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Only 5k's over, what difference could it make?

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You never know what other drivers might do.

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[ CAR CRASHES ]

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We're at the Monash University
accident research centre in Melbourne.

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This is the driver simulator, we have a full 180
degree view including some rear views as well.

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The simulator studies are quite interesting
from an engineering point of view

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because what we're looking at are
the human factors around driving.

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We're trying to think about
why people do what they do.

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We look at the difference between 65
kilometres an hour and 60 kilometres an hour.

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It's quite common for people to think
that just a small amount of speeding

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over the speed limit is not significant.

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I think people don't understand the maths
inherently, we don't necessarily feel the maths,

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I suppose you can put it, and I think most
people underestimate the importance of speed

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and how much small increases in speed can
make a big difference in stopping distance.

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And just by the use of simple mathematical
equations we demonstrated that the significance

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of a 5 kilometre an hour difference
in initial speed translated

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to 27 kilometre an hour difference
in the final impact speed,

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because of the way the maths works.

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It is fairly simple maths, the equation is
simply V squared equals U squared plus 2ax.

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V squared represents the
square of the final speed.

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Now for the purposes of stopping distance
we usually just let that equal zero,

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because we are assuming that
we want the car to stop.

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So we end up with U squared plus 2ax
equals zero and by rearranging that we end

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up with the equation d is equal
to U squared divided by 2a.

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So what that means is that the
stopping distance is proportional

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to the square of the initial speed.

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For a doubling in initial speed the stopping
distance will increase by a factor of four.

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For a tripling in initial speed so say from 20
kilometres an hour to 60 kilometres an hour,

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the stopping distance will
increase by a factor of nine .

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So that's where the maths is showing
us how important initial speed is

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for stopping distance The thing that people
should remember is most of the stopping is done

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in the last few metres because you're
still taking off speed at the same rate

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but you're doing it from a much smaller base
so you've already taken off a lot of speed,

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those last few kilometres an
hour drop away quite quickly.

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By having a lower speed, initially you'll
be able to get into that lower part

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of the curve more quickly as well, and
therefore wash off the speed that's required.

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At Holden we're about to
introduce forward collision alert,

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which is designed to alert a driver when
they're travelling too close to the vehicle

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in front using a math algorithm
behind all of that.

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Maths and physics, are the building
blocks to determine when we need

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to help our drivers for safe stopping distances.

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Generally people don't drive as though
they're waiting for something to happen.

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Often people are thinking about other
things and every second that time increases

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at 60 kilometres an hour you travel
another 15 or 16 metres down the road

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and that could mean the difference between
stopping in time and not stopping in time.

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Three seconds could save a person's life.

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So whatever speed you're doing, do the maths.