The Audi TT offroad concept breaks the mold, combining the sportiness of a coupe with the lifestyle and utility of a compact SUV. The four-door model, which Audi is presenting at the Beijing International Automobile Exhibition, adds an entirely new expression to the Audi design language. Its plug-in hybrid drive with two electric motors and a system output of 300 kW (408 hp) provides for dynamic performance, yet consumes on average just 1.9 liters of fuel per 100 kilometers (123.8 US mpg).
“The Audi TT offroad concept provides a glimpse of how we might imagine a new model in the future TT family,” says Prof. Dr. Ulrich Hackenberg, Member of the Board of Management for Technical Development. “It combines the sporty genes of the TT with the strengths of a compact Audi SUV. Its plug‑in hybrid drive with the option of inductive charging is a major step toward the mobility of the future. We chose to present the Audi TT offroad concept in China, our second domestic market, because it represents the urban mobility of tomorrow: It is sustainable, dynamic, intelligent and connected.”
The plug-in hybrid drive
The plug‑in hybrid drive in the Audi TT offroad concept delivers 300 kW (408 hp) of system output and 650 Nm (479.2 lb‑ft) of system torque. The show car accelerates from 0 to 100 km/h (62.1 mph) in 5.2 seconds and reaches the electronically governed top speed of 250 km/h (155.3 mph) without any trouble. It consumes just 1.9 liters of fuel per 100 kilometers (123.8 US mpg), a CO2 equivalent of 45 grams per kilometer (72.4 g/mile).
The Audi TT offroad concept can drive over 50 kilometers (31.1 miles) solely on electric power and thus with zero local emissions, and has a total range of up to 880 kilometers (546.8 miles).
The combustion engine is a 2.0 TFSI producing 215 kW (292 hp) and 380 Nm (280.3 lb‑ft) of torque. The two-liter, four‑cylinder unit with the large turbocharger is packed with Audi's potent efficiency technology. At part load, indirect injection supplements gasoline direct injection for lower fuel consumption. The exhaust manifold is integrated into the cylinder head – the foundation for the high-performance thermal management system.
A separating clutch links the transverse 2.0 TFSI to an electric motor producing 40 kW and 220 Nm (162.3 lb‑ft) of torque. The slim, disc-shaped electric motor is integrated into the six-speed e‑S tronic. The dual-clutch transmissions sends the torque to the front wheels. Mounted on the rear axle of the Audi TT offroad concept is a second electric motor independent of this drive unit. This produces a maximum of 85 kW and 270 Nm (199.1 lb‑ft).
In front of the rear axle is a liquid-cooled, lithium-ion battery comprising eight modules. It contributes to the balanced 54:46 weight distribution between the front and rear axles and to the low center of gravity. The battery stores up to 12 kWh of energy, enough for an electric range of 50 kilometers (31.1 miles). An Audi wall box, which manages the energy feed conveniently and intelligently and can deal with a variety of voltages and outlets, is used for stationary charging.
The show car is also designed for use with Audi Wireless Charging technology for contactless inductive charging. The infrastructure side – a plate with a coil and an inverter (AC/AC converter) – is placed on the parking spot of the Audi TT offroad concept and connected to the power grid. The charging process begins automatically when the car drives onto the plate. The alternating magnetic field of the infrastructure side induces a 3.3 kW alternating current across the air gap in the secondary coil, which is integrated into the vehicle. The current is inverted and fed into the electrical system.
Charging stops automatically when the battery is fully charged. It takes about as long as charging via a cable, and the driver can interrupt the process at any time. The Audi Wireless Charging technology is more than 90 percent efficient, and is not affected by weather factors such as rain, snow or ice. The alternating field, which is only generated when a car is on the plate, is not harmful for people or animals.
The intelligent plug‑in hybrid concept of the Audi TT offroad concept really shines when driving, making the show car every bit as efficient as it is sporty. The Audi drive select management system offers three driving modes. EV mode gives priority to electric driving. In this case, the front drive unit is inactive, and the electric motor at the rear axle with its powerful torque can rapidly accelerate the four‑door car to a maximum of 130 km/h (80.8 mph). In Hybrid mode, all three drives work together in various ways as necessary. In many situations the front electric motor assumes the role of a generator.
Powered by the engine, it recharges the battery and thus extends the electric range. Full system output is available in Sport mode. During “boosting,” i.e. strong acceleration, the rear electric motor works together with the 2.0 TFSI. The same thing happens when the hybrid management system decides that all‑wheel drive is appropriate. In such situations, e.g. on a slippery road or in light off-road conditions, this essentially makes the Audi TT offroad concept an e‑tron quattro.
When the driver takes his or her foot off the accelerator, free-wheeling or “coasting” is activated. Recuperation occurs here at low speeds and when braking. The driver can use the “Hold” and “Charge” functions in the MMI system to specifically influence the battery's charge state, e.g. to increase storage of electric energy so that it can be used over the final kilometers to the destination.
Chassis
The Audi TT offroad concept shows its strong character on any road surface and in any terrain. On asphalt the show car is sporty and composed, and it can easily handle light terrain thanks to its high ground clearance, short overhangs and e‑tron quattro all-wheel drive. 255/40-series tires are mounted on 21‑inch wheels, whose delicate five-arm design draws on the look of the Audi e‑tron models. Dark trim provides contrast.
Many of the components of the McPherson front suspension are made of aluminum; the four‑link rear axle handles longitudinal and transverse forces separately. The ratio of the progressive steering changes with the steering input. The Audi drive select system allows the driver to modify the function of various technical modules in multiple steps.
Driver assistance systems
The Audi TT offroad concept show car features two Audi driver assistance systems that are almost ready for production: the intersection assistant and online traffic light information technology. The intersection assistant aims to help to avoid side-impact collisions, or reduce their severity, where lanes merge and at intersections. Radar sensors and a wide-angle video camera scan zones to the front and sides of the car. If the system detects a vehicle approaching from the side and assesses it to be critical, graduated warnings are displayed in the Audi virtual cockpit.
Online traffic light information is a technology that connects the Audi TT offroad concept via the cell phone network to the central traffic computer, which controls the traffic light systems in the city. Based on the information from this system, the Audi virtual cockpit shows the driver what speed to drive in order to reach the next traffic light while it is green. The cockpit displays the time remaining when waiting for the light to turn green.
