Students design autonomous robot to harvest microplastics from sand

In January 2019, first-year student Grace Robertson was involved in a beach cleanup, when she noticed tiny pieces of plastic in the sand that were too small to pick up and tended to break into smaller pieces. She started doing research and found out that these plastic bits, called microplastics, are in the air we breathe, the fish we eat and the water we drink.

“I knew we had to do something about this,” Robertson says.

She embarked on a project to build a robot to help cull the microplastics from beach sand. Now a sophomore studying aerospace engineering at Embry-Riddle, Robertson says her goal is to prevent these particles from “ending up back in the ocean and consumed by wildlife, in freshwater systems or in the atmosphere.”

According to a February 2019 issue of the journal TrAC Trends in Analytical Chemistry, microplastics “tend to accumulate and move through living organisms, inducing a variety of biological effects,” such as disturbances in metabolism, DNA, immunity and neurological function.

Supported by an Ignite Initiative grant from the Embry-Riddle Office of Undergraduate Research, Robertson is the general team lead on the project. She directs the electrical team and three other undergraduates, Emma Bucey, Jackson Schuler and Matt Liepke, who head up the logistics, design and software teams, respectively.

Using a GPS system, lidar obstacle avoidance and a technique called geofencing, the robot they’re developing will comb through dry sand one to three inches deep in a prescribed area, utilizing an induced electrical charge to attract the microplastics and gather them.

A secondary part of the project research involves developing a technology to use the collected microplastics. As Robertson points out, “If we take the microplastics out of the sand but throw them into the landfill, they will wind up back in the water.”

The research team is looking at technologies employed by such organizations as TechniSoil and UNICEF that use plastic bricks to build houses in developing countries. Another concept they’re considering involves repurposing the harvested microplastics to produce filament for 3D printing.

“This project has impacted my life way more than I could have ever thought,” Robertson says. “It’s taught me about sustainability and about how people learn, and how to be on a team.”