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Polygence Scholar2023
Junghyun Koh's profile

Junghyun Koh

Class of 2024Troy, New York


Hello! My name is Junghyun and my Polygence project is on building an accessible, compact, and convinient gym equipment using electromagnetic induction. I chose to work on this project because I wanted gym experience to be more welcoming to beginners and those who are interested but have limited access to various types of gym equipment. After my project is complete, I would like to build up on my project to further nourish my interest in mechanical engineering involving sports science.


  • "The Influence of the Shape of the Cam Pulley on Leg Extension Machines" with mentor Aaron (Sept. 15, 2023)

Project Portfolio

The Influence of the Shape of the Cam Pulley on Leg Extension Machines

Started Mar. 21, 2023

Abstract or project description

The optimal design of leg extension exercise machines is crucial in effectively targeting and activating the quadricep muscles during exercise. This research paper investigates the shape effectiveness of the cam pulley on leg extension machines on the tension in the user’s quadriceps. This study surveyed three subjects for anatomical measurements, collected data using two different selectorized leg extension machines, and calculated the force and torque. The results provide insights into the function of the non-circular shape of the cam pulley in designing leg extension machines. This keeps the force on the shin pad consistent by applying more force during certain periods throughout the course of leg extension. With this insight, a design of a leg extension machine accounting for the differences in each individual’s leg weight is proposed.