Abstract
My thesis revolves around the persistence of lawnmower injuries in domestic environments, while my technical project focuses on designing and creating a preventative lawnmower safety system that eliminates the possibility of human contact with lawnmower blades through the deployment of a protective guard between the user and blades. My sociotechnical research examines why lawnmower injuries continue to persist despite the dangers posed by lawnmower blades being widely understood. This research argues that consumer safety is more often shaped by warning-based regulation and behavioral intervention rather than engineered injury prevention. While my technical work aims to create a solution to this widespread problem, my STS research questions why safer designs are not already the standard within the consumer safety industry. Together, these two areas of research demonstrate how engineering is deeply intertwined with social influences and impacts. This relationship is reflected in how institutions, regulatory classifications, and cost-driven decisions shape what is considered acceptable in final engineering designs. From this, it becomes evident that STS is deeply embedded within engineering practice, as it helps engineers understand not only how societal systems and influences function, but also why unsafe and inequitable systems continue to persist.
The technical portion of my research resulted in the creation of a preventative lawnmower safety system that eliminates direct human contact with the blades. The system operates through the use of a mmWave sensor that detects when a human enters its immediate proximity and subsequently triggers a mechanical guard to deploy and block access to the blades. This process required the development of an embedded controls system capable of accurate signal processing and rapid real-time response due to the project’s tight operational margins. Additionally, the design accounted for practical engineering considerations such as wiring organization, component identification, and redundant system integration to ensure reliable operation across varying environments. The most significant aspect of the system is its preventative approach to safety. Rather than relying on user reaction after danger is present, the design intervenes before harm can occur. This shifts responsibility for safety away from the user and toward an embedded engineering solution that has not previously been implemented in this context. By creating an automated guarding mechanism, this project provides a proof of concept for how lawnmowers can be intentionally redesigned to better prioritize user safety.
For the STS portion of my research, I examined lawnmower safety as an institutional problem and identified key factors that allow lawnmower injuries to persist within domestic environments. Rather than framing blade injuries solely as a result of user error, my research focused on how regulatory consumer frameworks and product classifications influence what levels of risk are considered acceptable within consumer technologies. Current regulatory frameworks largely emphasize user behavior through safety warnings, labels, and behavioral compliance instead of requiring engineered safety solutions. This stands in stark contrast to industrial safety regulations, where machinery is often required to incorporate built-in mechanical guards that actively prevent human injury. By comparing consumer and industrial safety standards, my research reveals a significant gap that helps explain why lawnmower blade injuries continue to persist. As a result, my research concludes that improving consumer safety, specifically lawnmower safety, requires a shift away from behavioral compliance and toward engineered safety design standards.
Through examining the technical, organizational, and cultural dimensions of engineering, my research demonstrates the broader ethical and societal considerations embedded within engineering decision-making. The technical portion highlights the importance and feasibility of engineered safety solutions, while the STS research reveals why these solutions are not always implemented in practice. The gap between the two demonstrates that engineering decisions are shaped not only by technical feasibility, but also by regulatory pressures, cost constraints, institutional priorities, and broader societal influences. The STS perspectives presented throughout this research are important because they allow engineers to understand not only how to create technical solutions, but also how to navigate the systems and constraints that may hinder their implementation. For me, the combination of technical and sociotechnical research has fostered a mindset that challenges existing frameworks rather than simply accepting them, particularly in the context of preventative safety engineering.
Notes
School of Engineering and Applied Science
Bachelor of Science in Mechanical Engineering
Technical Advisor: Michael Momot
STS Advisor: William Davis
Technical Team Members: Richard Townsley, Jackson Berry, Vincent Hu, Averell Stith, David Cuyuch, Mia Bonutti, Cole Smith
