who commute to work alone, chances
are you've had a commute like this.
Stop -and -go traffic, bumper-to -bumper
with no end in sight.
And when you finally reach the end
and the road clears up, you realize
there was no reason for traffic to
be stopped in the first place.
Experts call them
phantom traffic jams.
Those moments when traffic grinds to
a standstill for no apparent reason.
Quite often I find myself thinking, oh,
there must be an accident a few
miles ahead or there's someone who is
blocking the left lane or something.
And it's unfortunate that it's
actually not that simple.
These traffic jams are often caused by
a car that slows down during heavy
traffic—to check a phone, sightsee or
tend to screaming kids in the
backseat. And the resulting chain reaction is
like a ripple in a pond, and
that causes a ripple effect that can
slow down dozens of cars behind them.
At some point, the car in the back of
the ripple is forced to come to a
complete stop. Traffic comes at a big
cost in both time and money.
A new study found the average urban
commuter spends about 54 hours each
year in traffic.
It also costs the U.S.
economy a grand total of $179 billion
each year, according to the Texas
A&M Transportation Institute.
Here's how traffic jams like these formed
in the first place and what's
being done to make
them more bearable.
First, let's take a look at
how a phantom traffic jam starts.
It begins with just two
cars traveling on a highway.
When the first car has to use its
brakes for one reason or another, the
car behind it has to react.
And it also slows down.
When you expand this to multiple cars,
i t creates a chain reaction where
everyone has to slow down or
come to a complete stop.
Clearly, the person at the front of
the traffic jam is the problem.
Well, it's not exactly that clear.
According to the Institute for
Electrical and Electronics Engineers,
traffic jams could be the result of the
car in front slowing down and how
the car behind it reacts,
what it calls bilateral control.
Here's how they explain it.
When the car in front hits its brakes,
the car behind it doesn't slow down
at the same rate. It takes a second
for the driver of the second car to
react. And they often have to
break harder than the first.
Meaning the car slows down even more.
Then the car behind it has to do
the same, braking harder, on and on,
until eventually the cars further back have
to come to a complete stop to
avoid a collision. Likewise, when the car
in front speeds up again, the
car behind it doesn't speed up
at the exact same time.
It takes a moment for the driver to
move from the brake pedal to the gas
pedal, meaning it takes longer
for them to speed up.
This in theory prolongs the traffic jam
and this is a dynamic system where
every vehicle is doing the right thing,
namely following the one in front
of it, which seems logically
the right thing to do.
But if they are all doing that, it
turns out that you will get these
increases and decreases in
speed and density.
And if those fluctuations get large
enough, then you can stop-and -go
traffic. You know, we're
all familiar with that.
So what's the cost of all
of this time spent in traffic?
According to the Auto Insurance Center,
there are around 250 million cars
traveling on America's roads.
That's up 20 percent
from a decade ago.
That same auto insurers group found the
average driver on one of the 10
busiest routes in the nation spends about
140 hours in traffic each year.
That's nearly six full days.
But your personal time isn't the only
thing at stake in traffic jams.
According to the EPA, a typical
passenger vehicle emits about 4.6
metric tons of carbon
dioxide every year.
And it's a health issue, too.
A 2008 study from Zuyd University
in the Netherlands found exposure to
diesel exhaust could have an impact
on the brain, particularly in the
parts that deal with
behavior and personality.
It's been linked to heart
disease, respiratory issues in cancer.
Exhaust may also cause brain cell
damage and elevated autism rates
according to studies with mice.
Then there's the money wasted.
The Texas A&M Transportation Institute
reports that congestion cost per
commuter in 15 of the largest U.S.
metropolitan areas is $1580 dollars.
All told, traffic congestion
wastes an estimated 3.3
billion gallons of fuel
and costs each U.S.
commuter more than $1000 a year.
So is there anything individual drivers can
do to alleviate the traffic on
their commute? There's actually a traffic
jam etiquette, according to the
Auto Insurance Center, and a number of
things drivers can do to help ease
the problem. The first recommendation
is to acknowledge other drivers.
You may even want to turn on
your hazard lights to warn vehicles behind
you that you're
approaching slower traffic.
Don't tailgate. Leave more space to allow
you to slow down instead of
stopping. So traffic can keep moving.
Bilateral control does the kind
of illogical thing of saying.
Look behind you as well.
And so in addition to just looking at
the distance to the car front, look
at the one behind. And the simple version
of it is try to equalize the two
distances, trying to stay in the middle
between the car in front and the
car behind. One of the side effects
of that behavior is you won't be
tailgating. Don't use
your cell phone.
It's illegal in most states, and
regardless, you'll likely anger other
drivers who see you're
not paying attention.
Don't use the expressway shoulder.
Drivers might not see you coming, and
police often lay in wait for drivers
who see it as a faster route.
Lay off the horn. Venting your frustration
with a car horn will only serve
to irritate other drivers.
Use the zip merge technique when
traffic is merging, two lanes merging
into one can keep both lines moving.
If everyone allows a park to join
the lane in front of them.
And finally, use traffic reports or
apps to find alternative routes.
Waze and Google Maps provide live
traffic updates as well as alternative
routes. There are a lot
of cars out there.
Following the rules and being considerate of
others is one way to keep
traffic moving. But unfortunately, not all
drivers are going to follow
these rules. So is there another way
to end traffic jams for good?
Equal spacing between vehicles is the
best way to prevent traffic jams
before they start. And that's sort of
at the heart of bilateral control.
Yes, if you have disturbances, they
will affect the neighboring vehicles,
but the effect dies down rather than
increasing the further you go, which
is what happens in car-following.
However, no matter how good a driver
someone is, they can't move in
perfect time with the car in
front of them and behind them.
But autonomous cars could.
Autonomous cars use sensors and wireless
tech to keep your car about
halfway between the car in front and
the car behind and maintain perfect
bilateral control.
More than 40 companies are
currently working to develop autonomous
vehicles, according to CB Insights.
Virtually every major auto manufacturer
has self-driving cars in
development and some have partnered with
Silicon Valley in the process.
Tesla CEO Elon Musk, ever the optimist,
claims his company will have a
fully autonomous vehicle by
the end of 2020.
But John Krafcik, CEO of self-driving
car tech company Waymo, said in
September 2019 that there's still
a long road ahead.
Fully driverless vehicles may still be
a ways off, but MIT's, Berthold
Horn says newer cars with adaptive
cruise control and current self-driving
tech could be adapted to
keep proper spacing between vehicles.
And it could be done
in just a few years.
But the good news is that cars
with adaptive cruise control have almost
everything you need to
implement bilateral control.
And so since more and more cars do
have that, you know, we're at a good
time. This this is the
time to implement it.
And so the only addition is you
need to have sensors out the back,
obviously, in addition to
the ones in front.
Horn says under normal driving conditions,
you may get around 1800 cars
per hour, per lane of throughput.
The Federal Highway Administration defines
throughput as the number of
distinct vehicles that enter and exit
a highway system during a particular
period. He believes that number could
be doubled with bilateral control
and that could buy time, he says,
until autonomous vehicles take over the
highways. In Hawthorne, California.
Space-X engineers are toiling
away on Musk's Hyperloop.
A low pressure tube with capsules that
are transported at both low and
high speeds throughout the
length the tube.
The capsules are supported on
a cushion of air.
The initial plan was to run a
system from San Francisco to Los Angeles,
one of the most traveled
corridors in the American West.
Not only would it mitigate car traffic
between the two cities, Musk claims
a Hyperloop would also be cheaper
than traveling by air, more cost
effective than high speed rail
and more environmentally friendly than
cars. Then there's the idea
of leaving the ground together.
Urban air mobility took another step
forward in October when a company
called Volocopter conducted a test flight
over Singapore's Marina Bay .
Uber Air promises says
aerial ride-sharing at scale.
The company plans to roll out
in Dallas, Los Angeles and Melbourne,
Australia in 2023.
Testing in those cities is
expected to begin in 2020.
So the next time you're sitting
in bumper-to -bumper traffic, cursing the
drivers ahead of you. Imagine yourself
getting to your destination via an
autonomous car, Hyperloop
or air taxi.
For now, though, you'll
just have to wait.
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