|Autonomous driving in long-distance truck operations with the “Highway Pilot”. Click to enlarge.|
Mercedes-Benz unveiled the Future Truck 2025 in Magdeburg, Germany. The truck is equipped with the intelligent Highway Pilot assistance system, which enables it to drive completely autonomously at speeds of up to 85 km/h (53 mph). Daimler Trucks demonstrated the vehicle on a trip along a section of the A14 autobahn near the city of Magdeburg, in which the Future Truck drove itself under realistic driving conditions.
The Highway Pilot is comparable to an autopilot system in an airplane—probably the most advanced form of autonomous mobility in existence today, the company noted. Mercedes-Benz will unveil the complete study of the Future Truck 2025 at the International Commercial Vehicle Show (IAA) in September.
The Future Truck 2025 with “Highway Pilot” is based on the Mercedes-Benz Actros 1845. The engine develops 330 kW (449 hp) and a maximum torque of 2,200 N·m (1,623 lb-ft). Power is transferred by the fully automated 12-speed Mercedes PowerShift 3 transmission, which is standard equipment.
Its unusual semitrailer already provides a visual outlook on the near future; Mercedes-Benz presented this Aerodynamics Trailer two years ago, as a world premiere at the International Commercial Vehicle Show (IAA). Aerodynamically optimized, it is able to reduce the fuel consumption of the complete semitrailer combination by up to 5%.
|Sensor system in the Future Truck 2025. Click to enlarge.|
A radar sensor in the lower area of the front end scans the road ahead at long and short range. The front radar sensor has a range of 250 m and scans an 18-degree segment. The short-range sensor has a range of 70 m and scans a 130-degree segment. The radar sensor is the basis for the Proximity Control Assist and Emergency Braking Assist already available today.
The area ahead of the truck is also scanned by a stereo camera located above the dash support behind the windshield. This is currently the location of a mono-camera if the optional Lane Keeping Assist is ordered. The range of the stereo camera is 100 m, and it scans an area of 45 degrees horizontally and 27 degrees vertically.
The stereo camera of the Mercedes-Benz Future Truck 2025 identifies single- and double-lanes, pedestrians, moving and stationary objects, all objects within the monitored area and also the condition of the road surface. The camera recognizes everything that contrasts with the background, and is therefore also able to measure clearances precisely. The front stereo camera also registers the information on traffic signs.
In addition to object and distance recognition, the stereo camera recognizes lane markings as a major function for autonomous track guidance. The road surface to the left and right of the truck is monitored by radar sensors installed in the sides. They are located on the left and right, ahead of the tractor unit's rear axle. The sensors have a range of 60 m and cover an angle of 170 degrees.
Multisensor fusion. The sensors are networked (multisensor fusion), and provide a complete image of the surroundings. All moving and stationary objects in the truck’s vicinity are registered. Fusion of the data from the front radar sensor, side radar sensors and front camera by a high-performance multi-core processor in the central computer provides a continuous view of the entire area in front of and beside the truck. For comparison, the human eye has a 150-degree angle of vision, but its focal area is merely a fraction of this.
The sensor system of the Mercedes-Benz Future Truck 2025 already comes from the next generation of this technology. The sensors can not only recognize the road edge by the marker lines, but even identify the course of the road surface by the roadside features (e.g. guard rails or vegetation).
The sensor and camera technology is active throughout the speed range from standstill to the legally permitted maximum truck speed of 80 km/h. By intervening in the steering, it automatically keeps the truck safely in the centre of its lane. The system also includes a three-dimensional digital map, which is already used for the assistance system Predictive Powertrain Control (PPC). This means that the truck is always fully aware of the road's course and topography.
In addition the digital map and the information from multisensor fusion are used to determine the truck’s own position.
V2V and V2I. The “Highway Pilot” is partnered with V2V (vehicle-to-vehicle) and V2I (vehicle-to-infrastructure) networking. Every vehicle equipped with this in the near future will transmit continuous information to its surroundings, the CAM (Corporate Awareness Message). The vehicle uses this to announce its presence. The information content includes vehicle position and model, dimensions, direction of travel and speed, any acceleration and braking manoeuvres and the bend radii negotiated.
The frequency of information transfer depends on the vehicle speed and the intensity of any changes in its movement. It varies between one message per second when cruising to ten times that interval when changes are significant. Transmission is via WLAN technology, using the standard, Europe-wide G5 frequency of 5.9 gigahertz. The basis is the ITS Vehicle Station (Intelligent Transport Systems and Services) on board the vehicle. Communication between vehicles is also standardized following an agreement between a consortium of automobile manufacturers, suppliers, public organisations and research institutions.
The range of these continuous messages is a radius of around 500 m. The vehicles inform each other about their movements, so that they can respond to them immediately in advance. This includes e.g. reacting to vehicles joining a highway, or when approaching the end of a traffic tailback. Each of these messages certified to prevent misuse. Transmission to this distance also works in unfavorable weather conditions.
If necessary the continuous reports are overlaid with DEN messages (Decentralized Environmental Notification). These give a warning of unusual events, for example emergency braking, activation of the hazard warning system or switching on fog lamps.
V2I means that all these messages and signals are also sent to external recipients such as traffic control centers. These are then able to respond flexibly, for example by changing the speed limit or opening up additional lanes. Messages can also be sent to the vehicles, for example about daytime or temporary roadworks.
If the next relay station for V2I is out of direct range, the information is relayed via other vehicles in the form of a transmission chain. If there is no WLAN network, transmission is by mobile technologies such as UMTS and GPRS.
All these data inform the driver or the onboard computer about events happening outside the range of vision in good time. The driver and vehicle are therefore aware of problems in advance, before they can become a hazard.
Anti-tailback measures: road traffic as a self-learning system. The Mercedes-Benz Future Truck 2025 is therefore not on the road in isolation, but constantly communicates with its environment, unnoticed by the driver. Just as it sends information about its own movements and journey to other vehicles, it receives signals showing the movements of other trucks and any other vehicles. The result is real-time communication between the networked vehicles that cannot be matched by even the most precise radio traffic reports.
In this way information about sluggish and slow-moving traffic is passed between vehicles in advance, also data on tailbacks and their length and duration, or on roadworks—the data are available to all road users. As the networked vehicles respond automatically, a steady traffic flow and efficient use of the limited infrastructure are ensured, better than even the most sophisticated traffic management systems can currently achieve.
In the event of major problems, early information is provided about automatically initiated route changes to the destination or recommended diversions. In combination with autonomous driving, road traffic will develop into a self-learning system.
The average transport speed will be increased by the improved traffic flow alone, without raising the speed limit, and at the same time the smoother flow will save fuel.
Autonomous driving scenarios. The Mercedes-Benz Future Truck 2025 operates independently of other road users thanks to networking, not by being daisy-chained with a lead vehicle.
If there is another vehicle traveling ahead, the truck automatically adapts to its speed within the permitted limit and maintains a set safety distance. It is therefore always possible for other vehicles, e.g. a car cutting in ahead when moving from the overtaking lane before an exit, to do so safely. Here too the safety distance is always maintained—the Future Truck 2025 adapts to its environment.
As soon as the “Highway Pilot” system has been activated, the driver is able to pivot the driver’s seat to the co-driver’s side by 45 degrees, into a working or resting position. In the cockpit of the future, which has a completely newly designed center console in the style of an office workstation, the driver is now able to use a removable tablet computer with a touchscreen for other activities such as communicating with the outside world. The new cockpit also gives the driver considerably more freedom of movement.
Before departure, the schedulers would have used telematic systems to transmit the current transport assignment to the vehicle, where it is shown to the driver on the integrated display. The destination address is sent to the navigation application in the data cloud. The navigation computer calculates the most efficient route using real-time information from the networked vehicles on the road.
Networking between vehicles ensures that both the truck with its host computer and the driver are always informed about the route ahead. The same applies to any major events behind the truck—for example an approaching emergency vehicle where traffic is tailed back. The truck’s control system is able to respond to such events and leave the traffic lane for a brief period. While on the move, the driver always has further information such as remaining driving time, range or preferred service areas along the route available.
In the Future Truck 2025 too, it must always remain possible for the driver to resume manual control. Two cameras therefore monitor the cockpit and a sensor the driver’s seat.
Autonomous overtaking maneuvers are not envisaged, they must be performed by the driver. The same applies to leaving the highway or changing lanes where the road forks.
Before deactivation of the “Highway Pilot”, the driver is given advance visual notification followed by an audible warning to resume manual control of the truck. This could become necessary if the situation changes and requires increased vigilance or resumption of control owing to e.g. roadworks or obstacles on the road. Autonomous driving is a “can” function – the driver can always decide freely whether to take personal control or leave things to the technology.
The driver is notified in good time when approaching the relevant exit road. The driver returns the driver’s seat to the driving position and assumes direct control of the truck, like the pilot of an aircraft before landing.
Background. The world premiere featured a demonstration of the truck’s technology in the presence of several hundred media representatives, government officials, businesspeople, capital-market analysts and investors. In addition, Daimler AG held a conference on the future of freight transport. The goal of the event was to establish an ongoing dialogue with all stakeholders about the conditions for transport in the future, in which self-driving trucks will play a major role.
If the legislative framework for autonomous driving can be created quickly, the launch of the Highway Pilot is conceivable by the middle of the next decade. That’s why Daimler Trucks is committed to maintain a dialogue with government officials and authorities, and with all other parties affected by this development. We believe the chances of success are good, because autonomous driving combines the ability to achieve business and technology objectives with the creation of benefits for society and the environment.—Dr. Wolfgang Bernhard, the member of Daimler’s Board of Management responsible for Daimler Trucks and Buses
The “World Transport Reports” study conducted by the ProgTrans consulting company predicts that freight transport volumes in the EU will increase by approximately 20% between 2008 and 2025. There will be virtually no change in the shares of that volume accounted for by different transport modes. This means that trucks will continue to account for around 75% of all freight transported by road in the EU.
The volume of road transport in Germany alone will increase from 3.7 billion tons today to nearly 5.5 billion tons by 2050, according to the country’s Ministry of Transport and Digital Infrastructure. Reducing the cost of such shipments would spur economic growth.
This boost would be welcome, especially because competitive and cost pressures are growing in the freight-forwarding sector. Rising fuel prices, road tolls and more stringent environmental regulations are making the purchase and operation of trucks more expensive, and it is also becoming increasingly difficult to find well-qualified truck drivers.
Mercedes-Benz is already an industry leader for driver assistance technology in trucks, having installed hundreds of thousands of proximity cruise control, automatic braking, stability control and lane-keeping assistance systems.
Another new system known as “Predictive Powertrain Control” uses information about road topography and route characteristics to adjust the operation of the drivetrain in order to maximize fuel economy.
Additional and improved assistance systems will follow in the coming years. These systems will communicate with one another and enable vehicles to operate without any driver intervention, especially on highways and major roads.
Optimally executed acceleration and braking phases will help to ensure a homogeneous flow of traffic and will reduce fuel consumption and emissions of the Future Truck 2025. Autonomous driving will also enable more precise transport scheduling. Moreover, trucks that communicate with each other can travel more closely together and therefore take up less road space. There would be fewer traffic jams and the associated costs would be reduced. Finally, the lower risk of accidents caused by human error would reduce insurance rates.
The Highway Pilot system will significantly upgrade the job profile of truck drivers, Mercedes-Benz suggests. It will not only free them from having to perform monotonous tasks; it will also give them more time for tasks that were previously handled by office workers at shipping companies. In other words, it will be possible for truckers to advance to new positions as transport managers, making truck driving a more attractive profession. Autonomous driving could thus help to resolve the shortage of truck drivers.
Along with numerous new components, the Future Truck 2025 also includes systems that are already in use, in passenger cars for example. In this regard, Daimler has once again demonstrated its ability to transfer technology within the Group.