Hi, I’m Sarah Nguyen. This summer, I worked on designing and testing modular robotic fins to improve aquatic locomotion in the STARQ robot. Inspired by biological swimmers like beavers and otters, our goal was to enhance swimming performance through innovative fin attachments tailored for two swimming gaits: the doggy-paddle and dolphin-kick. We developed two types of fins—hinge fins (3D-printed with built-in flexibility to adjust drag across stroke phases) and duck fins (molded from soft elastomer for flexibility). We tested both designs at various frequencies in controlled trials, analyzing velocity data through video tracking. Results showed performance differences based on fin type and gait, with future plans including material optimization and adaptation to other robotic platforms.