posted 2 years ago

Driverless Cars Could Cut Traffic Delays, Study Concludes

Results of computerised, autonomous vehicle, traffic simulations revealed for major and urban routes in the UK.

Computer simulations explained

Driverless cars could significantly reduce journey times and delays, Department for Transport research concluded. Scientists created computer-based virtual routes that enabled them to replicate a wide range of potential, real-life, traffic scenarios of the future. A notable variable was the percentage of driverless vehicles relative to the traditional, non-autonomous, alternatives.

Simulated Route A included sections of motorway, A-roads, major intersections (free-flowing), major intersections (controlled) and opportunities for traffic to merge and diverge. Route B, in contrast, was a more urban route. It included urban A-roads, signalised junctions, pedestrian crossings, and priority junctions. 

For Route A in peek periods, scientists concluded the flow of traffic barely improved when the percentage of traditional cars outnumbered autonomous cars 75%, to 25%. That was a contrast to when autonomous vehicle numbers hit 100%. Simulated journey times were then slashed by more than 11%. Delays were cut more than 40%. 

For Route B in peek periods, benefits were observed even when the percentage of autonomous cars was 25%. Scientists said that journey times were cut by 21%. Delays, in contrast, were cut more than 12%. 

Transport Minister praises autonomous vehicles

Transport Minister Johns Hayes said: “This exciting and extensive study shows that driverless cars could vastly improve the flow of traffic in our towns and cities.” There could be: “Huge benefits to motorists such as reduced delays and more reliable journey times.”

He added: “Driverless cars are just one example of cutting edge technology which could transform the way in which we travel in the future - particularly in providing new opportunities for those with reduced mobility. This study reinforces our belief that these technologies offer major benefits and this government will support their research.”

How autonomous cars could improve traffic flow

In theory, driverless vehicles could improve traffic flow via a series of characteristics and innovations. They might, for example, travel in far closer convoy than traditional, non-autonomous, vehicles as they require less thinking time - and therefore less overall stopping time - to respond to hazards such as runaway pets. 

If the typical gap between vehicles falls then more might fit into the same space. On this basis, a stretch of road that simultaneously supports 10,000, non-autonomous, vehicles travelling at their safe distance might support 12,000 autonomous equivalents.

Furthermore, driverless vehicles might more easily maintain consistent cruising speeds to help smooth the flow of traffic. Motorists, in contrast, fluctuate. Such cars might also connect to external, constantly updated, map and traffic information then choose routes that avoid the consequences of mishaps and roadworks.