Making the most from every bump
Cars as we currently know them, regardless of how far the automotive industry has advanced in recent years, are still horribly inefficient beasts. According to the US Department of Energy, a midsize modern conventional petrol powered car loses around 65% of its fuel energy through its engine alone.
Each and every car manufacturer has many a mad scientist hard at work, trying to find ways to recuperate some of this lost energy. In 2009, Formula One introduced us to the KERS system, a form of regenerative braking. KERS works by transferring a car’s kinetic energy from its brakes, and then storing it in a reservoir to later aid the car’s engine when under acceleration. Electric vehicles can also be equipped with a form of regenerative braking. For example, Tesla’s system actually allows the motor to spin in reverse, depending on the position of the throttle, which also allows energy to be stored as electricity, and can be used to drive either set of wheels for a bit of extra boost.
So energy recuperation via regenerative braking is nothing new, but wouldn’t it be cool if other moving parts could also be used to generate some additional energy? That’s exactly what Audi’s mad scientists have been busy cooking up. The Electromechanical Rotary Damper, or eROT for short, is a brand new prototype which replaces the conventional hydraulic damper system with electromechanical units, which connect to a 48-volt axle-mounted lithium-ion battery. While conventional dampers lose energy through heat dissipation, an eROT system can instead collect this energy, which can then be used to power other electric vehicle functions, such as the lights or accessories. Audi claim that eROT can recuperate an average of 100-150 watts on a range of German roads, and of course the rougher the road, the more energy the system can collect, with up to 613 watts being collected on rough secondary roads during testing.
Redefining damping
If this isn’t already enough to get you excited, then perhaps this next bit will. Not only is eROT capable of recuperating lost energy, but is also an actively controlled suspension, meaning that it adapts to irregularities in the road surface, as well as to the driver’s driving style. Audi claim that it also eliminates the mutual dependence of the rebound and compression strokes that limits conventional dampers. This essentially means that in theory the damper can be both comfortably soft, yet retain the firm damping characteristics necessary for faster cornering. The eROT perhaps then spells the beginning of the end to the spine-shattering compromise often made when in pursuit of a more sports oriented machine; we do hope so!
The eROT is a funny looking thing, which as you may have already gathered replaces traditional damper and spring units with horizontally mounted electric motors. As an additional little bonus, this also allows for extra room in the luggage compartment. Nice!
Now, of course we have to snap back to reality and remember that this awesome new technology is still only in its prototype stage, although Audi has said “Initial test results for the eROT technology are promising, thus its use in future Audi production models is certainly plausible.” Now this does sound quite promising to us. Regardless of whether this particular version makes it to the production line, the technology is clearly in the pipeline, and when it fully emerges just imagine the possibilities for the EV world. No doubt we will eventually see even more efficient derivatives, which could contribute energy towards an increase in range, power or both and more!
