Elli Ehinger, a sophomore in chemical engineering, is participating in a summer Research Experience for Undergraduates (REU) program, designing a mobile air quality sensor to help researchers model air quality.

We ask Elli for her thoughts on her research and the REU program.


Elli Ehinger holding her air quality sensor.
REU student, Elli Ehinger, sets up a mobile air quality sensor with the aim of comparing particulate matter data.

Q: Tell me a little bit about your air quality research project.
A: The goal of this project is to design and test an inexpensive air quality sensor made from a Raspberry Pi with temperature, humidity, pressure, and particulate matter sensors added on. Eventually, these sensors could be installed on busses to map the air quality of a city in real time. This summer, I have been working on how to have the sensor send the data it collects in a way that is both inexpensive and easy to use. This is a key step to being able to model current air quality.

Q: How did you get interested in this area of research?
A: Coming into college, I did not know exactly what I wanted to study. I still don’t. However, I had broad ideas of things that interested me — mostly sustainability and helping others.

I have always been good at math and science, so naturally I was drawn to engineering. When I started looking for research positions, I read through all the faculty pages for the Civil and Environmental Engineering department. This was shortly after the forest fires in August so atmospheric research felt very relevant and important. I think this area will only become more important as time goes on. As is the case for many of our climate change challenges, finding ways to monitor and live with this air quality will be important. The trend of lengthening fire seasons only seems to indicate worsening air quality.

Q: Why did you decide to participate in the REU program?
A: I had been conducting research with Professor Walden since October 2020. I enjoyed the work and was looking to continue doing research over the summer. Professor Walden suggested that I apply to the Laboratory for Atmospheric Research (LAR) REU. I had just started working on this project and wanted to have the summer to dive in and explore it more without having other commitments like schoolwork. I also liked having an idea of what I would be working on and already being familiar with the project.

Q: What have you learned from working on the project?
A: I have gained a few skills that I think will help me in the future, the most valuable of them being a rudimentary understanding of writing Python code, being able to read a script, and understanding what it is trying to do. I have also learned how to work with a Raspberry Pi and have a better understanding of its capabilities.

I have also found ways to work around challenges. There have been many instances where I felt like I was in way over my head and would never be able to fully understand my work. Letting these roadblocks stop my project was not an option. My main strategy for dealing with the roadblocks was to make lists and break down bigger tasks into their components. Knowing that this system works for me is fantastic, and I will continue to work this way in the future.

Q: What are you most looking forward to with the return to in-person classes this fall?
A: I am looking forward to not having to deal with bad internet! More significantly I am excited to meet new people in classes and to studying in the library. Over the last year I realized how much of a luxury it was in high school and now to have places other than my room to study in. I am also excited for clubs being in person. I enjoyed clubs last year, but I found it very hard to participate because my internet was so bad that I might only hear two thirds of what was spoken. It will be fun to meet the people that I met over Zoom last year in person.