It’s no secret that the automotive industry as a whole is pushing for better fuel economy and reduced emissions. With polar ice caps melting and Johnny Polar Bear losing his home, automakers are forced to figure out new and innovative solutions to help reduce our overall carbon footprint. While electric cars and hybrids are the future, our current infrastructure needs time to catch up to the technology. So in the meantime, automakers must create other innovations that can help save fuel and improve efficiency in other areas. Which is exactly what Audi is doing with its new electromechanical dampers.
Electromechanical Rotary Dampers, or eROT as Audi calls them, are a new form of shock dampers that not only improve ride comfort but also provide and added boost of efficiency. It’s actually quite brilliant and is probably the most innovative suspension setup since the hydropneumatic suspension in the Citroen DS. The idea behind these eROT dampers is to absorb the kinetic energy of shock absorbers and put it back into the vehicle.
“Every pothole, every bump, every curve induces kinetic energy in the car. Today’s dampers absorb this energy, which is lost in the form of heat,” said Dr.-Ing. Stefan Knirsch, Board Member for Technical Development at AUDI AG. “With the new electromechanical damper system in the 48-volt electrical system, we put this energy to use. It also presents us and our customers with entirely new possibilities for adjusting the suspension.”
Replacing the traditional upright shock absorbers of a standard car, the eROT dampers are horizontally-arranged electric motors in the rear axle area. These motors have a steel lever arm that attaches to the wheel carrier and this lever arm is what absorbs the motion of the wheel moving vertically. It then transfers that kinetic energy through a series of gears to an alternator which transforms that energy into electricity. It’s fascinating and quite brilliant (the top image gives a perfect breakdown of how it works).
This new eROT suspension setup can return about 100 – 150 watts of electricity on an average German road. A freshly paved highway will only return about 3 watts while an incredibly bumpy road can return about 600 watts. The bumpier or twistier the road, the more energy the suspension recuperates. But because the damping of the electric motor and geartrain in the eROT suspension is infinitely variable, via software, it’s actually far more comfortable than a standard shock absorber.
The only caveat to this system is that it requires Audi’s new 48-volt electric system to be on board, as that’s what powers the suspension and where the energy goes back into Currently, the Audi SQ7 is the only Audi-branded product to have such a system (its VW Group sibling, the Bentley Bentayga also has it). However, in the future, Audi wants the 48-volt electric system to be the main system in all new models. With this eROT system, new Audi hybrid vehicles could see an increase in fuel economy by up to .7 liters per 100 km, which is quite remarkable.
With this new eROT electromechanical suspension setup, Audi has not only found an additional way to help our world’s problem while also making cars ride more comfortably. It’s almost impossible to argue with those results.