A cross-disciplinary team of faculty members from Clemson’s mechanical engineering and automotive engineering departments have come together for the research.

Srikanth Pilla, an assistant professor of automotive engineering, is the principal investigator on the project. The co-principal investigators are Melur “Ram” Ramasubramanian, D. W. Reynolds Distinguished Professor of Mechanical Engineering and department chair; Paul Venhovens, the BMW Endowed Chair in Automotive Systems Integration; and Gang Li, an associate professor of mechanical engineering.

Pilla said that as the team makes the door lighter, researchers would expect it to cost more because they are using more advanced materials. Researchers are mandated to keep the cost increase down to $5 for every pound of weight saved, but they expect the technologies they develop will ensure they can reach their targets.

“Of course, as we hit these weight and cost targets, we’re going to be careful to not compromise on functional or safety requirements,” Pilla said. “It’s possible we could exceed those requirements, even as we make the door lighter. We’re going to do this in collaboration with the University of Delaware and industry.”

Several public and private sources are providing funding for the research. The largest portion comes from the U.S. Department of Energy, which has announced it is contributing $2.25 million. Private industry contributed the rest.

Industrial collaborators include the businesses that would form the supply chain involved in manufacturing the composite doors that university researchers will develop, Pilla said.

“This project is particularly exciting because we have a commercialization plan,” Pilla said. “Our OEM partner has clearly expressed a strong interest to take full or partial technologies and put them into vehicles that will come in 2022 and beyond.”

Ramasubramanian said that having the majority of funding come from outside the federal government is a major success.

“This is the new model of funding by the federal government, where academia, industry and the federal government work as partners and share the benefits,” he said. “Everyone has skin in the game. For us to be successful in this at the lead is extremely significant. This sets the stage for future partnerships in composites technology.”

Major participants in the research include the automotive engineering department at the Clemson University International Center for Automotive Research (CU-ICAR), the Clemson mechanical engineering department, the University of Delaware Center for Composite Materials and more than 10 private industry partners, including material suppliers, machine builders, toolmakers and software developers.

While researchers are using the door as a model to investigate weight targets, the proposed technologies could also be applied to fabricate most of a vehicle’s structural, semi-structural and interior components, they said.

Researchers said the door would meet or exceed standards governing fit, function, safety, stiffness, crash performance, noise, vibration and harshness. The assembly would be recyclable when the vehicle hits the end of its life on the road, they said.

Researchers have proposed two designs for the door assembly and plan to pick one after six months of investigation.

Zoran Filipi, automotive engineering chair, said the research that Pilla and his team are doing will help connect CU-ICAR’s labs with the road.

“Not only will we help the auto industry meet a critical deadline, but we will also be educating the next generation of automotive engineers,” he said. “We’re creating the model to transform U.S. automotive engineering competitiveness.”

“This is an excellent example of how Clemson is integrating its main campus with its innovation campuses,” said Anand Gramopadhye, dean of the College of Engineering and Science. “It also embodies the college’s theme, ‘innovation through translation.’ ”

John W. Gillespie, director of the University of Delaware Center for Composite Materials (CCM), and assistant director Shridhar Yarlagadda issued a joint statement:

“Clemson and CCM are establishing a strong partnership to merge auto systems design with composites materials, design and manufacturing to lightweight composites door for high-volume production.”

One of the goals is to reduce the cost of making vehicles lighter, which improves their mileage and helps automotive companies meet federal fuel efficiency standards. But researchers said the technology could be used in a variety of industries, including home appliance manufacturing.

The technology could be ready for the manufacturing floor in as little as two years, Pilla said.

When some parts are made conventionally, one machine stamps sheet metal into the desired shape, and another machine creates polymer or composite parts. Then the pieces are bonded together with glue.

In hybrid single-shot manufacturing, it’s all done in one machine. The technology can be used in existing equipment, obviating the need for major capital investment, Pilla said.

The new method could reduce infrastructure costs and cycle time, while helping ensure that the pieces are mistake free and fit snugly together.

Pilla illustrated the work with a half-moon-shaped piece of polymer that was embedded in a rectangular piece of sheet metal.

“We are shooting the polymer into the sheet metal, and that is deforming the sheet metal,” he said. “While it’s deforming, it’s also bonding to the sheet metal. So, it’s one single operation.”

Farahani moved to Greenville from Tehran Polytechnic to work under Pilla as a Ph.D. student at the Clemson University International Center for Automotive Research.

“When I found this research topic in the literature, I thought, ‘This is going to be perfect for me,’” Farahani said. “My academic background is metal forming, but my experience is mostly on composite and plastic tool design. So with this subject, I can combine these two together.”

Pilla said the team’s approach to the research is unique.

“Maybe one or two research groups in the world have been working on this, but they are all looking at it from the metals side,” he said. “We actually flipped the problem, and we said, ‘This one people will do, and it’s easy to do because sheet metal has a pretty established methodology.’

“Also, my expertise is in polymers and composites, so it makes sense to investigate the problem by flipping it.”

As part of the research, Farahani built a “concept design tool,” and covered it with sensors that measure everything from temperature to pressure. He also created his own software that allows researchers to create a computer model of the machine’s process, also called a “digital twin.”

The digital twin coupled with artificial intelligence is playing a crucial role in teaching the machine to operate on its own.

For the tool to learn, it needs to make mistakes. But allowing the tool to run hundreds of cycles would be too expensive.

Instead, researchers have conducted a limited number of experiments with the machine. Now they are feeding data from the experiments into the machine’s digital twin, along with physics-based models that helps the machine understand its limitations.

“We are saying that science has limits, and these are the limits for you,” Pilla said of the message to the machine. “Then the machine will know what it’s capabilities are and accordingly it will try to learn by itself.”

The research helped Farahani secure his Ph.D. in automotive engineering in December. He is continuing this work as a postdoctoral researcher in Pilla’s lab to further refine the digital twin.

Researchers also plan to test the new technology at the Clemson Composites Center with the goal of making real components.