WEBVTT - Could anti-lock brakes detect a flat tire?

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<v Speaker 1>Welcome to brain Stuff from how stuff works dot com

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<v Speaker 1>where smart Happens, Hi and Marshall Brain with today's question,

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<v Speaker 1>could an anti lock braking system detect a flat tire

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<v Speaker 1>in a car? And anti lock braking system is a

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<v Speaker 1>system that helps the driver to avoid skids during panic stops.

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<v Speaker 1>In a car with normal brakes, all four wheels will

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<v Speaker 1>lock and cause the card to skid if the driver

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<v Speaker 1>jams on the brakes in a panic situation. The problems

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<v Speaker 1>with skidding our first, the car will actually take longer

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<v Speaker 1>to stop. In second, the driver loses all control of

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<v Speaker 1>the vehicle. And anti lock braking system lets a computer

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<v Speaker 1>monitor of the wheels. If one of the wheels locks,

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<v Speaker 1>the computer compulsed the brake on that wheel, so the

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<v Speaker 1>wheel keeps spinning a little bit. Because the wheels continue

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<v Speaker 1>to spin, the driver can continue to troll the car

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<v Speaker 1>with the stirring wheel. The computer census rotation using a

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<v Speaker 1>rotation sensor on each wheel. If the computer were programmed correctly,

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<v Speaker 1>and if there were a light on the dashboard, then

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<v Speaker 1>the computer could detect a flat tire and warn you

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<v Speaker 1>about it. What the computer could do is look at

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<v Speaker 1>different rotational speeds for one out of the four wheels,

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<v Speaker 1>a flat tire would spin faster than a properly inflated tire,

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<v Speaker 1>so the computer would look for one tire spinning faster

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<v Speaker 1>than the other three on average over the course of

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<v Speaker 1>a period of time that it could warn the driver

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<v Speaker 1>by activating the light on the dashboard. There are several

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<v Speaker 1>production cars that use this technique, starting with two thousand

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<v Speaker 1>six models. The National Highway Transportation Safety Administration requires that

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<v Speaker 1>all cars have some kind of tire pressure monitoring system.

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