Energy-efficient steering designs for electric vehicles
30 March 2015
A German research team is investigating a new techique for steering electric vehicles that doesn't drain battery power otherwise required by steering assist systems.
In electric vehicles, the energy required by steering assist systems comes from the battery and thus reduces their range as a result. In this research project being conducted by Karlsruhe Institute for Technology (KIT) and Schaeffler, the steering system is assisted in an energy-efficient manner by intelligent control of the drive torques transmitted to the individual wheels.
"The new assisted steering system would require less system components in an electric vehicle, meaning savings in terms of weight and energy," say project managers Dr Marcel Mayer (Schaeffler) and Dr Michael Frey (KIT). "This would mean that an electric car would be cheaper and have a greater range."
The basic idea of the e²-Lenk project is simple: the wheels in an electric car are driven individually by electric motors in contrast to a car with an internal combustion engine where all the wheels are provided with equal force.
If the wheels on the left side transmit more drive torque to the road than those on the right side, this will result in acceleration of the vehicle to the right without the need to turn the front wheels or consume additional energy for steering. Tracked vehicles or quadrocopters steer using the same principle.
"Steering assistance can be provided while driving by means of an intelligent control system and suitable wheel suspension", says Dr Mayer. "Only steering when stationary remains a challenge with conventional designs."