Karlsruhe Institute for Technology (KIT) and Schaeffler are developing a new energy-efficient assisted steering system for EVs under the project “Intelligent Assisted Steering System with Optimum Energy Efficiency for Electric Vehicles (e²-Lenk)” subsidized by the German Federal Ministry for Education and Research (BMBF).
In conventional vehicles, the internal combustion engine supplies on-board systems such as assisted steering, with the requisite energy. In electric vehicles, this energy comes from the battery and also reduces the range as a result. In the KIT and Schaeffler project, the steering system is assisted in an energy-efficient manner by intelligent control of the drive torques transmitted to the individual wheels. The project is being sponsored by BMBF with a sum of around €0.6 million (US$0.65 million) over 3 years and was started in January 2015.
The new assisted steering system would require less system components in an electric vehicle, this would mean savings in terms of weight and energy in an electric vehicle. This would mean that an electric car would be cheaper and have a greater range.—project managers Dr. Marcel Mayer, Schaeffler, and Dr. Michael Frey, KIT
Further, materials and production steps can be saved due to the potential optimization of the design and weight.
The basic concept of the e²-Lenk project is simple: the wheels in an electric car will be 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, said Mayer, Manager of the Automatic Driving Working Group at Schaeffler, which is carrying out research as part of the collaborative research project SHARE (Schaeffler Hub for Automotive Research in E-Mobility) at KIT.
As part of the project, functional demonstrators are being built, with which the concepts can be validated and optimized in experiments. The partners also plan to implement the system in last year’s Formula Student racing car KIT built by the university group KA-RaceIng with the participation of the students.
e²-Lenk is the first publicly subsidized joint project as part of the collaborative re-search project SHARE at KIT between Schaeffler Technologies AG & Co. KG and KIT. This joint project is being managed at KIT’s East Campus in a joint project management office run by SHARE at KIT and the Institute of Vehicle Systems Technology (FAST).