A team of engineers at Ohio State University want to change the way cars work. Not only do they want to build a more efficient, environmentally-friendly vehicle, but they also want to build a car with better parts—in fact, so much better that you can do away with major components... like a conventional engine.
The prototype developed by Junmin Wang and collaborators is futuristic, indeed. The electric car has no engine, no transmission, and no differential, because each wheel has its own battery-powered motor. The car's computer brain employs a number of complex algorithms to sync up the wheels and to ensure the car drives smoothly and handles well. Using input from the accelerator, brake, and steering wheel, it also analyses data as often as 100 times per second. The vehicle's also about half the weigh of a normal car, boosting its efficiency.
In a sense, the car's smart enough to tell each wheel to exert exactly as much force as it needs—no more—for a smooth ride. "One wheel can be doing the braking, while another is doing the driving," Wang explains. "The computer gets signals from the driver from the steering wheel and pedal positions, then calculates the desired speed, or vehicle motion, based on a mathematical model." A car that runs on math? Not a bad idea. Eventually, he says, it will "handle better than typical conventional cars."
Of course, this isn't the first car to use independent motors in each wheel. Five years ago, Michelin developed its so-called "Active Wheel" that managed to do away with the engine and exhaust system. Wang's system promises to be even more efficient, however, and is currently being tested on a utility terrain chassis that can run eight to ten hours on a single charge.[OSU]