Amping up the voltage

by | Jan 7, 2021 | Inside Mines, Winter 2021 | 0 comments

When 2020 graduate Gracie Cole’s parents bought a brand-new Volkswagen bus for their growing family in 1979, they had no idea one day it would be converted from a combustion vehicle to an electric one. But that’s exactly what happened when Cole bought the vehicle from her parents a few years ago and turned it into her senior design project, called Re-Volt. The bus was in great shape, and Cole saw a way to bring a classic into the future.

“I’m not fixing this because it’s broken,” Cole said. “This project is a way to improve the performance and reliability but also to keep it relevant in the decades to come.”

The team

Cole said the learning curve isn’t so much on the combustion side—it’s the electrical components that pose the biggest challenge—so setting up a senior design team with students from different disciplines was key. Three electrical engineering and 12 mechanical engineering students currently work on the project.

“We rely heavily on our electrical engineers, but mechanical is a necessary integration, too,” Cole said. “We’ve been able to work really well together.”

The conversion

One of the biggest factors in the conversion was making sure the bus can not only keep up with traffic, but travel long distances with minimal charging, like the cross-country trips Cole’s family took when it was fresh off the assembly line.

The Re-Volt team was able to keep the Volkswagen’s existing transaxle and transmission, which will integrate seamlessly with the new design and connect to the electric motor. Eighteen Tesla Model S batteries are going to be arranged in three parallel packs of six. A motor controller, which connects to the electric motor, relays performance commands based on user input. The embedded systems subsystem will make all the various components talk to each other and monitor everything, including relaying the cabin temperature and telling the user interface how hot the batteries are.

What’s next

Cole’s first road trip to test out the new system when the project is complete? “Maybe take a drive down the California coast,” she said. “I don’t know if it gets more iconic than that.”

Follow along with the Re-Volt team’s progress at