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avl racing OVERALL ENERGY AND THERMAL MANAGEMENT An integration test bed also allows you to optimize the race car’s entire regard to basic design and the specific is that the vehicle can be operated without external engine conditioning. the very same cooling systems for engine, transmission, battery, e-motors Gerhard Schagerl explains and continues: optimization process, a factor which is of major significance. This is because is one of the fields where significant increases are expected to be obtained in the future. The critical question here is how little cooling my vehicle > energy management – both with racing track. A further benefit “The race car is operated with and brakes which are also employed later on the racing track,” “As a result, these cooling circuits can be included in the the cooling system and, consequently, the aerodynamic efficiency can make do with.” The highdynamic Any elements not physically present in the setup can be simulated – just as required by the specific testing task. This includes the entire aerodynamics and the contact between the road surface and the tires. 2 6 F O C U S ventilation concept on the AVL testbed is capable of accelerating the cooling air stream to the vehicle to 360 km/h in a span of 5 seconds and decelerating down to 0 km/h within just 4 seconds. Apart from that, the air can be heated or cooled in order to simulate races in extreme climatic conditions. H2IL – HARDWARE & HUMAN IN THE LOOP Aside from optimizing the hardware, the control units are a further key focus in racing development. “The job of tuning the software to fit the different control units – engine, transmission, hybrid system and brake-by-wire – is extremely driver specific,” says Gerhard Schagerl. “Specifically it is all about how the vehicle behaves, for example when accelerating out of the curve. This is because drivers have different preferences; some prefer a vehicle with a slight tendency to oversteer while others go for a more neutral vehicle or one that is more likely to understeer. So our goal is to provide car that matches the drivers’ specific preferences – a car they can trust, and which allows them to drive at constantly high speeds.” To be able to incorporate the driver’s feedback directly into the development process, AVL is provided with a state-of-the-art driving simulator that is operated in conjunction with the complete-vehicle testbed. “We call this combination ‘hardware & human in the loop’ (H2iL). This is because, in addition to the classic hardware-in-the-loop system (HiL), the system additionally includes the human factor (the racing driver), hence the term H2iL,” Matthias Dank explains. The driving simulator allows drivers to do virtual laps in the cockpits they are familiar with. The cockpit’s operating elements installed on the moving simulator platform are connected to the real race car on the integration test bed. “This allows us to connect the two worlds as part of the integration and obtain the immediate feedback from the driver on any changes we make to the drive system or vehicle. Our development goal is to create a driving behavior which is predictable to the driver in each and every driving situation. For example, torque peaks have to be avoided whenever the e-motor is switched on. The brake-by-wire system has to be optimally tuned, too,” notes Gerhard Schagerl.


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