Editor's pick: Originally published June 17.

In early April, a tightly spaced procession of big tractor trailers drove across Europe, linked wirelessly to one another to harmonize braking and acceleration, a demonstration of autonomous driving's potential for the trucking industry.

The project, organized by the Netherlands on behalf of the European Union, was meant to show how "platooning" -- the reduced, controlled spacing between trucks in a long line -- reduces fuel consumption and traffic congestion, while improving safety.

The dozen or so trucks belonged to Volkswagen (VLKAY) and Daimler (DDAIF) , as well as Volvo AB, the Swedish truck maker, and Fiat Industrial SpA's Iveco unit. The exercise suggested that advanced driver-assistance systems, powered by digital technology, can be developed for the benefit of trucks as well as cars.

Peleton Technology of Mountain View, Calif., has been a developer of platooning systems, in which one lead driver can supervise or drive a string of several large trucks.

While most of the attention in advanced mobility has been centered on driverless cars from Alphabet's  (GOOGL - Get Report) Google unit, ride-sharing ventures like Uber, and most of the global automakers, the trucking and shipping industry are pressing forward as well.

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If large trucks can be equipped to operate without drivers, the eventual impact on the shipping industry could be substantial, said Lior Ron, formerly of Google and a founder of Ottomotto LLC, a Silicon Valley startup that's developing systems to retrofit trucks. Anthony Levandowski, one of the founders of Google's self-driving car project, also is working on Ottomotto.

"Trucks are unsexy," he said. "That's why we're doing it. It is old technology, and a huge market with a lot of deep issues around cost. But first and foremost, there's a big societal component. Trucks cover 5.6% of all highway miles but cause 9.5% of all fatalities, and about half of truckers are away from home 200 nights a year, sleeping in parking lots and rest areas."

Ottomotto has begun testing autonomous technology on three Volvo AB trucks. (Volvo has no connection to the passenger carmaker of the same name.)

Drivers for 18-wheelers are a major component of the U.S. labor market, according to Census data. Hence, any major technological shift that reduces their number would surely upset -- and possibly stimulate opposition from -- labor unions such as the Teamsters and Longshoremen.

Driving a truck has always been considered a vocation that requires skill, training and good judgment, with substantial potential for technological aids to reduce the fatigue and danger of long hauls and sleep deprivation. In 2013, the U.S. passed rules mandating more rest for drivers and limiting the time they can spend behind the wheel.

Still, the American Trucking Association estimated that 50,000 jobs for drivers today go unfilled, the rigors and tedium too great to attract enough qualified candidates. One day soon, one or two drivers could be supervising a long parade of autonomous trucks, the tasks of actual driving left to advanced software and sensors.

Doron Levin is the host of "In the Driver Seat," broadcast on SiriusXM Insight 121, Saturday at noon, encore Sunday at 9 a.m.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.