New steering system proposed to increase electric-car efficiency

Electric cars may not burn any fossil fuels to propel themselves, but that doesn’t mean there shouldn’t be any attempts to improve their efficiency.

Decreasing the amount of energy a car needs to travel a given distance increases range, and lessens the car’s overall carbon footprint. Those are two important goals for buyers with range anxiety, or those who want their vehicles to have the lowest environmental impact possible.

To that end, the Karlsruhe Institute of Technology (KIT) in Germany and automotive supplier Schaeffler are working to develop a new type of steering system specifically for electric cars that could improve their efficiency.

As with most internal-combustion cars, electric cars use a power assist to decrease steering effort. This draws electricity from a car’s battery pack, affecting range, the two partners note.


Electric cars can be provided with steering assistance by means of an intelligent control system and suitable wheel suspension

KIT and Schaeffler propose a system that does away with the standard apparatus of a steering column linked to the wheels by tie rods. Instead, the prototype system uses individual electric motors for each of the front wheels to steer.

To keep a car traveling in a straight line, each motor imparts an equal amount of force on its wheel.To turn, the system sends more power to the outside wheel; so if the driver wants to go right, the left wheel is given more power in order to turn faster and change direction.

The developers describe the system as being similar in principle to tracked vehicles, which brake one set of tracks in order to turn rather than physically changing their direction.

It also sounds similar to the torque-vectoring systems used on some production cars to improve handling. These systems send more power to one wheel or one side of the vehicle, spinning the wheel or wheels faster and helping rotate the car into a corner.

KIT and Schaeffler have received 600,000 euros ($660,000) in funding from the German Federal Ministry for Education and Research (BMBF) over three years for the project, which commenced in January.