Priority – Smart Safety Solutions, Smart Roundabout

Right-hand priority - worst traffic rule

1. Safety

I’ve always wondered how the priority of passing through intersections was established, by democratic vote, or by flipping a coin? This rule defies logic!

You may remember that in the past and in roundabouts the right-of-way was for vehicles coming from the right, for vehicles entering the roundabout. The result of this rule was the total blocking of roundabouts. Someone analyzed what was happening, analyzed the logic of flows and fluidity, and subsequently changed that rather uninspired rule.

How is that right, right-hand or left-hand priority?

Those who established the right of way rule probably looked at such an intersection without analyzing the logic of the right of way, the physics of things, and the dynamics of movement, and established that the right of way applies to those coming from the right.

TOTALLY WRONG!

In this intersection doesn’t matter if the priority is right or left, but unfortunately not all intersections intersect at 90° like this one.

Look at the following image:

At this intersection, what should be the right of way?

If you already have a driver’s license, you will say that the car has priority, because that’s what you learned at driving school and because that’s what the legal rules say.
The problem is that right now we are at the point where we can witness a collision between the truck and the car.

The driver of a commercial vehicle without rear windows has native visibility ahead through the truck’s windshield.

Behind, through the rear-view mirrors, the driver has visibility of approximately 15-20° on either side of the truck.

Turning the head to the right at 90°, the driver has visibility on the right side only as far as the right door window allows.

By turning the head to the left 90°, the driver has visibility on the left side only as far as the left door window allows.

But he has the ability to stick his head out the window to get a view of the entire left side of the truck.

But on the right side of the truck, behind the glass on the right door, the driver no longer has any kind of visibility, this being a blind spot.

It is physically impossible for the driver of a commercial vehicle to secure himself from the right side from this angle.

The car and all vehicles coming from the right behind will not be able to be seen by the truck driver.

The driver of the car knows that he has priority and will continue his journey.

While the truck is moving, the car will reach the intersection, at which point the accident occurs.

However, the right of way for vehicles coming from the right is found in many intersections, both in controlled intersections, where the priority of passage is established for the road on the right, where the car is, and in uncontrolled intersections, where right-hand priority applies.

All drivers who will have to give way to vehicles on the right, at a sharp angle to the vehicle they are driving, risk causing a traffic accident and also risk the repercussions of the law.

Although the truck driver is physically unable to secure himself from the blind spot, in the event of an accident, he will be considered guilty according to the law, for not giving priority. They are the blameless culprits.

I see accidents like this every day and although I have suggested to the local authorities to change priorities in a few intersections, no one seems to understand the gravity of a road architecture that defies logic. Sometimes I feel like I’m living in the movie Don’t look up!

The traffic rules must ensure the 2 objectives: Safety and Fluency!

Right-hand priority does not provide safety either in controlled intersections or in uncontrolled intersections!

In the case of the general priority on the left, the truck driver would have stopped, secured himself properly and given priority to the car, because he has visibility on the entire necessary spectrum.

Right-hand priority is logical and makes sense, only for countries where vehicles drive on the left side of the road.

2. Fluidity

The four streams of cars arrive simultaneously at this intersection. The yellow car stream must give way to the blue car stream. The blue car stream must give way to the green car stream. The green car stream must give way to the red car stream. And the red car stream must give way to the yellow car stream.

In the next second, the entire intersection is blocked. Every stream of traffic has blocked the left flow and it appears to be a dead end situation.

This is what happens now, when the priority for those on the right is the rule and the legal solution.

Everyone is stuck and no one can get out of the intersection.

If we want fluidity in intersections, we should see the fluidity of liquids, because that’s where the name fluidity comes from. If we can see the intersection as a container of water, as a sink we will be able to analyze the fluidity. Cars enter and exit the intersection, water enters and exits the sink. If the sink outlet is free, the water drains smoothly, as much water goes in, as much water goes out, as long as the outlet is free.

But if we block the outlet, that is, the water drain, then the sink will fill up without the outlet being able to be used. So we will have a blocked intersection that will be filled with cars, which cannot use any exit from the intersection.

So if we want to unblock the intersection, we have to unblock the drain, remove the plug. The same happens in intersections. If we block the exits, we block the intersections.

To unlock them, it is necessary to give up to the right-hand priority, which is a stopper for fluency, and to adopt the left-hand priority, which provides not only safety, but also fluidity.

Now, the blue car stream must give way to the yellow car stream. The green car stream must give way to the blue car stream. The red car stream must give way to the green car stream. The yellow car stream must give way to the red car stream.

If something is still not clear to you, put a coin in the center of the intersection and apply the roundabout rule.

Now cars only have to give priority when entering the intersection, and further, once inside in the intersection they have clear exit.

Priority for those on the right does not provide safety either in controlled intersections or in uncontrolled intersections! From now on, traffic is now flowing, without blocked intersections!

So, logic, physics and geometry should be the deciding factor in the rule of priority, and I hope that the irrational rule of priority for those on the right will be replaced as soon as possible by the general rule of priority for those on the left, and thus, all intersections from the world, controled or uncontroled, to receive, through national legislation, logical norms that present safety for traffic. A European Directive would be welcome, considering the inertia of the states to change, the bureaucracy and sometimes the degree of (in)competence of the specialists responsible for road safety.

Some will say that it would be impossible to make this change, because drivers would be confused and the measure would be unsustainable. Well, Sweden changed the traffic from the left side to the right side of the road on H-day, September 3, 1968. Things were confusing for a few days, there were drivers who went the wrong way and went on the wrong side, but the things returned to normal in a short time.

So, logic, physics and geometry should be the deciding factor in the rule of priority, and I hope that the irrational rule of right-hand priority will be replaced as soon as possible by the general rule of left-hand priority, and thus, all intersections in the world, controled or uncontroled, to receive, through national legislation, logical norms that present safety for traffic, but also fluency.

France discovered the importance of blind spots and made a correct but insufficient decision. By Decree no. 2020-1396 of November 17, 2020, France obliges commercial vehicle drivers to mark the driver’s blind spots on their vehicles.

It is a warning and awareness measure for road users, but right-hand priority continues to cause damage, victims and innocent culprits. An important European tourist landmark, in the Arc de Triomphe square in Paris, traffic is circular, without being a roundabout, and those entering the square from the right have priority!