The 44th edition of the rally will start on January 1st and for the third consecutive time it will take place entirely in Saudi Arabia. At the start there will also be low-emission vehicles including the Audi RS Q e-tron, the electric range extender developed in record time for the Dakar 2022
Shortly before the Dakar 2022, the 44th edition of the rally kicks off on January 1st, which for the third consecutive time will take place entirely in Saudi Arabia, thirteen stages in the desert sands with start and finish in Jeddah. The protagonists will be motorcycles, cars and trucks, the novelty of this edition is the participation of some low-emission vehicles that represent the vanguard of the project which aims to involve only very low-emission vehicles in each category in 2030. Intermediate step in 2026 with the participation of all Elite car and motorcycle riders on green prototypes. Audi’s participation in the Dakar 2022 with the RS Q e-tron, an electric prototype with range extender that brings an avant-garde technical concept to its debut in the rally raid, is placed in this context: three electric motors to move the vehicle and a thermal one to recharge the batteries, because there are no columns in the desert.
A RECORD TIME PROJECT
A car that required an extraordinary effort, as Julius Seebach, CEO of Audi Sport GmbH and Head of the Brand’s international sporting activities explained at the beginning of October: “The Audi RS Q e-tron project was completed in record time, about 12 months, and represents the maximum expression of the claim advantage through technology (At the forefront of technology) “. The first ignition of the car, which took place on 30 June 2021 at the Audi Motorsport Competence Center in Neuburg an der Donau, and the start of the Dakar in Saudi Arabia are separated by only 6 months. A demanding challenge that required a series of tests necessary to prepare the Rs Q e-tron for the extreme stresses characteristic of the Dakar such as the alternation of sand, water, cold, large gradients and the terrifying fesh fesh, the very fine dust of the desert that it creeps everywhere. The two weeks of competition include daily stages up to 800 kilometers long, which is why the House of the four rings is fielding a real “dream team” at the start. Stéphane Peterhansel, the most victorious driver ever in the Dakar, and Carlos Sainz, who has achieved three overall successes and is a world rally champion, are joined by Mattias Ekström, an exceptionally versatile driver with whom Audi has celebrated countless victories in the past. In addition to extraordinary speed performances, each of them brings unique skills and motivations. And the same goes for navigators, who play a crucial role during the competition.
THE RANGE EXTENDER TO BEAT THE DESERT
The Audi RS Q e-tron is equipped with three powertrains derived from the Audi e-tron Fe07 Formula E single-seater: two Mgu (Motor Generator Units), one at each axle, take care of traction, while a third unit acts as a generator. to help recharge the high voltage battery, especially when braking. Since it is not possible to draw energy in the desert, Audi has opted for an on-board solution: the accumulator is refilled while driving thanks to the action of a range extender. The latter function is entrusted to the high-performance four-cylinder TFSI – turbo with direct petrol injection – derived from the Dtm, the German Touring Championship. The maximum power expressed is 680 hp. The electric propulsion guarantees a remarkable speed of delivery of the MGUs, which makes the quattro electric four-wheel drive extremely precise and efficient. The transmission is single-speed and involves a simplification of the mechanics compared to competitors with traditional engines, giving up the classic transmission shaft and the central differential to the advantage of reducing the masses and the possibility of varying the strategy of distributing the thrust between front and rear.
The House of the Four Rings has developed the high voltage battery internally, in collaboration with a specialized partner. The accumulator weighs about 370 kilograms and with a capacity of 50 kWh contributes to the efficiency of the powertrain, which is estimated to be over 97%. A result to which the experience in Formula E contributes, from which derive the three MGUs on which Audi has had to intervene deeply in order to face the desert the desert. Both the MGUs and the TFSI engine require a dedicated cooling circuit, in total there are six thermal management systems on the car, also considering the intercooler and passenger compartment conditioning. No less complex are the software adopted and the electrical and electronic systems, so much so as to require two central control units and about four kilometers of cables in the car, without counting the elements of the high voltage system.
MULTIMATERIAL STRUCTURE: STEEL, ALUMINUM AND KEVLAR
A car that is about to face the Dakar must meet two needs: to be resistant and to protect the occupants. The passenger cell and the supporting structure of the Audi RS Q e-tron consist of a tubular trellis frame which, by regulation, must be made of metal. Audi has opted for hot-formed, aerospace-derived, high-strength steel “alloyed” with elements of chromium, molybdenum and vanadium (CrMoV). The tubular frame thus obtained, in compliance with the geometries established by regulation, satisfies the static compression and impact tests for category T1. Audi protects its crews by means of panels in CFRP, carbon mixed with thermoplastic polyurethane, inserted in the interstices of the frame itself and integrated in multiple points by Zylon: a thermosetting polymer that prevents the penetration of pointed and sharp objects and, at the same time, pilot fencing and navigator from the high voltage system. The seats of the Audi RS Q e-tron are also made of CFRP and are inspired by the seats used in DTM and endurance.
The only difference is the controlled deformation section in the shoulder area, imposed by the regulation. The shell structure is identical for all riders, while the high-density sponge padding and pneumatic cushions are totally tailor-made. The frame structure draws on technologies and solutions refined for decades in multiple disciplines, ranging from the DTM tubular (adopted from 2004 to 2011) to the steel sheet frame for rallycross (from 2017 to 2018) up to the CFRP monocoque for the LMP prototypes (from 1999 to 2016), passing through the most recent DTM cars (from 2012 to 2020) and the Formula E single-seaters (from 2017 to 2021). Although the circuit and the desert are apparently the polar opposite, there are multiple parallels between endurance and the Dakar, primarily in the loads to which the frame is subjected and in the g-forces detected. Depending on the components, the bodywork is in CFRP, Kevlar or a mix of the two materials, in some cases with a honeycomb structure. The windshield, derived from Audi A4, is in laminated glass with a special anti-scratch treatment, while the side windows are in polycarbonate, to the advantage of lightness. The crews can count on a wide view. The couplings between the glass surfaces and the body panels are “sealed” by means of a layer of foam material to contain dust.
THE PROTECTION OF THE ELECTRIC POWETRAIN
The high voltage system requires a high level of protection. The centrally located high-voltage battery is encapsulated in a CFRP and Zylon case. The underbody, which is subjected to extraordinary shocks in rally raids, is shielded by a complex structure: the external aluminum plate is accompanied by a layer of highly absorbing expanded foam and, to further defend the accumulator and the petrol tank, a sandwich structure in CFRP. On the one hand, the latter is called to dissipate the contact energy propagated through the plate and the foam, on the other hand, once a critical threshold is exceeded, it is designed to deform in a controlled way to protect the accumulator. The entire “plate group”, 54 mm thick, derives from the WEC world championship and can be quickly replaced during the service at the end of the stage. To complete the Audi RS Q e-tron high-voltage system protection concept, the manufacturer of the four rings adopts an ISO monitor, derived from the LMP (Le Mans Prototype), to monitor any voltage fluctuations. If an accident occurs and an overshoot kinetic load is detected, the entire system shuts down. At the same time, an acoustic signal and some warning lights along the bodywork communicate the state of danger to the rescuers. Although the Dakar develops mainly in the desert, the powertrain is shielded from water, especially in the event of a ford. And if a fire breaks out, the extinguishing system uses an electrically inert agent.
December 28 – 2:53 pm
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