University of Sydney students have designed and built a groundbreaking plug-in electric car that does away with axles, gearboxes and mechanical brakes.
The ManGo has a 48-volt lithium-ion battery to power the motors and boasts a regenerative braking system that allows it to top up its battery as it drives.
The car is the brainchild of 50 students from the university’s engineering department. They spent five months developing the specifications and hand-building the car.
“It’s a pretty radical design: a 4-wheel-drive (vehicle) with a motor in each wheel, eliminating the need for mechanical brakes,” Associate Professor Michael Roberts says in a statement.
“The motors are used as brakes and actually recharge the car’s battery when it is running down hill. There are no axles, differentials or gearboxes.”
By placing motors in each wheel, the weight and complexity of gearboxes, differentials, axles and shafts are eliminated and replaced with electronics controlled by a small computer and software.
Mass is reduced further in the ManGo, because the lightweight car operates with smaller motors and fewer batteries than other electric vehicles.
“The car is nimble, light and inexpensive to run,” as well as simple to build, Roberts says.
The ManGo 2-seater is so light two people can pick it up.
The heart of the ManGo is its powerful and efficient wheel motor. There is one pancake-shaped motor about the size of a disc brake and weighing only a few pounds, inside each wheel hub.
Using rare-earth magnets and a new laser-cut winding system, four of these motors can deliver three times the acceleration of the average small car, the design team says. Combining the motor and wheel eliminates the need for most mechanical components.
Roberts says the ManGo’s wheel motors offer triple the efficiency of a gasoline engine. That is further boosted, because electrical energy can be recovered and used to recharge the battery.
The prototype would require much more engineering to become a marketable vehicle, he says. A sketch shows a door-less car most closely resembling a canopied golf cart.
But Ross points to the opportunity presented by the relative simplicity of EV technology and the low barriers to entry for the emerging industry.
“It reminds me of the emergence of computer hardware in California 30 years ago,” he says. “Back then, big-name companies such as Sperry-Univac, Control Data and Burroughs dominated the computer industry. These companies are now consigned to the history books, having been usurped by the PC.
“I see the same think happening with cars. While the big names in the industry are fighting for survival, there is an opportunity for smaller companies to enter the field with a simpler product that better meets consumer demand.
“An electric car, like the University of Sydney’s ManGo with its four wheel motors, could be the start of a new era for Australia, if we have the vision and courage to seize the opportunity.”
General Motors Co. has shown some concepts, including the Hy-wire fuel-cell car, with individual wheel motors at each axle, and Audi AG rolled out its E-tron at this month’s Frankfurt auto show, a concept that employs four electric motors, two at each axle.
