No accident, no road repair, why is there still a traffic jam?

There is no mysterious force that causes traffic jams! Just its name like that.

When you drive on a wide highway, you think that if there is no accident, there is no construction site in the middle of the road, there are no red lights, the road will be clear. But alas, aren't we all wrong? The road is still stuck. Even if it was a short time, it only took a few minutes at a time and the car would run again like nothing had happened.

The image of the traffic jams we often see.

Why so?

Several groups of different researchers have used mathematical calculations with practical tests to answer this difficult problem. And they think they have found the final answer. And fortunately, they also suggest that they are always corrected.

They call it traffic jams ma - phantom traffic jam.

Why did the ghost block rule form?

If a highway had a sufficient number of vehicles, anything that prevented the drift of this vehicle flow would cause a continuous reaction : a car suddenly braked just a little bit, the car immediately followed will have to brake to avoid collision, and so the trend of brakes spread along the road.

'These traffic waves are born from disturbances in a steady flow of cars on the road, such as a pothole, a driver suddenly braking because of something' , Benjamin Seibold, home mathematics at Temple University, studying ghost traffic problems with many of his other colleagues.

A chain reaction is no different from the domino troops falling down.

Even if the traffic vehicle escapes from this wave of propagation, the wave itself will not disappear anywhere: it will bounce back along the direction of the traffic.'Usually this phenomenon takes place in the distance from 100 to 1000 meters, and often starts with cars in the top meeting the east road and decelerating to merge into new traffic lanes , ' Seibold said. 'And right after that moment, the car began to accelerate again as usual'.

He and his colleagues developed the concept of defining these traffic waves , calling them jamiton - a pun with 'jam' as a traffic jam, the tail -iton part taken from soliton, a kind of wave Single in math and physics has the characteristic of maintaining its shape when transmitting at a constant velocity. Using computer algorithms to simulate traffic jams, they determined what the 'jamiton' was.

Japanese researchers have also built a realistic test model and also made similar conclusions. In one of these trials, 22 instructed drivers ran at a constant speed (30km / h), keeping the distance between the vehicles unchanged, driving in a circle. And suddenly, that traffic wave appeared:

Actual tests show how traffic waves form.

So who is at fault to create these 'ghost' traffic jams?

In a way, it is possible that the driver surrendering will be the person responsible for creating these ghost lines. The actual test in the video above shows that when a driver stops suddenly in the middle of the road to avoid colliding with the vehicle in front, they will create a chain reaction that causes the series of cars to stop and cause traffic jams.

'If traffic participants pay attention to the east of the road in front of them, they will release the gas sooner so that the car slowly slows down - instead of using the brakes at the last minute - to avoid traffic jams' , Mr. Seibold said.

Computer scientist at Massachusetts Institute of Technology, Berthold Horn, has a different perspective on this issue. That is to keep the distance between your vehicle and the vehicle in front and behind, thus avoiding unnecessary braking.

When a line of roads has reached the limit of the number of vehicles circulating, the traffic junction will take place.

But actually, changing the way to control the car on the highway doesn't really completely eliminate the traffic jam, just minimizing its chances of forming a bit. It does not depend on the driving style of each driver or whether they pay attention to the road, because when a road has reached the limit of the number of vehicles circulating, the traffic junction will take place.

'I often blame a certain driver,' Seibold said. 'But the experiment shows that even though all drivers run all the same, no one makes a mistake, the traffic waves will still go on.' So it is not anyone who obstructs this ghost line, it is just because the road is too crowded.

Solution for this traffic jam

To solve this problem in the short-term, engineers have solutions to minimize this type of blockage.

The more straight the road is and the more flat, the lower the traffic jam rate , because drivers will have less braking before meeting potholes or bends. Most highways are built to be as straight as possible, so we must try to maintain and maintain the roads well in order to avoid traffic jams.

Every vehicle will comply with the speed limit, will slow down and have a certain ratio, traffic waves will be annihilated.

Another new alternative, according to Mr. Seibold, is to create more types of speed limits , this solution has been applied in some places in the US but only used primarily for things. Control vehicle speed in different weather conditions. They will use the LED lights to announce the speed required for vehicles to travel, calculating how that speed will be less likely to cause the best traffic jam. Every vehicle will comply with the speed limit, will slow down and have a certain ratio, traffic waves will be annihilated.

The final solution is completely modern: it is a self-driving car . Because the vehicle system can calculate a suitable speed, based on road conditions, data on the distance of the traffic situation to set the car to run at a suitable speed. In this regard, they are certainly more than us.

A car in surrender suddenly stops, this signal will be sent to the vehicles behind so that at the same time, the cars can simultaneously slow down, the ghost road will no longer happen. In theory, when the road is so smart, the traffic flow will flow smoothly.