One of the world’s most famously gridlocked cities in the world may be about to shed its image and get on the move again.

Los Angeles in California has just finished installing $400m of technology to synchronise its traffic lights. The Automated Traffic Surveillance and Control system uses an array of cameras and sensors in the road to measure traffic flow, and a centralised computer system to make constant tweaks and changes to the city’s 4,400 lights to keep traffic running as smoothly as possible. In theory, it is now possible to cross the city without ever stopping.  

“By schronising our traffic signals we will spend less time waiting, and less time polluting,” says Mayor Antonio Villaraigosa.

The system, which was started in 1984 when Los Angeles hosted the Olympics and has taken until now to finish, is estimated to increase travel speeds by 16% and cutting journey times by 12%.

The figures are impressive, but other congested cities looking on in envy may do well to wait a few more years before rethinking their own traffic systems. While the LA system may seem cutting edge now, it could seem as outdated as a traffic officer guiding traffic with white gloves in a few years time. That is because engineers are planning a radical rethink of our streets that will change just about every aspect of how we drive – including who is in control of the vehicle.

Car talk

In this new world, cars are packed nose to tail travelling at speeds in excess of current limits. They weave their way through unmarked junctions, with no traffic lights. Lane markings are non-existent, and stretches of road switch from being one-way in one direction, to the opposite, with no warning. Perhaps most alarming of all, very few of the “drivers” have even passed a driving test.

It may sound like an impossibly chaotic scene, where accidents are inevitable. But this is one future based on predictions about the uptake of autonomous cars.

In the United States the Instititute of Electrical and Electronics Engineers (IEEE) predicts that driverless cars will account for 75% of all vehicles on the roads by 2040. Vehicles, such as Google’s self driving car,  are already leading the way.  And small-scale trials of linked-up roads are being conducted in some cities

Far from being pandemonium, “intelligent” vehicles running on an intelligent road network have the potential to smoothly synchronise traffic, eliminating gridlock and accidents forever.       

In this new world, information flow will govern traffic flow. Vehicles will be much more aware of their own positions and those of the vehicles around them, and will not rely on crude coloured lights to tell them when to stop and go.

“In the future smart intersections may not need lights,” says Azim Eskandarian, director of the IEEE’s Center for Intelligent Systems Research.  “These intersections will very efficiently harmonise and synchronise speeds in one direction, and then the other.”

So-called vehicle-to-infrastructure (V2I) communication will allow cars to share their the route they plan to take, their destination and current position with a central command center – like a supersized version of the one running LA’s streets.

The groundwork for this is already being laid in the US by the Vehicle Infrastructure Integration Consortium, a group of car manufacturers trying to develop specific applications and protocols for a system. And just outside Detroit in the town of Ann Arbor, there is already a pilot project that has equipped 29 intersections with instruments that allow a team of researchers to direct traffic lights in order to make the traffic move more efficiently.

The hub of the future will take this to an extreme - accumulating all the data across a metropolis and plan traffic loads and optimise routes accordingly. It will also send commands back to the vehicles about when to safely enter an intersection, and what speed to hold to minimize stop-start driving.

Meanwhile the cars will also talk to each other, using vehicle-to-vehicle communication, constantly checking their environments and positions relative to other cars around them.

Vehicle-to-vehicle communication is already in development.  In 1999, the United States Congress set aside a region of the 5.9 GHz radio frequency band – already used for wireless – specifically for the purpose. And a host of manufacturers are already developing applications.

The trial being run in Ann Arbor also points towards the type of application that could become standard. For example, drivers get an audible warning if they try to change lane with a car in their blind spot, or if the car in front of them brakes hard and the driver doesn’t seem to notice. The car can also give warnings at blind corners and junctions that another vehicle is about to pull out.

“When multiple vehicles are communicating with each other, when there is slowing, there is plenty of time to communicate that to cars behind so they can start braking earlier,” says Professor Eskandarian.

This type of communication, he says, “will really solve a lot of the problems” that result in severe crashes.

No licence, no problem

Cars that talk to each other can also match their speeds, and drive more closely together without risk of the car in front suddenly braking. As a result, many envisage the idea of “car platooning” that will link together cars on high-speed highways to travel faster, more safely, and using less space. Various trails of this technology are already taking place, with one of the most advanced run by an EU consortium called Satre, which demonstrated trains of vehicles travelling at speeds of up to 90km/h sometimes travelling just 4m apart. 

Lane markings will be unnecessary when cars can accurately determine their own position using an inbuilt array of sensors, radar and laser-range finders, meaning a much more fluid use of road space. Currently, some cities dedicate lanes on busy roads or bridges to funnel traffic into the city in the morning rush hour, and out of the city in the evening. In the future the changeovers could happen more quickly and more often to dynamically adjust to traffic flow.

Rebuilding  and redefining the road infrastructure may also brign with it new opportunities. For example, researchers at Stanford university in the US have been experimenting with roads that continually charge electric cars as they drive along. The system uses magnetic coils buried in the road that automatically couple with another coil on the bottom fo the car. Such arrays could be built into future roads as they are wired up to the sensors and systems they will need.

Finally, these new roadways could also allow mixed use roads, allowing trains and trams to easily share information between them, allowing them to cohabit on the roads.

As a driver, this new system may sound horribly confusing. But, perhaps the most radical prediction about the rise of these new roads is that humans will barely do any of the driving. Instead, we will be asked to put our faith in the system.

“What will a driver’s licence mean?” asks Prof Eskandarian.

“All you need is to be able to operate something like a GPS to input your origin and destination, and the rest will be taken care of autonomously. We don’t need a pilot’s licence to ride on an aircraft.”

Asking people to trust the technology will be a huge obstacle. But it is not the only bump in the road. The cost of this infrastructure will be significantly higher and will require huge investment form governments.

But Prof Eskandarian believes it will slowly creep into everyday life.  First of all, we may see a single lane dedicated to autonomous vehicles, the way they currently are for busses or carpools. At the same time cars will gradually become more and more intelligent, sharing more and more information with each other and the road around them. Then decades from now, the road system will be indistinguishable from the one we drive on today.  

Perhaps they will come just in time to stop Los Angeles grinding to a halt again. 

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