All Electric Concept – Audi Urban Debuts at Frankfurt

In Audi by Jonathan Humphrey

Radical pair of all-electric technology studies offer a glimpse into the potential future of urban mobility   

  • Audi urban concept study – in both Sportback and Spyder forms – unveiled at the Frankfurt Motor Show
  • Sleek 1+1 seat cockpit made from CFRP, free-standing wheels with protective plates
  • Elaborate suspension design, compact electric drive system for sporty performance
  • The Spyder version has one low, continuous window and doors that open diagonally upwards

Ingolstadt, September 13, 2011 – Audi is breaking new ground with its urban concept technology study, a 1+1 vehicle for city driving. The electric-powered show car has four wheels, but does not fit into any current automobile category. Weighing just 480 kilograms, the Audi urban concept combines elements of a racecar, a roadster, a fun car and a city car into a radical new concept. It has the potential to set the trend for a new form of mobility. 

The question “How much car is necessary to deliver driving pleasure and urban mobility in an entirely new way?” was the starting point for the Audi urban concept. A model of a glider was kept in the studio during the development process as an example of lightweight construction, efficiency and reduction – of the principle of ‘less is more.’

The result is a vehicle that defies pigeonholing; a vehicle that redefines the term ‘driving pleasure’ and is completely free from the baggage of conventional concepts. The design of the Audi urban concept concentrates on the pure essence and freedom of driving in a premium form. At the same time, it offers the comfort and safety of a closed automobile, an important advantage over a motorised scooter. With its sleek body and free-standing wheels, the technology study is progressive and dramatic while being extremely agile and comfortable.

The cabin of the Audi urban concept offers slightly offset seating for two. The roof slides back to allow the driver and passenger in. This innovative solution makes the Audi urban concept even more fun to drive because the canopy can be left open in good weather. It also allows the cabin to be aired out very quickly. The fit and finish of the show car is characterised by the usual Audi attention to detail, while its technology is indicative of the brand’s wide-ranging expertise, particularly in ultra-lightweight construction.

The brand with the four rings has created an entirely new class of premium vehicle with the Audi urban concept, which now marks a new entry point to its future array of electric vehicles, which includes the range-topping R8 e-tron high-performance sports car.

The technology study is targeted at people who are interested in technology and are enthusiastic about new approaches to mobility, irrespective of their age and status. In particular, it appeals to urban drivers whose lifestyles embrace the car’s modern concept and the driving pleasure associated with it. The urban concept is also a good fit for a possible innovative leasing system.

Exterior design
The Audi urban concept features an all-new design that evokes design parallels with the Auto Union racecars of the 1930s. They were well ahead of their time conceptually: they were extremely lightweight and their engines were mounted in the rear. Their large, open wheels also stood out from the chassis – another parallel with the modern show car.

Painted in Electric White, pearl effect paint, today’s technology study – 3,219 millimetres (126.73 in) long, 1,678 millimetres (66.06 in) wide, but just 1,189 millimetres (46.81 in) high – has a body on which all the lines surge forward. The greenhouse is extremely flat, and the roofline drops down like a wedge while the side window rises upward. The typical Audi tornado line gives the urban concept a strong shoulder.

An upright, forward-leaning blade in front of the rear wheel accentuates the side view. The Speed Red contour line gives the appearance of a roll bar and evokes the Audi R8 high-performance sports car. The flanks of the body flare outward toward the bottom to enlarge the floor. This serves two purposes: It generates downforce at higher speeds and it can be used to charge the battery via induction – a particularly convenient way of recharging the battery.

The characteristic Audi single-frame grille, which sports the four rings, appears as a closed surface on the Audi urban concept. It tilts forward to provide access to the charging socket. The narrow LED headlights project three-dimensionally from the body.

The indicator signals are LED strips running along the wings. These closely encircle the free-standing wheels, and the front wings turn with the wheels when steering. The three-dimensional rear lights with the tail light and brake light are integrated into the vehicle body and wrap around the top of the rear window. At the back of the car is a small luggage compartment that pulls out like a drawer.

The front segment of the greenhouse is movable – another innovative idea that is unique to the Audi urban concept. Mounted on rails, it can be slid back by hand over the fixed rear segment.

The driver can decide whether to close the canopy or leave it open. The technology study is a roadster-on-demand that has neither roll-down windows nor a heavy air conditioning system. When closed, the canopy provides protection against inclement weather. Audi has also developed a second body variant as an alternative to the urban concept: a Spyder with a flat window strip wrapping around the cockpit and doors that open upward at an angle.

Entry to the Audi urban concept is possible when the canopy has been slid backwards. The driver and passenger step over the edge of the vehicle as if they were stepping into the bathtub – there are no doors. This does not require any great flexibility; a handle on the windshield frame and special cutouts on the seats make entry simple.

The show car offers room for two. The driver and passenger sit next to one another, with the right seat offset to the rear by 30 centimetres (11.81 in) to provide more shoulder and elbow room. The seats are fixed, integral components of the monocoque, which results in significant weight savings. The seats are upholstered with materials that have been made to the measurements of the driver, just like in a racecar. The seat belts run through cut-outs in the seat backs.

Sitting in the Audi urban concept is like sitting in the cockpit of an aeroplane. The seating position is very sporty. The driver can precisely adjust the positions of the aluminium pedals and the steering column. The pedals can be moved a total of 22 centimetres (8.66 in), while the steering column can be moved 14 centimetres (5.51 in) for easier entry and an additional six centimetres (2.36 in) for a custom driving position.

The steering column is exposed – a thick, elegantly designed section, open in the centre and mounted almost horizontally. At the far end of the steering column is a display of the most important driving information. The small, hexagonal steering wheel includes buttons and roller switches for controlling various systems, including the Audi drive select modes for the electric drive system.

The entire interior of the technology study is designed to meet the strict dictates of ultra-lightweight construction. Running below the windscreen across the entire cabin is a wing-shaped section that is open in the middle. This new style of dashboard includes satellite controls for the heater and two large air vents.

Rather than carpeting, an innovative mat covers parts of the floor. This is made from a material originally developed for athletic shoes that is water repellent and very durable. The seats are covered with cloth, with the edges framed in kangaroo leather. Aluminium applications accentuate elements on the dashboard.

The outer skin of the show car is made of carbon fibre-reinforced polymer (CFRP); the occupant cell is a mix of CFRP monocoque and an aluminium structure. This ultra-lightweight construction is the foundation for the technology study’s extremely low kerb weight of just 480 kilograms.

The sophisticated chassis underscores the distinctively sporty personality of the Audi urban concept. Wishbones made from a combination of aluminium and CFRP locate the free-standing, 21-inch wheels.

Manufactured using cladding technology, the wheels are very light and feature a variant of the blade design from the Audi e-tron models. The tyre sizes are as unusual as the car – 125/60 at the front and 145/50 at the rear.

The Audi urban concept uses pushrod technology borrowed from motorsport. As in a racecar, the struts mounted in the interior of the monocoque are nearly horizontal. Four disc brakes provide the stopping power. The turning circle measures less than nine metres – ideal for a city car. Thanks to the vehicle’s low weight, the rack-and-pinion steering does not require any power assistance. Crumple zones in the front and rear plus two airbags offer for a high degree of passive safety. An innovative assistance system helps the driver to avoid collisions with pedestrians.

The battery is mounted transversely behind the seats. The lithium-ion battery, which weighs around 90 kilograms, stores 7.1 kWh of usable energy. The study’s two electric motors together produce 15 kW (20 PS) of continuous power and 47 Nm (34.67 lb-ft) of torque. The motors are mounted between the rear wheels, which they drive via a single-speed transmission.

The Audi urban concept accelerates from 0 to 62mph in 16.9 seconds. It reaches 37mph in around six seconds. The show car steps off from traffic lights smartly thanks to the torque of the electric motors, which is fully available from standstill. Top speed is governed at 62mph.

The action radius in the European driving cycle is just over 45 miles. The battery recharges completely in about 20 minutes with 400-volt, three-phase current, and in approximately one hour with 230-volt household current.

Audi Wireless Charging
Audi is developing an alternative to charging at a power outlet – Audi Wireless Charging (AWC) is contactless induction charging. The infrastructure side, comprising a coil and an inverter (AC/AC converter), could be built into the normal parking space of the Audi urban concept and connected to the power grid. The 3.6 kW primary coil set into the plate generates a high-frequency alternating field.

The charging process begins automatically when the urban concept is driven onto the plate. The alternating magnetic field of the infrastructure side induces an alternating current across the air gap in the secondary coil, which is integrated into the vehicle. This current is rectified and fed into the vehicle’s electrical system, where it charges the battery or powers systems such as the heater. The alternating field is only generated if the vehicle is parked over the plate and so poses no danger to people or animals.

Charging stops automatically when the battery is fully-charged, and can be interrupted by the driver at any time. The efficiency of AWC is comparable to that of other charging technologies. It is not affected by rain, snow or ice. The new technology makes charging electric vehicles easy and extremely convenient. A future version of the technology will be suitable for integration into the transportation infrastructure as a retrofit for car parks or residential streets, for example.