An autonomous cars fleet running on roads has been found to improve traffic flow by at least 35%, according to a report by scientists from the University of Cambridge.

Researchers programmed a small fleet of miniature robotic cars to drive on a multi-lane track and observe the patterns of traffic flow when one of the cars came to a halt.

Similar to a real-world scenario, any vehicle behind the stationary car had to stop or slow down and wait for a gap in the traffic. Subsequently, a queue formed behind the stopped car and overall traffic flow slowed down.

As soon as one car stopped in the inner lane, it sent a signal to all other vehicles. This process led to all cars communicating with each other and driving cooperatively.

Subsequently, cars slowed slightly that were in the immediate vicinity of the stationary vehicle. They also allowed cars in the inner lane to quickly pass the stopped vehicle without requiring them to stop or slow down significantly.

Furthermore, the report observed that when a human-controlled driver was put on the ‘road’ with the autonomous cars and drove deliberately carelessly, other vehicles were able to adjust to avoid the reckless motorist.

St John’s College undergraduate student Michael He designed the algorithms for the experiment. He said: “Autonomous cars could fix a lot of different problems associated with driving in cities, but there needs to be a way for them to work together.”

Downing College undergraduate student Nicholas Hyldmar designed much of the hardware for the experiment. Hyldmar added: “If different automotive manufacturers are all developing their own autonomous cars with their own software, those cars all need to communicate with each other effectively.”

The outcome of the study will be presented at the International Conference on Robotics and Automation (ICRA) in Montreal.

It is intended to lead the way for new studies on how self-driving vehicles can communicate with each other, and with cars controlled by human drivers on real roads in the future.