We’ve all had the unfortunate pleasure of being stuck behind the tentative highway driver – the one that pumps the brakes during any lane change, when a semi-truck passes them, or even at the sight of a car in the breakdown lane miles ahead. Riding the brake on the highway has a detrimental effect on the flow of traffic – creating a brake-light-chain-reaction slowing the pace of free-flowing traffic. As one would expect, with literally no provocation to pump the brakes accept one car slowing down, the free-flowing traffic slows down considerably due to collective braking. Now think about how an autonomous self-driving vehicle would react to sudden braking on the freeway.


The University of Illinois Traffic Study

With a growing list of next-gen electric luxury vehicles featuring autonomous technology and the ever-present discussion surrounding the safety of self-driving cars, the University of Illinois at Urban-Champaign conducted a rather groundbreaking traffic study. Hoping to prove that incorporating a single autonomous vehicle into a line of 20 cars would alleviate congestion, University of Illinois researchers led by Daniel Work put together a phantom traffic demonstration. The results were fascinating:

1. The presence of just one autonomous car reduces the standard deviation in the speed of all the cars in the jam by around 50%.

2. The number of sharp hits to the brakes is cut from around nine per vehicle for every kilometer traveled to at most 2.5 – and sometimes zero.

“A single autonomous vehicle can control the flow of at least 20 human-controlled vehicles around it, with substantial reductions in velocity standard deviation, excessive braking, and fuel consumption.”

AV’s Revolutionizing Traffic Flow

The autonomous vehicle’s ability to control its speed intelligently during the slowdown, in essence, stopped the braking chain reaction further down the line. This also has a positive impact on fuel consumption. The process of slowing down and then speeding back up again (especially on the highway) has a negative impact on your miles per gallon. According to the study, the presence of autonomous cars has “a savings as much as 40% when averaged across all the cars in the traffic flow.”
What’s even more fascinating about the study, the autonomous vehicle used in the traffic circle simulation did not use state-of-the-art self-driving technology engineered in today’s Best Electric Cars. It was nothing more than advanced cruise control system standard in most premium sedans.

“This simple structure implies that a noticeable impact on congestion traffic flow can in principle be achieved by means of adaptive cruise control system that are already in place in certain new vehicles.”

Tesla’s Self-Driving Technology

On the heels of the University of Illinois study proving that “AV’s counteract humans’ tendency to produce unstable traffic situations,” electric vehicle manufacturers on the fence about incorporating state-of-the-art self-driving technology should have all the evidence they need to move forward. With Tesla’s newest fleet of electric vehicles (Model X, Model S, or Model 3) all equipped with the latest self-driving hardware and competitors like the Chevy Bolt EV and BMW i3 reluctant to integrate the auto-pilot feature, it’s safe to say that Tesla’s investment into self-driving technology certainly looks like it’s going to pay off.

Sources: MIT Technology Review, University of Illinois