, including Germany and South Korea, have taken steps to make manufacturing careers more attractive to young people and to educate them for these opportunities. In comparison, she says the United States is lagging, though she notes broad bipartisan political support for driving manufacturing innovation. That support is largely anchored by the “multiplier effect,” the potential economic impact that manufacturing brings: every dollar invested into manufacturing, Cao says, yields about $1.33 in output from other sectors. The total manufacturing value in an automobile, for example, includes assembly, but also an array of other inputs, from materials (glass, rubber, etc.) to shipping, marketing, financing, and more.
As a teacher and mentor, Cao is committed to strengthening the future manufacturing workforce — and to increasing the diversity of a traditionally male-dominated domain. “I am very much pushing for more inclusion in manufacturing,” she says. “By helping encourage and educate more women to join this field, we bring new ideas, perspectives, and talent into science and industry. At the same time, we cultivate greater equality and opportunity in society.”
Among those benefiting from Cao’s mentorship is Marisa Bisram, a first-year doctoral student in mechanical engineering. She says that Cao’s guidance and resources have proven valuable in the classroom and laboratory, where Bisram researches composite materials modelling. “Professor Cao’s promotion of diversity has helped to create a lab environment with different backgrounds and interests that support one another,” she says, noting the lab’s potential to advance manufacturing. “Modelling includes design optimization, which the composites field has previously relied on experimental results to perform. Design optimization through modelling will reduce the costs and time required in producing a composite part.”
From ‘Simple’ to Complex, and Back Again
Cao’s fundamental research contributions have earned her numerous distinctions, including being named a 2019 Vannevar Bush Faculty Fellow by the US Department of Defense and elected a 2018 fellow of the American Association for the Advancement of Science. In 2016, she was the first woman to earn the Frederick W. Taylor Research Medal, the highest honor given by SME for research excellence in the manufacturing field.
The Shanghai native would go on earn her undergraduate degree in materials science and engineering from Shanghai JiaoTong University and a doctorate in mechanical engineering from MIT, and her early experiences growing up in China offer some insight into this later academic success.
The daughter of a chemical (mother) and electric engineer (father), Cao recalls having relatively few toys as a child. But her favorite was a modest construction set that allowed her to combine fundamental pieces to create various things. “It was a kind of puzzle that I loved,” says Cao. “You could take these pieces and create a tractor, a car, and other things all from this one set. Even then I was trying to put things together.”
Cao says the Chinese character that forms her first name is relatively unusual and translates into “simple,” a choice she attributes to her mother wanting to avoid overly complicating the process. This personal biographical detail has proven a sort of research lens for Cao as she thinks about manufacturing and design: It’s not easy to make products or processes simple, and yet reducing this complexity or at least making it invisible for the end user is essential.
“You may start with a simple idea, then it becomes more complex as you develop it to have more functionalities, but eventually you also need to make it simple again [in the interface] for people to use it,” says Cao.
Unlike some other fields — physics and chemistry that are rooted in the Periodic Table — manufacturing lacks such a foundation and so its processes tend to be more ad hoc, says Cao. And if a process works, manufacturers may be reluctant to change how they operate. Also working against innovative aspirations are sunk costs, notably infrastructure — such as in the US extractive industries or its rail or communications systems.
“One reason China has developed so quickly is because there wasn’t that infrastructure already there,” says Cao. “That meant the nation could kind of jump forward and benefit from the latest technology. There’s a reason why the high-speed train was developed in Asia, while here we have the old Amtrak.”
Cao says she is excited by manufacturing’s future, which will include the “grand challenge” of reducing complexity and heterogeneity in manufacturing to create the possibility of a more integrated foundation — even if it’s unlikely ever to have the Periodic Table’s elegance.
“Smart, sustainable, and safe,” Cao says, keeping this framework before her as research inspiration. But she knows that for all its potential advantages, the new manufacturing’s strengths can produce new vulnerabilities that will require attention, too: “When you think about all those cyber-physical machines being connected, that’s also a cybersecurity issue.”