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Traction Control (cont)
Both data logs are from the same event. As the driver has increased the throttle (green) in mid corner, the rear tyres (top blue) have started to spin. The TC has detected this wheel slip, and applied power reduction. This electronic process of power reduction has taken less than .072Sec or less than 2 meters. This is less than 1 revolution of the rear tyres! The driver is unaware anything happened.
By comparison, in the bottom datalog the cursor's highlight the time it takes for the driver to react and reduce the throttle setting. He has reduced the throttle, however its not enough and TC is being maintained to cover him. In this case his reaction time was .308Sec or about 7 metres after the initial loss of grip. Without TC the rear of the car would have stepped out.
The on board electronics constantly calculating a % slip aim. This valve is calculated based on road speed, gear, Vertical G, Laterial G, and the history of the past wheel slip events. The rear tyres have "x" grip, to be used in cornering, braking and acceleration or a combination. If you use more of the grip up by nailing a corner, then you have less potential power allowed to drive the car, before the wheels spin. These 3D tables take all this into account. The tables can be tuned to all road surfaces, the car's handling, and driver preferences and abilities.
