Contractors in China are using a fleet of unmanned road pavers and rollers to build the Panzhihua-Dali Highway between Sichuan and Dali provinces.
The machines use GPS positioning systems, microwave communications, millimetre wave radar and other sensing equipment to find their way along.
Vehicles are coordinated remotely from a monitoring data centre, reports state news agency, Xinhua.
Bridges and tunnels account for around 81% of the highway, which has high specifications for smoothness of pavement.
The technology was developed by machinery manufacturer Xuzhou Construction Machinery Group (XCMG), Sichuan Railway Investment Group and Tsinghua University.
Researchers from the university developed the "brain" of the unmanned driving system.
One of them, Liu Tianyun, told Xinhua that China’s Ministry of Transport issued a guideline in May to advance road building techniques with 5G communications, high precision positioning, and computing power.
The aim is to save on cost and increase productivity.
China spent more than $225bn on road construction in the first 10 months of 2019.
"With the help of 5G network’s ultrafast connectivity and low latency, we are expecting more unmanned intelligent construction sites in China," Liu said.
Researchers said the machines can be guided with three-centimetre accuracy.
Image: Shanghai interchange (Denys Nevozhai/Unsplash)