Daimler Trucks has shifted gears in its ongoing effort to develop autonomous vehicles. By fitting its Highway Pilot self-driving system to a Mercedes-Benz Actros truck and steering it down a stretch of Autobahn 8 near Stuttgart, the company has marked the first time an autonomous production semi has been tested out on public roads.
Much like the posited advantages of self-driving cars, Daimler says improvements in driver safety are a compelling reason to pursue the technology in the road freight sector. By allowing autonomous systems to shoulder some of the burden on long-haul journeys, it says it can reduce driver fatigue and limit mistakes and distractions. Furthermore, when it comes to changing gears, accelerating and braking, the system is said to be more efficient, meaning less fuel and carbon emissions as a result.
Daimler's Highway Pilot system first debuted on the open road last year aboard the Mercedes-Benz Future Truck 2025 – a concept vehicle intended to demonstrate what a future of autonomous trucking might look like. Then earlier this year another of the company's concept vehicles, the Freightliner Inspiration, received official licensing to roam the public highways in the state of Nevada.
The latest autonomous expedition saw the Highway Pilot system installed and tested in something other than a concept vehicle for the first time. Onboard the modified Mercedes-Benz Actros was Daimler executive Dr Wolfgang Bernhard and Winfried Kretschmann, Minister-President of the state of Baden-Württemberg, who travelled along the Autobahn 8 between Denkendorf and Stuttgart with the Highway Pilot system helping guide the way.
The system uses a short-range radar that assess the vehicle's surroundings up to 230 ft (70 m) away in a forward-facing 130-degree arc, while a long-range unit scans out to 820 ft (250 m) in an 18-degree arc. These work in conjunction with Active Cruise Control and Active Brake Assist, along with a stereo camera that identifies road markings and guides steering.
While self-driving is the name of the game, Highway Pilot isn't about letting those behind the wheel plonk their feet on the dashboard and snooze their way to their destination. Daimler likens the system to the autopilot used in aviation, in that the driver must be prepared to take control at any time. The system can prompt the driver to do so if there is a change in weather or road conditions, and if they don't respond in time the truck is brought to a stop.
To conduct this demonstration, Daimler had to obtain a special permit from Germany's road traffic regulator, allowing the truck to be driven semi-autonomously on highways at speeds of up to 80 km/h (50 mph).
While widespread adoption of autonomous trucks still appears some way off, the opportunity to test out the technology in real-world scenarios will help speed up the process.
"Safe testing in real traffic is absolutely decisive for the development of this technology to market maturity," says Bernhard. "We are now able to proceed with this."