Snow removal on airfields: Automated Mercedes-Benz Arocs trucks clear the way

Daimler Press Release:

• Self-driving snow removal vehicles in test operations with Fraport
• Premiere of the latest Mercedes-Benz "Remote Truck Interface" technology
• Real-time data sharing among all vehicles
• Airfield clearance requires high-precision driving: the Arocs makes it possible
• Proven series-production technology is the basis for advanced innovative solutions

Stuttgart / Bad Sobernheim – In an unprecedented test, Daimler AG is demonstrating another potential solution for the future use of automated commercial vehicles. Following the successful demonstration of the innovative Highway Pilot and Highway Pilot Connect systems, the latter making truck platooning possible, the company today presents another development step forward on the road to the fully connected and autonomous commercial vehicle.
On the site of the former Pferdsfeld airbase, the world's leading manufacturer of commercial vehicles demonstrates the practical application of automated snow removal operations at airports based on a specific customer requirement.

Martin Daum, the Daimler AG Board of Management member responsible for Daimler Trucks, emphasises: "We are not just talking about new technologies, we are bringing them onto the road. Step by step we are developing our very latest assistance systems even further – with a view to automated driving. We are currently working on the implementation of two specific use cases: Firstly automated driving in quite normal traffic on motorways – with the clear aim of relieving driver workload and significantly improving safety. And secondly driverless operation in enclosed areas to significantly improve productivity. With today's demonstration of automated snow clearance on an airfield, we are once more reinforcing our claim to technological leadership."

Under the project name "Automated Airfield Ground Maintenance“ (AAGM), four Mercedes-Benz Arocs tractor units demonstrate automated airfield clearing in a remote-controlled convoy. The benefits are obvious: Airfield clearances are hard to predict and thus difficult to plan, especially in winter. This makes snow removal units operated with pinpoint precision by a single vehicle operator to remove snow from runways especially crucial when extreme weather strikes without warning during the winter months, and they require no additional vehicle and staff scheduling.

The project was established in close cooperation between Lab1886, the Daimler innovation incubator, Daimler Trucks and Fraport AG. Lab1886 actively supports the transformation of Daimler AG from an automotive manufacturer to a mobility provider, and works closely with the Daimler CASE initiative. CASE – � these letters shape the future of mobility and are an integral part of the corporate strategy of Daimler. They stand for the fields of connectivity (Connected), autonomous driving (Autonomous), flexible use (Shared & Services) and electric powertrains (Electric).
"The mission of Lab1886 is to develop new innovative business models for Daimler. The Fraport project is a great example in this regard. It shows how we bring together innovations with specific customer needs to develop new markets“, says Susanne Hahn, Head of Lab1886.
"As one of the first airports worldwide, we are pleased to be contributing our know-how to this innovative project. It enables us to examine autonomous control of heavy winter service equipment in the especially challenging winter conditions of an airport. We hope to obtain findings that will help us to plan the future deployment of equipment even more precisely and efficiently under sudden wintry conditions. Our commitment once again underlines the role of Fraport AG as an innovation driver in a wide range of areas," says Mathias Dudek, head of Infrastructural Facility Management at Fraport AG.

Based in Frankfurt/Main, Fraport AG operates one of the world's largest air traffic hubs. The objective of the joint testing activities is the implementation of state-of-the-art telematics-based vehicle control technology in areas not accessible to the public. This is one of the key aspects in which the new application differs from the technology milestones in the area of autonomous driving developed and realized for practical testing by Daimler to date. The Highway Pilot and the Highway Pilot Connect system presented for platooning are designed for use on public roads.
In addition to a comprehensive set of requirements on automated operating machines, Fraport also supplies the snow removal equipment for this unparalleled test. Among the equipment are four so-called sweeper blowers of the kind already in operation today as semitrailers towed by still conventional Mercedes-Benz tractor units.

Premiere for the "Remote Truck Interface" (RTI)
The four Arocs test vehicles are equipped with the new Remote Truck Interface (RTI) for remotely controlling vehicle functions and exchanging data. The RTI is the centrepiece of the new technology, for which Daimler can draw on a significant pool of knowledge and engineering from projects such as the advanced Highway Pilot and Highway Pilot Connect systems.

All vehicles are fully interlinked via the RTI by means of telematic systems, all operate automated and all are able to lead or follow in the vehicle convoy. Specifically, this means that a convoy leader chooses a random unit from a fleet of available semitrailer combinations and defines this as the "lead truck". He then uses a control panel to define the number and sequence of the other convoy vehicles, and conducts a pre-operation inspection of his and all other semitrailer combinations.
What sounds simple is actually just as simple in practice. However, the complexity of the software behind it is enormous. All vehicles are equipped with dual GPS tracking (DGPS) and of course state-of-the-art vehicle-to-vehicle communication (V2V communication) technology.

In addition, the interplay of the innovative RTI and the remote control unit provides extremely fast and not least secure date exchange among vehicles. To make this work in real time, a full data exchange between the vehicles and the main control unit of the RTI takes place every 0.1 seconds. The transmissions in the area of V2V communication are based on the "Digital Short Range Communication DSRC“ technology.

Looking ahead: automated driving offers a wide range of possible applications
The automated snow removal convoy comprises four vehicles during the test phase and can be expanded to up to 14 units. It paves the way for further applications. In addition to other airports that have already signalled interest in such precision work machines for automated runway maintenance, solutions for a wide variety of applications are feasible thanks to the Mercedes-Benz Remote Truck Interface.

"This opens up new possibilities for our customers: High-precision manoeuvring procedures of conventional trucks, remotely controlled by the driver outside the cab – for example, positioned at the rear of the vehicle with a perfect view of the manoeuvres – are possible, as is unmanned driving in mines, at container terminals or other closed-off sites", says Martin Zeilinger, Head of Advanced Engineering at Daimler Trucks.

The tasks of the automated Arocs in AAGM (Automated Airfield Ground Maintenance) test operations
In the case of the demonstration of the Arocs tractor units, the Remote Truck Interface connects the vehicle with the outside world. The control functions for track guidance and operation of the convoy are housed in additional external control units such as the track computer, the operating panel and the wireless interface. Specifically this means that the automated Arocs trucks are able to perform the following functions:

• Control: engine start/stop
• Control: parking brake
• Vehicle lateral control: steering
• Vehicle longitudinal control: engine control (throttling up and down)
• Vehicle longitudinal control: service brake
• Powertrain management: transmission (engage start-off gear, all gear changes, engage neutral)
• Powertrain management: activation and deactivation of the differential locks
• Peripherals: lights including turn indicators, rotating beacons and much more
• Special functions: body control; here: control of the mounted sweeper blower

The RTI control unit allows actuation of all connected vehicle functions via an interface (CAN). Remote control is thus possible by integrating a wireless interface into the CAN.

"An important component of the RTI control unit is the integrated safety concept. This means that all vehicle functions are monitored. The safety routine is executed as soon as an error occurs. In this way we can ensure that the vehicles can be stopped safely and quickly if needed, and can then simply be operated manually", Zeilinger adds.

The test operations: snow removal equipment must offer highly flexible responses
In the past, airport operators have had to keep the required removal and cleaning equipment in an operational stand-by condition. The lead times for relatively rare and usually short-lived bad weather periods tie up major capacities.

On the other hand, an airfield requires consistent and thorough clearing operations even when just a little bit of snow covers the ground. On such sites, the snow must be cleared to one side over a width of up to 60 metres in a single pass. In the case of Frankfurt Airport today, up to 14 vehicles drive in a convoy with the appropriate overlap.

This means the snow is "passed on" from the front to the rear from one vehicle to the next. As a result, the snow load increases from vehicle to vehicle, and the performance requirement for the individual snow removal units rises sharply from front to rear. Furthermore, the staggered driving also makes high-precision guidance crucial for the quality of the clearing pattern. All this necessitates highly dissimilar requirements on the performance of each snow removal vehicle.

Efficient operations thanks to automated snow removal machines
In the case of Frankfurt-Main airport, the convoy must keep the runways and taxiways free from snow and ice as a precisely staggered formation. To date, snow clearance machines have worked their way along metre by metre under poor visibility conditions in darkness and fog, with snow constantly being thrown up by the vehicles driving ahead.

The poor visibility often leads to increasing distances between vehicles, opening up the convoy and extending the time it takes to clear a runway. Moreover, poor visibility can lead to the outer vehicles damaging the runway marker lights, which are very expensive to repair.

In the test of the autonomously operating snow removal trucks of Daimler, a predefined snow removal programme – under the constant control of a convoy leader – specifies the routes, direction and speed. The person in the lead vehicle of the removal convoy in charge of the demanding task enjoys relatively good visibility of the swaths to be cleared ahead of the lead and the trailing vehicles.
The swaths to be cleared are predefined with the goal of a high-precision clearing trajectory. This means the routes to be driven are always specified cartographically and are followed with pinpoint precision thanks to a differential GPS system – accuracy: three centimetres – by the lead vehicle as well as the other convoy vehicles thanks to constant target/actual comparisons.

A high level of flexibility is also a must for snow clearance operations on airfields. That is why the convoy leader – owing to suddenly identified and then immediately required deviations from the digitally specified clearing path – is able to take over the routing personally at any time.
To this end, the convoy leader has the classic controls - steering wheel, accelerator and brake pedal - at his disposal in each Arocs – and thereby full control over the vehicle. The trailing vehicles then immediately and fully automatically adopt the target paths resulting for them from the change of the route of "vehicle 1".

All-wheel drive Arocs 2045 AS 4x4 as the basis for the snow-clearing semitrailer combination
The prototype convoy from Advance Engineering presented now comprises four individual vehicles initially. The basis is provided by all-wheel-drive Mercedes-Benz Arocs 2045 AS production tractor units from the robust Grounder product range, equipped with the latest OM 470 LA engine generation certified to Euro VI standards with an output of 315 kW (428 hp) and producing 2100 Nm of torque. At a brisk speed, most of the mass of snow is thrown to the side by a fully hydraulic, three-section snow plough measuring eight metres in width.

The finishing surface clearing touches are carried out by a sweeper, a so-called sweeper blower. It is towed as a semitrailer and powered independently of the tractor unit by a six-cylinder engine from Mercedes-Benz installed at the rear of the semitrailer.

The entire tractor/semi-trailer combination is 23 metres long and weighs 25 tonnes in operational condition. The tractor unit, which was reinforced in the area of the snow plough mounts, accounts for about ten tonnes, the plough blade adds two tonnes to the total weight, the semi-trailer with the sweeper blower has a gross weight of 13 tonnes.

Innovation as a tradition: Daimler Trucks is the leader on the road to autonomous driving
Mercedes-Benz has traditionally taken the lead in new safety and assistance systems, and in improving the driver-friendliness of commercial vehicles. The same applies to networking and automated driving. Know-how accumulated over decades is the basis for developments such as the Highway Pilot and Highway Pilot Connect, on the road to automated driving.

The Future Truck 2025 presented in 2014 with the Highway Pilot system was the answer to the challenges of the future: increasing traffic, inadequate infrastructure, growing cost pressure and shortage of drivers. Based on the current Mercedes-Benz Actros and its numerous, improved assistance and telematic systems, it ushered in a new era for road goods transport.
Only one year later, the Freightliner Inspiration Truck continued to write history. Its technology is based on the Future Truck 2025, but adapted to suit North American operating conditions. The Freightliner Inspiration Truck was the world's first automated driving truck to have operating approval for the public roads of Nevada.

Shortly afterwards, Daimler Trucks opened up a new chapter in Europe: in autumn 2015, a standard Mercedes-Benz Actros with the Highway Pilot was given approval for public roads as a test vehicle. It is permitted to drive on all German autobahns in semi-automated mode. This means that the vehicle drives automated, but the driver must constantly monitor the system and be able to take over control at any time.

While the Mercedes-Benz Future Truck 2025 was a concept vehicle, the transition to series production technology has proved successful in the form of the Mercedes-Benz Actros with the Highway Pilot. It demonstrates the everyday suitability of automated driving.

As early as 2016, three Actros trucks with the Highway Pilot Connect took to the roads: the technology allows electronic docking by vehicles on motorways and long-distance highways, also known as "platooning". During the cross-border European Truck Platooning Challenge, Daimler Trucks was able to demonstrate the advantages of electronic vehicle-to-vehicle networking on the journey to Rotterdam. In truck platooning, connectivity and automated driving increase safety for trucks driving in convoy, relieve driver workload and improve fuel efficiency by reducing distances between vehicles.