Sustainable material use in assistive devices (BME 460)

For the past 17 years, I’ve taught a class for seniors in biomedical engineering, where they design devices to assist people with disabilities (BME460). It’s a service-learning class and meets the students’ design requirement for the major. The students build projects for clients with disabilities in the local community and deliver them at the end of the semester.

I’m also a farmer, with a small sustainable farm that includes pick-your-own blueberries and blackberries and a custom-order CSA for a number of local families.  Over the years, I’ve wondered how to include sustainability in my class, but I hadn’t previously devised how to do it formally and in a way that wouldn’t be too much of a burden on the students. When I heard about the Trillium workshop, I decided to do it with the hope that I’d be inspired to find a way to add a dose of sustainability to BME 460.

This year, we had a guest lecture about sustainability, an assignment to research sustainability trade-offs of project materials, a focus on reusing or recycling materials in the lab, and some organized carpooling. I felt that the students’ general awareness of sustainability was heightened.

Early in the semester, before students had purchased many materials for their projects, Charlotte Clark came to the class and gave a lecture about sustainability. Charlotte and I asked the students to post information about sustainability tradeoffs between project materials they were considering, using Sakai’s wiki tool.  This was an ungraded assignment, and not surprisingly some students spent more time on it than others, so there were varying levels of commitment, input, and learning. I thought the assignment worked fairly well to get sustainability involved in the thought process of the class without making it too time consuming. (Many of these students already spend 200 hours or more working on their projects) We didn’t discuss this activity again in class, but some of my students afterward said that they liked the lecture and thought that the concept of life cycle design was interesting and important for engineers to consider.

In the lab, I asked the students to be mindful about what materials they used and what they threw out. Rather than automatically jumping in the car to go to Home Depot to get a chunk of wood, could they use something already in the lab? Maybe there’s some wood with holes that might not look as attractive but would work fine for an early prototype.  A couple of the teams mentioned to me choices that they made because they were trying to be more sustainable, especially spending more time looking for materials in the lab.

I originally considered having a trash-free lab, like the Eno River Festival’s trash-free focus, but I saw quickly that it was impractical. Instead, I asked them to be mindful about not throwing out recyclables. I’ve been surprised at how some of my engineering students don’t automatically recycle. I’d thought to have a board of shame and a board of praise: If I found something in the trash that could be in the recycling and I knew who put it there, they’d go up on the board of shame, and if they did something good they’d move over to the board of praise. I wanted it to be friendly, and it didn’t turn into a big thing, but I did have one person go up on the board of shame who quickly recovered to the board of praise. Overall, we had far fewer recyclables, especially paper, in the trash this year. During cleanup at the end of the semester, several students asked me whether different materials could be recycled, which hadn’t happened with previous classes. With some of the materials I was surprised that they didn’t know already what was recyclable and what wasn’t, but I was happy that they were thinking about it.

We went off campus a couple of times; in particular, at the end of the semester we went to Raleigh to give poster presentations at a conference. One of the students volunteered to create a Google doc for carpooling, and we saved some trips that way. I think it also got them thinking more about this aspect of sustainability.

I have a few thoughts for next year. I might make the wiki research assignment more structured, so that the end products are more equal in investment. My students keep a lab notebook, including documentation of their project work as well as other assignments, and I may have them reflect on their own research that went into the wiki as well as that of some of their peers’ entries. At the end of the semester, I may ask them to write about whether they made any different choices based on their awareness of sustainability. Related to recycling and material reuse in the lab, I may create a competition between groups, something to make it more fun and interesting.

My students also give presentations on engineering ethics, typically related to product development or medical research. (For example, what happens if a product is designed poorly and people get hurt? How will we respond to the myriad issues related to new genetic knowledge?) In the future, I may also allow them to discuss ethical issues related to sustainability, such as resource use and pollution in product design and manufacturing.

I’m glad that that there was a way to formally incorporate some ideas about materials and sustainability into BME 460, and that the Trillium program provided support to make it happen. The activities seemed to help the students understand how their choices as engineers can make a difference.  It was often straightforward to relate some choices about sustainability to their class projects; more importantly, I hope that they will take this awareness to their lives after graduation, regardless of their careers.