Taking inspiration from items such as mint leaves and cicadas, two students at STEM School Highlands Ranch are introducing a nature-based approach to address an ongoing nationwide problem: icy roads.
Today’s solutions to improve icy roads include anti-icing solutions such as salt or sand. But seventh graders Aarna Varre and Anirudh Rao argue those solutions are ineffective, expensive and harm the environment.
Over the course of a year, Varre and Rao studied biological surfaces that have natural hydrophobic and ice-resistant properties. With these, they invented concepts for improving roadways to help prevent crashes during rain and snowstorms.
“In Colorado, we’re surrounded by mountains, rivers and lakes, and we wanted to show the world how amazing Mother Nature is and how it has its own solution to problems that humans are still working out,” Varre said.
Varre and Rao are one of eight student teams who traveled to Washington, D.C. in early June to receive an award for their project in one of the world’s largest K-12 science competitions – the 33rd annual ExploraVision Competition.
Ranging from healthcare to transportation, students had to produce a system or a technology with the potential to solve a challenge in the world today and in the future. Their innovations were judged by a panel of scientists across various sectors of the government, such as NASA, the National Science Foundation and the National Institutes of Health.
“You can just have an idea, and that’s good enough for the future,” said Rao. “You can improve on it.”
Pure curiosity
It wasn’t a homework assignment or a class project that inspired Varre and Rao to look into the issue of solving dangerous icy roads. It was pure curiosity.
“We’re always driving and noticing how dangerous icy roads can be,” said Varre. “One day, we just thought maybe there could be a type of way to fix the solution.”
Rao added that instead of waiting for the opportunity to come to them, they would start making it happen.
The students spoke with the state and the U.S. Department of Transportation to learn about the different types of road materials, and the severe impacts icy roads can have.
According to the USDOT Federal Highway Administration, about 70% of the country’s roads are located in snowy regions, and nearly 1,840 deaths and 136,310 injuries occur each year as a result of snowy and icy roads.
Through their research, Varre and Rao learned that snow and ice reduce pavement friction and vehicle maneuverability, thus causing increased crash risk. They also learned that the de-icing solutions used today pose a high risk to wildlife.
“Road salts have environmental effects as the chemicals and microplastics in the runoff can contaminate drinking water, kill or endanger wildlife, increase soil erosion and damage private and public property,” Varre said.
One step closer to a solution
Varre and Rao found a unique way to increase friction on the road through a centuries-old practice called biomimicry.
Biomimicry is the practice of taking inspiration from nature to develop innovative solutions. One of the earliest mentions of the practice dates back to Leonardo da Vinci’s study of birds to design flying machines.
The students conducted a study of biological surfaces by looking at various flora and fauna species that have evolved over millions of years to have hydrophobic and ice-resistant surfaces.
Patterns from sources such as mint leaves, cicada wings, lotus leaves and Namib desert beetles were examined to determine the structures that were most effective at reducing ice adhesion and accelerating melting.
“We found that a combination of the mint leaf pattern at a 150-degree angle was perfect because barely any ice formed,” Varre said.
Varre and Rao then 3D printed these patterns to test the effectiveness of the patterns under controlled conditions like temperature and humidity levels.
They re-created the most effective patterns on a sample set of asphalt and put it through a freeze-thaw test to validate the anti- and de-icing properties before 3D printing a road surface embedded with the biometric pattern.
Using their parents’ vehicles, the sample pieces of road underwent testing to evaluate the skid resistance and moisture susceptibility – tests that are conducted by CDOT.
Rao said that with the continuing evolution of 3D printing and nano-manufacturing, their innovation could be possible. He is in the process of working with the City of Lone Tree and CDOT to conduct a real-world test of their patterns.
Varre and Rao’s coach and teacher, Sheetal Rajput, was not only impressed by their curiosity, but loved seeing her students think beyond themselves.
“It is a great example of how we can take this and connect it to different levels – not just science, but engineering, transportation, nanotechnology – and together, we can definitely see something like this, using it to make things better and safer for everyone,” Rajput said.