A groundbreaking platooning trial has begun in Japan – with four truckmakers participating in largely autonomous convoys.

The tests, being conducted on a public highway, sees groups of three 12-metre trucks – each with a driver at the wheel, but the trailing two operating autonomously most of the time – running about 35m apart.

Hino, Fuso, UD Trucks and Isuzu each have trucks participating in the trial and a Toyota group company is handling the project on behalf of organisations including the Ministry of Economy, Trade and Industry.

The trial, which sees the convoys driving at 80km/h on the Shin-Tomei Expressway southwest of Tokyo and the Kita-Kano Expressway north of the capital, ultimately aims to have two entirely unmanned trucks following a human-operated lead truck. The companies aim to reach this point in 2020 and launch the technology on the market as early as 2022.

This is thought to be the first public trial of convoys comprising trucks from different manufacturers.

The following trucks' adaptive cruise control systems use a combination of vehicle-to-vehicle communication, cameras and radar to measure the distance between each truck and maintain a preset gap. The closer following distances reduce air resistance and thus also reduce fuel use.

The platooning trial is part of the Japanese government's Future Strategy 2017, which aims to roll out innovations like the Internet of Things, big data and artificial intelligence across all industries.

Daimler Trucks boss Martin Daum points out that the company two years ago demonstrated with Mercedes-Benz trucks in Europe "that platooning can be done and is highly advantageous.

"Right now, we keep developing the technology with Freightliner on public roads in the US.

"Japan is a key market for us, that's on the lookout and promotes new technologies. We take part in the Japanese government's initiative to push platooning further ahead in Asia and to remain in the lead in the development of this technology."