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EETE NOV 2014

When the steering wheel is a computer By Christoph Hammerschmidt One of the most demanding disciplines in motor sports is, besides formula one, the World Endurance Championship (WEC) - a series of eight races of which the 24 hours of Le Mans probably are the best known. In this race, so-called Le Mans Prototypes compete against each other through driving skills, engine power, and an impressive amount of electronic controls. Porsche is one of the contestants - and the steering wheel is a not insignificant element of what gives their vehicles the decisive edge. Each team designs its steering wheels individually, taking into account the respective drivers’ preferences. Porsche drivers have 24 buttons and switches in direct access - plus six paddles at the rear side of the wheel. The device is a proof of the quadrature of the circle in that this wheel is not circular but rather a flat rectangle. In the centre of the wheel, a large screen displays various types of information such as speed, gear currently engaged and charging status of the lithium ion battery - because the WEC racing car has a hybrid drive with an electric motor that drives the front axle and thus complements the two-litre four-cylinder internal combustion engine which drives the rear wheels. The battery status informs the driver about the amount electrical energy that can be called up to boost the overall power, for instance during passing manoeuvres. The thumb wheel in the right grip handle dims the display brightness - essential during the night. The identical wheel in the left handle sets the volume of the pit radio while the thumb wheel at the top of the left grip selects the information displayed on the screen, and its pendant at the right side varies the interval timing for the windscreen wiper. The buttons and switches on the steering wheel were carefully positioned to facilitate reliable operation at racing pace and ensuring the short reaction times. The most frequently used buttons are positioned along the top outside edge, so they are easily reached with the thumb. The blue button at the top right which is almost always in use, is the headlamp flasher, used to warn slower vehicles in the WEC field before they are lapped. When pushed once, the headlamps flash three times. In daylight, the drivers keep their thumb on it almost permanently, as the headlamp signal is more difficult to perceive at that time. Fig. 1: The steering wheel of Porsche’s WEC LE Mans Prototype car. VISIT US AT: BOOTH A21 FRANKFURT AM MAIN, NOVEMBER 18 - 20 SOLUTIONS FOR DEVELOPERS HALL B.1 - BOOTH 120 MESSE MÜNCHEN, NOVEMBER 11 - 14 16 Electronic Engineering Times Europe November 2014 www.electronics-eetimes.com


EETE NOV 2014
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