While General Motors recently came out with its Chevrolet Volt, four electrical engineering students at Missouri University of Science and Technology just completed their own vehicle, a hybrid go-kart.
Built with a mixture of old and new parts, the students’ goal is to demonstrate the efficiency and versatility of vehicles that use more than one power source to help offset the rising cost of fuel and lower dependency on foreign oil.
Traditional combustion engines make best use of fuel at high speeds, so gasoline is wasted in stop-and-go traffic. The students’ hybrid system allows a small combustion engine to run at optimum efficiency at all times to power a generator, which in turn powers a battery system that runs an electric motor that is mechanically coupled to the drive wheel.
The students estimate their hybrid powertrain operates at 70 percent electrical efficiency, getting about 109 mpg, versus an average of 40 mpg in typical go-karts. Their vehicle also reaches 30 mph in eight seconds.
The four seniors, Alycia Yungbluth from Jefferson City, Mo.; Cory Gilliam from Ashland, Mo.; Andrew Jabrani from O’Fallon, Mo.; and Bill Cushman from St. Louis, each worked on a different area of the vehicle.
“We all took a course on hybrid vehicles, but there was a lot to learn to build one on our own,” says Yungbluth. “Our different interests made dividing up the workload easy.”
Yungbluth handled the battery specifications, Gilliam developed an appropriate-sized generator and motor controller, Jabrani sized the engine and motors, and Cushman worked on the monitoring systems for the battery charge.
The project had its share of hurdles, including difficulty finding parts within their budget. The group found and repaired some used parts and purchased some new ones, with the help of grants and donations from local businesses Hutcheson Ford Sales Inc., Investment Realty, Phelps County Bank and John’s Firestone.
One of Yungbluth’s tasks was the initial development of the braking system. Future students will have an opportunity to continue the project by implementing regenerative breaking to the go-kart, a process where braking energy is recovered through the conversion of kinetic energy and applied to the brakes and to the batteries.
This type of hands-on experience is typical for Missouri S&T students and translates well to the job market. All four have jobs lined up after graduation.
The group’s advisor is Dr. Medhi Ferdowsi, associate professor of electrical and computer engineering at S&T. Their course instructor is Dr. Kristen Donnell, assistant teaching professor of electrical and computer engineering at S&T.