"This is a very large business card that showcases all of our capabilities," quipped Kevin Fisher, Tata Technologies' President of Vehicle Programs & Development (VDP), pointing to the engineering service company's first-ever electric concept car.
Tata Technologies' eMO (electric MObility) engineering study concept car uses an air-cooled 18.4 kW·h lithium-ion battery to drive two ac induction motors that are coupled to the front wheels. According to Kevin Power, Tata Technologies' Lead Electrical Engineer, the patent-pending "innovation is that the motors function independently of one another."
The liquid-cooled, dual-motor, front-wheel-drive system is unique when compared to current production EVs, which use a single electric motor and a differential.
"When attached to a wheel hub, the motor's weight affects the car's ride and handling. Rather than using hub motors, each motor on the eMO is located on the suspension side. So instead of being part of the unsprung mass, the motors are part of the sprung mass," explained Power.
Instead of a mechanical differential, the concept car uses electronics and control algorithms to handle the functions typically performed by an actual differential.
"We haven't fully developed the software code and algorithms yet, but we have done enough work to convince ourselves that it is feasible to take this approach. We believe the powertrain configuration that we're proposing will greatly enhance the driveability and safety of the car," said Power.
While the eMO concept is a front-wheel-drive A-Class car, development of an all-wheel-drive version is under consideration.
"It would become a more complex system from a software, architectural, and component standpoint, but we believe it is possible," Power said.
In its present configuration, eMO uses independent front lower A-arm and MacPherson struts. The rear suspension has a semi-trailing link with separate mounting points for shock absorbers and springs. eMO also features an antilock braking system with electronic stability control and an electric-power-assisted rack-and-pinion steering system.
The concept car's steel structural frame is complimented by molded-in color recycled polymer door panels as well as front and rear fascias.
eMO emphasizes unconventional exterior design cues, according to Warren Harris, President and Global COO of Tata Technologies.
"We've incorporated the LED taillights into the rear glass for a seamless look. The car's panoramic windshield and glass roof is unusual. We do not know of any other electric vehicle that has taken the windshield as far up and rearward on a car as we have with the eMO," said Harris.
During the more than 18 months of eMO related development work, the engineering services firm applied for 15 patents to address product features, materials methodology, and architectural elements. The car also has been designed to meet all FMVSS requirements.
Although eMO is not slated for production, it was designed to target a suggested selling price of $20,000.
The firm's VDP teams in Pune, India; Coventry, England; and Novi, MI worked on the eMO engineering study.
The eMO has a wheelbase of 85.8 in (2180 mm), matching front and rear tracks of 53.9 in (1370 mm), an overall length of 117.9 in (2995 mm), a width of 60.6 in (1540 mm), and a height of 62.2 in (1580 mm).