Platooning is one of the steps toward autonomous trucking, but still requires drivers in all trucks, NACFE says.

Platooning is one of the steps toward autonomous trucking, but still requires drivers in all trucks, NACFE says. 

Platooning – the electronic linking of trucks where a lead vehicle largely controls the one following -- would save about 4% in fuel compared to a pair of rigs running separately, says the latest “confidence” report from the North American Council on Freight Efficiency.

The money thus saved will pay back an investment for necessary equipment in one to two years, say estimates in “Two-Truck Platooning,” released Wednesday by NACFE. 

"Two-truck platooning is showing real promise as a fuel-saving technology, even when considering the actual performance in real-world use,” said Mike Roeth, the organization’s executive director, in a statement.

Fuel savings come from reduced air turbulence between the two tractor-trailers when they operate 40 to 50 feet apart, Roeth said. Reducing that distance should save more fuel, but would introduce operating complications, like reduced air flow to the second truck’s radiator.

Testing shows that reduction in fuel use is 7% as the vehicles move at highway speeds, he explained. But probably one-quarter of the time they would not be operating as a platoon as they split up to pick up and deliver freight, stop for driver rest breaks, etc., during a trip. Taking out those times yields the 4% figure.  

Payback estimates outlined in three scenarios set equipment costs at $1,050 and $2,800, with the higher figure including more equipment than the lower dollar amount. Installation cost of $200 was also factored in.

Equipment includes collision avoidance systems, adaptive cruise control, and in-cab cameras – all now available on the market, Roeth said. Vehicle-to-vehicle radios, the key element, are not yet available but should be soon as testing and perfecting progress.

Two scenarios assume a tractor would platoon three-quarters of its running time, and a third scenario assumes it would do so half the time. Fuel was pegged at $3 per gallon, which it might be by the time platooning comes into common use.

Two trucks now comprise a platoon in most testing here and in Europe, said Roeth and two researchers: Jack Roberts, a freelance truck writer and HDT contributing editor, and Rick Mihelic, an industry consultant and former engineer at Peterbilt Motors.  

More than two trucks could platoon, explained Roberts, with the number limited by the range of the radio signal that links the vehicles. “Daimler,” which is testing in Germany, “puts that at 200 meters,” he said. “That brings it to 10 trucks.”

Education campaigns will be needed to alert the public to platooning and what trucks engaged in it will look and act like, Roberts said. Law enforcement officers, too, need to be informed because even the 40- to 50-foot interval is close by currently held safety standards, Roeth added.

Stopping distances are not a problem because the brakes of the following vehicle would apply so quickly, in 1 millisecond after the lead driver applies them, Mihelic said. Meanwhile, protocols for which vehicle leads and which follows need to be worked out. 

Two-Truck Platooning is NACFE’s 14th project,  Roeth said, and it was conducted using a standard method.

“We used our common approach as we’ve done in previous confidence reports,” he said – a search for publically available information on the topic, then interviews with suppliers, manufacturers and fleets. “But rather than sharing experiences, which they don’t have because the technology is not yet in use, they are making predictions.”

The amount of automated control of a platoon’s second and subsequent trucks will likely increase from the current throttle and braking to steering and lane-keeping, Roeth predicted. “The technology will evolve” as it’s shown to be workable.

However, “Platooning is not autonomous trucking, and it is being improperly grouped with that,” he said. “Platooning still requires a driver in the second truck.”

Platooning is not exactly around the corner, but it will begin sooner or later, said those consulted in the study.

“I’m thinking 2018 to 2030 before we see platooning operations on the road," said an anonymous manager for a major truckload fleet quoted in the report. "There are still way too many studies that have to be done on this subject.” 

An executive summary of the report is here. The full report is here

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Tom Berg

Tom Berg

Former Senior Contributing Editor

Journalist since 1965, truck writer and editor since 1978.

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