Undergrad uses LEGOs to conduct research from home

This past academic year, the pandemic brought numerous challenges into everyday life at MechSE and across campus, but students and faculty discovered ways to work around them to continue conducting their innovative research.

One creative example of this comes from Christopher Metellus, a rising senior studying mechanical engineering, During the Fall 2020 semester, he worked as an undergraduate research assistant with Professor Arend van der Zande running various experiments. However, due to COVID-19 restrictions, undergraduate students were not allowed into research laboratories. So, to participate in the research, Metellus designed his own creative testing methods—one of which utilized LEGOs.

The idea for the experiment came from ME370 Mechanical Design, a course which van der Zande taught, and Mettelus took. “During the pandemic, we had to completely re-think many of our hands-on labs to allow students to perform them at home,” said van der Zande. “One of the new labs required students to use cell phone cameras and free tracking software to measure the motion of mechanical four-bar linkages built using household items. Chris had the brilliant idea of modifying the capabilities of the lab to allow him to do research experiments at home using LEGOs.”

“I think it came a bit from what I was doing in ME 370, along with the fact that this is my hobby: building things from my imagination and seeing what I can make,” said Metellus.

For van der Zande’s lab, Mettelus was tasked with measuring the Young’s Modulus (stiffness) of a polydimethylsiloxane (PDMS) substrate. The Young’s Modulus of a material describes a relationship between the force exerted on a material and how much it deforms, and the lab needed these values to design their systems. To measure the force, Metellus used the weight of water in a cup that was clipped to the substrate using binder clips. The substrate was clipped to the top of the stand as well. He added force by adding tablespoons of water to the cup, which weighed down the PDMS substrate. Using his phone camera, Metellus took pictures of the stretched substrate and measured the changes in length between dots he drew in specific locations. The LEGO stand allowed him to place the substrate and his phone in the same spot every time, allowing for precise measurements. Metellus then used a software called ImageJ to analyze the pictures and measure the change in length by converting pixels in the picture to centimeters.

“What I love about this project was that it demonstrated that it doesn’t require thousands of dollars of specialized equipment to do good science,” said van der Zande. “Actually, the tools in our pockets like cell phone cameras are capable of pretty amazing things with a little creative design thinking.”

One of the projects the van der Zande group is working on is engineering stretchable electronics from crumpled nanomaterial films and having accurate material properties such as the Young’s Modulus are key to this work. Going forward, the Young’s Modulus value Mettelus experimentally found is being used as inputs to design how these nanosystems deform. Mettelus will be a co-author on a paper, currently in preparation, which utilizes his measured values.

Metellus took an interest in van der Zande’s work after realizing its potential to affect everyday life. “This one would be applicable towards modeling human skin and how that can react to different types of movements. I'm hoping to have my research contribute to that area of expertise,” he said.