(Photo/Feng Xing)

Nanjing will use self-driving vehicles to sweep the roads in tunnels under the Yangtze River after the success of a pilot program.

Nanjing Public Transport Operation and Management Group, the operator of the city’s road maintenance, cooperated with a tech company in March to launch the initiative. Data of the tunnels at two places has been collected to enable the automatic road sweeping.

In the 3-month testing, self-driving vehicles completed a distance of 4,660 kilometers and worked for 1,061 hours.

According to the test, the sweeper used LIDAR and sensors to collect information, such as avoiding the obstacle correctly, and ensured a safe and precise operation.

For a job that needs two vehicles to work overnight, it can be completed by the self-driving sweeper in about four hours, a great progress of efficiency.

Also importantly, the self-driving sweeper was able to complete the task at a high quality. The use of just one electric sweeper, instead of two fossil-fuel vehicles, also means a cut of carbon emissions by 49.46 tons a year.

The group will expand the use of self-driving vehicles to perform other functions, such as washing, inspection and ferry service.