IN PRINT — Tailgate Party: Platooning questions involve more than tech
Posted: June 27, 2017 by Eric Berard
Nike wants a runner to complete a marathon in under two hours, but the target will involve more than the company’s swoosh-marked shoes. Other marathoners will take turns running in the controlled race, helping to optimize the aerodynamic conditions that can be leveraged by the record hopeful who will tuck in behind them.
It’s not the only sport to leverage the pulling forces of “drafting”. The concept has been used everywhere from cycling’s Tour de France to the ovals of NASCAR. With the help of emerging technology such as adaptive cruise control and collision mitigation systems, trucking could be on the cusp of realizing the same techniques – using automatically set following distances in a process known as platooning.
“At 65 miles per hour [105 kilometers per hour] and a 30-meter gap separation, the fuel savings for the second and third trucks in the queue are in the ballpark of 6% and 10%, respectively. Additional aerodynamic enhancements to the tractor would, of course, further improve the fuel efficiency,” says Aravind Kailas, senior engineer with Volvo Group’s Advanced Technology and Research Division. Those numbers have been proven during demonstrations in California. A test of European models saw gains between 10-15%.
The numbers are echoed by manufacturers and regulators alike. Preliminary findings from Transport Canada – presented during a December meeting of the Canadian Council of Ministers of Transportation and Highway Safety – suggest 6% fuel savings for platoons of three tractor-trailers, when each vehicle weighs 65,000 pounds, is spaced 17.4 meters or 0.6 seconds from its leader, and the trailers don’t have any aerodynamic devices such as side skirts or boat tails. Tests with aerodynamic trailers, conducted at a track in Blainville, Quebec, realized fuel savings of 14.2%.
“There are a lot of factors and variables that will influence the actual savings. Things like following distance, vehicle speed, aerodynamic shape of the trucks in the platoon, available platooning miles, and so on,” cautions Stephan Olsen, Kenworth’s director – product planning.
The variables don’t end there, either.
“Topography, weight of the vehicles in the platoon, powertrain performance and the time that trucks are in platoon mode will definitely have an impact,” adds Hayder Wokil, autonomous and automated driving director at Volvo Trucks.
Tight following distances could actually cause some conditions known to harm fuel economy.
“If you’re collapsing that following distance, then are you impeding some of the airflow that’s going to the cooling system, and you are overworking some of the engine’s cooling systems. The cooling fan could be engaged all the time, creating parasitic load,” explains Scott Perry, Chief Technology and Procurement Officer with Ryder System.
Navistar’s Darren Gosbee, vice president – powertrain and advanced technologies, agrees: “There’s an optimal point where you need to balance the airflow through the radiator in order to minimize the fan time and also a distance to maximize the drafting benefit.”
Setting aside the strain on the cooling package, there are other potential maintenance gains to be realized downstream. Gosbee refers to longer tire life because of the drop in “tractive effort”. Volvo’s Wokil talks about the optimized performance realized through automation.
Perry is less optimistic. “I do not believe in [the maintenance gains]. The benefit comes from the fuel economy,” he says. “If there’s less fuel consumed by a vehicle, I agree there could be less oil dilution and oil consumption, and it could … translate at some point in the future by a differentiated service interval.”
Technology-related issues are not the only factors to be addressed. The ideal following distances represent a legislative hurdle of their own. Ontario, for example, currently mandates 60-meter gaps at speeds above 60 kilometers per hour, except when overtaking and passing.
Outside of the potential for better fuel economy, productivity could be improved if drivers of platooning vehicles are in the position to perform other duties. But any significant gains here could require a legislative change to Hours of Service. Is the person in the driver’s seat of a platooning truck recording their status as On-Duty: Driving, or On-Duty: Not Driving, such as when they perform a circle check? How would enforcement teams view the Hours of Service if the truck is essentially accelerating, braking, changing gears, and steering on its own?
“If he or she is steering, then I would consider it as On-Duty: Driving,” said Darin Wheaton, an enforcement officer with Nova Scotia’s Department of Transportation and Infrastructure Renewal.
“In regards to semi-autonomous trucks, under the current regulations the driver is considered as driving, so the rules remain the same,” agrees Eric Santerre, a spokesman for Controle Routier Quebec. “Considering the Quebec particularities [roadways, weather, etc.], the introduction of such vehicles in Quebec is certainly not going to happen any time soon.”
Federal regulators have not unveiled any plans for different Hours of Service rules for platooning drivers, either, but Transport Canada has said in a recent report that platooning could reduce driver stress and workload. If it’s truly less tiring, what does that mean in terms of future logbooks?
Angela Splinter, Chief Executive Officer of Trucking HR Canada, still emphasizes that employees will need to play a role in any fleet’s decision to adopting emerging technologies like platooning vehicles. Human Resources teams can ensure training aligns with the demands for different skills.
“Don’t forget about your dispatchers and safety personnel and how their role may be changing, too,” she adds. “Any organizational change needs to be effectively managed, and your HR person can help you do that.”
The required technology may not even be limited to the way the truck performs. Perry believes platooning will need to be offered with some form of commercial trading platform to distribute the wealth when more than one fleet is involved. Vehicles to the rear, for example, realize greater percentages of fuel economy gains. Their drivers are certainly the ones that have the greatest opportunity to focus on other duties from the driver’s seat.
“If you’re gonna follow me, I want some of that benefit. So I can see an entire ecosystem between fleets to share all those benefits, maybe through a credit system,” says Perry.
The same platform could be used to evaluate and choose the carriers you are willing to platoon with, especially when it comes to safety records, he says. “Just because they have the IT system installed on their truck doesn’t mean that they’ve done adequate service on it. If they don’t have a good maintenance history and record, I don’t want them platooning behind me because their ability to stop at the same time I’m able to stop may be very different.”
Navistar’s Gosbee says that truck weights also need to be considered, since the lighter trucks could potentially reach higher speeds or more easily maintain gear choices than their heavier counterparts in the platoon. Maybe they would need to be compensated for the longer trip times.
There is time to work out answers to such questions, of course. The European Automobile Manufacturers Association recently suggested semi-autonomous truck platoons could be a reality by 2025.
“It’s probably less than 10 years from now,” Gosbee says. “Because the fuel economy benefit is so high, the industry would be foolish not to figure it out.”
The idea of drafting is not yet legal for trucks. Provinces still set minimum following distances that are larger than the gaps suggested for technology- governed platoons. But the technique already has a home on race tracks.
Patrick Carpentier, a Canadian race car driver who made his mark on Formula Atlantic, IRL, Champ Car and NASCAR circuits, credits some of his success to drafting techniques, and offered his observations about how it works.
“There are different aspects to performance in racing, but drafting is definitely one of them. The higher the speed, the more vehicles aligned in a platoon, and the stronger the head wind, the more effective drafting becomes” he says. “Even a really tiny difference makes a huge [difference] at the end of the race.”
The trailing car is essentially being pulled by the car in front, he explains. “You don’t have to break the wind upfront. Then you just coast a lot longer and that’s where you save a lot of energy.”
Still, he wonders if the underlying technology for truck platoons could lead potential drivers to look at other careers.
“The downside of all these new technologies, like cars or trucks that drive themselves, is that it can get very boring,” Carpentier says. “If what makes your life becomes the back of another truck, I’m not sure there’ll be as many drivers available.”
– Carpentier is a spokesman for the Formula E race in Montreal, July 29-30.