Cornell Electric Vehicles is an undergraduate engineering project team dedicated to building the world's most efficient electric vehicle.
Our team competes in the Shell Eco-Marathon (Americas) and has placed 5th in 2018 and 3rd in 2019
2019-2020
This past year, I lead the Rear Assembly subsystem and was responsible for developing the drivetrain system for the 2020 vehicle. I focused on minimizing the energy losses within the system by optimizing motor efficiency, transmission efficiency, and overall weight.
Although the 2019-2020 competition season was cut short due to Covid-19, I still managed to complete around 90% of the drivetrain subsystem.
I designed and manufactured an adjustable motor mount with built-in chain tensioning capabilities. The motor mount has 2 degrees of adjustability to ensure proper chain alighnment and allows fine adjustments in chain tension using a tensioning bolt. A static structural analysis was performed on the entire assembly for weight optimization. All components were manufactured on a router mill and manual mill.
I concluded from prior research that larger sprockets increase the efficiency of a sprocket and chain transmission. As a result, I designed and manufactured a 22 inch diameter sprocket for the transmission. A static structural buckling analysis was performed on the sprocket to validate its performance and optimize its weight. The sprocket was then waterjet cut from a 2ft x 2ft x 1/8in aluminum sheet, and a 3D printed sanding jig was used to create a slight chamfer along the teeth.
I researched brushless DC electric motors in order to select the most efficient motor for our vehicle. I learned how to generate motor efficiency graphs and understand test data charts in order to compare the efficiencies of various motors. I eventually selected a motor that should drive our vehicle at around 90% efficiency.