"We covered 200 kilometres in one day and the test turned out well. We're really delighted," said Linda Wahlström, project manager for the SARTRE project at Volvo Car Corporation.
A road train consists of a lead vehicle driven by a professional driver followed by a number of vehicles.
The vehicles drove at 85 kilometres an hour, with a gap between each vehicle of just six metres.
Building on Volvo Car Corporation's and Volvo Technology's already existing safety systems - including features such as cameras, radar and laser sensors - the vehicles monitor the lead vehicle and also other vehicles in their immediate vicinity.