Trucks can save on fuel by driving in close convoy. Commercial vehicle manufacturers are pouring effort into the digital technology of truck platooning. But it will not be enough just to get the technology to function. For platooning to make good business sense, the haulage industry will have to rethink how it operates.
Few motorists would have given a second glance to the two trucks on the Nuremberg-to-Munich highway. Yet not all was as it seemed with the white HGVs making unhurried progress south in close convoy. In fact, the second truck’s driver could theoretically have taken both hands right off the steering wheel. His truck was being autopiloted in a convoy, or “truck platoon”, as part of a test conducted in late 2018 by the Schenker logistics group with truck manufacturer MAN.
The trial showed that platooning can indeed work in practice, out on real roads. But is it really worth it? Some experts predict a great future for convoy driving: it
cuts emissions and costs, and takes the strain off drivers. Others see it as a dead-end technology, maintaining that the benefit fails to outweigh the costs. Various scenarios are conceivable, with trials and studies underway worldwide. As every Tour de France cyclist knows, drafting – or staying in the slipstream of the bike in front – saves energy. And trucks are no different. When these insights are modeled in numbers, the potential of the technology becomes evident. By closing to within 15 meters of the truck in front, as opposed to 50 meters, a truck can save up to 10 percent on fuel costs. The impact on resource savings would be huge. According to the International Energy Agency, the global truck fleet consumes 17 million barrels of oil every day. With truck platooning, 1.7 million fewer barrels of oil would have to be produced, equivalent to around 4,660 tank trucks per day.
The environment is technologically challenging.
The purpose of the Schenker and MAN road trials was to test the validity of these calculations. Two standard-issue trucks, equipped with additional technology and sensors, were sent out several times daily to determine whether the machines (and drivers) would work in a platoon. The team is still busy evaluating the data from 35,000 test kilometers, but basically the verdict is positive. “The technology worked smoothly,” says Dr. Chung Anh Tran, the project lead at Schenker.
Radar, Lidar and WiFi ensure security
The potential is also being explored by auto industry suppliers. Continental, for example, plans to unveil a demonstrator this month, a complete technical package co-developed with Knorr Bremse to make trucks ready for platooning. “This is a technologically challenging environment,” says Jörg Lützner, Head of Portfolio & Innovation Management for Commercial Vehicles at the Continental Interior Division. The challenge lies mainly in the strict safety requirements. Ideally, the trucks in the convoy are less than one second apart at highway speed, a distance that would be unsafe for a sole driver. If the pilot truck brakes, all the following trucks must react instantly. Environmental sensors such as radar or lidar (laser distance measurement), a permanent WiFi-based radio link and redundant systems ensure everything works reliably – even in the unpredictability of real traffic, where thoughtless drivers can potentially force themselves between the trucks. If this happens, the system increases the distance until the driver can resume control. As Jörg Lützner explains, the technology is in principle available. It now needs to be refined in road trials.
Intelligent truck platooning in the cockpit (Image: MAN)
The breakthrough for platooning will hinge on manufacturers reaching consensus on a system. Otherwise, a convoy could only comprise one brand of truck, and much potential would go to waste. The industry is aware of the mono-brand issue, and has joined forces in the EU platooning initiative “Ensemble”. The project brings together truck manufacturers from DAF to Volvo, and suppliers from Bosch to ZF. Their shared goal is to advance multi-brand platooning, and to be staging trials on European roads within the next three years. If this succeeds, experts expect platooning to gain rapid traction. “We assume truck platooning will be established on long-distance roads by the 2030s at the latest,” estimates Dr. Chung Anh Tran of Schenker. Some experts are even predicting 2025 as the breakthrough year.
Costs are high – but does the technology also deliver?
It is not yet clear who will earn money from truck platooning. Will truck manufacturers take charge of developing the advanced technologies such as lidar themselves? Or will they leave it to suppliers? Daimler has found its own answer to this strategic question, and in the next few years plans to invest 500 million euros in automated truck technology. Scania is also going with its own system. Suppliers such as Conti, on the other hand, hope other manufacturers will prefer to outsource the complex and sensitive issue of semi-automatic driving. Which will prevail – make or buy? Time will tell.
Every time the platoon separates, it eats into the savings.
Either way, it will be the haulage contractors who pay. Experts estimate that a platooning-ready, self-driving truck will cost around 23,000 euros extra. Assuming the vehicle puts in 100,000 kilometers per year at a fuel consumption of 30 liters per 100 km, the freight forwarder would save 2,922 euros per year on diesel (based on today’s fuel prices) thanks to platooning. The additional outlay would thus be recouped after about eight years.
Vehicle communication at MAN truck platooning (Image: MAN)
But there is one major question overshadowing the entire landscape: how much diesel can really be saved by staying in the slipstream of the vehicle in front? Can contractors really expect double-digit percentage savings, as the simulations predict? Schenker and MAN are waiting for the trial data to be evaluated before making an official pronouncement, but sound generally optimistic. The same goes for Continental. “We are confident that distances of under one second are achievable. This should make it possible to realize the savings,” says Jörg Lützner.
Discipline is paramount
Theoretically, everything points to a great start for the technology. If it weren’t for Daimler. In a surprising move just before the end of 2018, the company
pulled the plug. According to one manager, platooning tests in the USA showed that “even in ideal conditions the savings fall short of expectations”, and that there is no business case for the technology on long-haul routes, not even on the laser-straight, empty overland highways in the USA. This announcement surprised many and fomented doubt. If the European truck market leader is giving up on platooning, this supposed “technology of the future” might not have a future at all.
Confidence in the technology has at least taken a hit. Daimler has deliberately laid its finger in the wound: the benefits of platooning hinge on very many “ifs”. Convoy driving saves fuel above all when trucks can roll along the highway in an uninterrupted flow, like trains. “Every time the platoon separates, it eats into the savings,” explains Sebastian Völl, Project Manager for Automated Driving at MAN Truck & Bus, Munich. If a following vehicle is forced to brake for any reason – say a car shoehorns its way into the convoy – the chain breaks. The drivers then have to brake and accelerate manually to get the trucks back into convoy. This costs fuel. And there are likely to be many maneuvers of this nature, especially on crowded European highways. Factor in the many access ramps and junctions where vehicles have to reduce speed, and the result is anathema for perfect truck platooning. That is why manufacturers are cautious in their plans. “In Central Europe we favor two-truck platoons,” says Völl. “In Scandinavia three or four vehicles would also be conceivable.”
Platooning requires a trustworthy mediator.
Another curb on progress could be legislation. MAN and Schenker needed a special permit to have their trucks drive 15 meters apart during the tests; 50 meters is the mandatory distance. This law, like many others, would have to be changed. Above all, liability issues still need to be clarified. What would happen if the pilot truck caused an accident – or is caught speeding? It all spells work for national and regional Ministries of Transport, not exactly known for overly fast action.
Will all actors trust each other?
But the biggest hurdle for truck platooning could be the users, the haulage companies. Because to unlock the advantages of the technology, they will have to rethink how they do business. Platooning is not something each haulage company can do on its own. It only makes sense if vehicles of multiple haulage companies and logistics groups can team up quickly and easily. This would take a platform that players could use to form convoys at short notice.
The Dutch IT company Ortec, for instance, has already developed a platoon matching program that identifies and suggests platooning opportunities. However, using a “drafting exchange” like this is not without problems for freight forwarders, as they would have to disclose information that would be of interest to competitors: routes and departure times. “This is why spontaneous platooning requires a trustworthy intermediary, and all data has to be anonymized,” confirms Continental expert Lützner.
The digital hub would also have to ensure that savings were shared equally, creating an incentive for everyone to participate. The trucks in the slipstream do after all benefit at the expense of the vehicle in front, and the company operating this truck would expect its fair share of the savings. But who would operate the platooning hub? And would players in the transportation industry, where there is a hard fight for the slimmest profits, really make common cause? As happens so often with
digital transformation processes, the sticking point is not the hardware. It’s the biological software: humans. The future of truck platooning will not depend on radio standards; the real make-or-break issue is trust between forwarders.
Supplier Continental also wants to save with truck platooning (Photo: Continental)
Interestingly, commercial vehicle manufacturers and suppliers took Daimler’s withdrawal calmly. One reason might be that Daimler is still contributing to initiatives such as Ensemble, and is continuing to invest in automated truck-driving technology. But the key factor is more likely that commercial vehicle manufacturers have a Plan B. They know the development is not in vain, even if truck convoys fail to materialize. “We see platooning as an important step towards autonomous driving,” explains Schenker manager Tran.
In fact, all trucks that automatically follow a leader are already semi-autonomous. Drivers do not have to navigate the traffic themselves, overtake or change lanes; they can however steer independently and have control of the accelerator and brakes. The manufacturers are currently perfecting the underlying systems. Today the systems are in platooning prototypes; tomorrow they could be in a completely autonomous robotic truck. They commercial vehicle industry is already moving in convoy into the future – with or without platooning.