Our series on the Future of Transportation explores innovations and challenges that affect how we move around the world.

A self-driving eighteen-wheeler traveled between Dallas and Atlanta in March. It traveled more than 6,300 miles and made four round trips.

The five-day drive demonstrated the enormous potential of self- driving trucks. It would take more than 10 days for a traditional truck to deliver the same cargo.

The technology isn't yet ready to realize its potential, as shown by the drive. Every day, a new team of specialists were put into the cab of the truck, so that someone could take control if something went wrong. The drivers grabbed the wheel.

Companies in the trucking industry are eager to reap the benefits of self-driving trucks, as tech start-ups like Kodiak have spent years building and testing them. At a time when the global supply chain is struggling to deliver goods as efficiently as businesses and consumers are 888-609- 888-609-

Getting these trucks on the road without anyone behind the wheel is the most difficult part of this quest.

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There is a long way to go before trucks can drive on their own. They want to deploy self-driving trucks on highways that are easier to navigate than city streets.

The chief executive of Embark said that highways are a more structured environment. You know where the cars are supposed to go. The people are in lanes. They are going in the same direction.

They play to their strengths by being restricted to the highway. Tiredness, distraction and boredom are the biggest problems for long haul truck drivers, according to Mr. Rodrigues. TheRobots don't have a problem with that

This is a sound strategy, but it will take years of development.

Technical is one of the challenges. Companies are still working to ensure they can respond to less common situations, like a sudden three-car pileup, despite the fact that self- driving trucks can handle most of what happens on a highway.

He said his company has yet to perfect evasive maneuvers. He said that if there is an accident in the road in front of the vehicle, it has to stop. Most companies won't remove safety drivers from their trucks until at least 2024. Regulators in many states will need to approve it.

Changes will need to be made across the trucking industry when it comes to the deployment of these trucks.

In moving goods between Dallas and Atlanta, the truck did not go into either city. It took a drive just off the highway to get to the spots where it could refill its tanks. The last mile is when traditional trucks pick up the cargo and drive the last leg of the delivery.

Companies need to build a network of transfer hubs in order to deploy autonomously. Pilot is a company that operates traditional truck stops across the country. These are places where truck drivers can take a break. They hope that they can serve as transfer hubs.

The industry can't afford to build this kind of infrastructure from scratch. We have to work with the infrastructure.

They will need more drivers for the short haul if they want to make long-haul drivers obsolete.

Drivers will happily move from one job to another, according to executives. The turnover rate among long-haul drivers is 95 percent, which means the average company replaces nearly its entire work force each year. The job keeps people away from home for a long time. They can stay closer to home if they switch to city driving.

A recent study by researchers at the University of Michigan questions if the transition will be as smooth as people think. Truck drivers are paid according to the distance traveled. A shift to shorter trips could reduce wages.

Some drivers think they can't make as much money driving in cities as they can in towns. Some people don't mind giving up their time on the highway.

Cannon Bryan is a long-haul truck driver from Texas. I wasn't born there. I didn't grow up in the city. I don't like to drive in the city. I like to pick up a load in Dallas and drive to Grand Rapids.

Self-driving trucks are hard to build and deploy. It costs hundreds of million of dollars a year. Federal regulators revealed that one of TuSimple's trucks had been involved in an accident. Aurora, a self-driving technology company with a particularly impressive background, is facing challenging market conditions and has floated the possibility of a sale to Apple or Microsoft, according to a report.

New questions are raised if these companies can get drivers out of their vehicles. Driverless trucks will handle roadside checks. When a truck pulls to the side of the road, how will they warn other drivers? How will they deal with tire problems?

Electric trucks powered by battery will eventually be accepted by the industry, and this will raise more questions for self-driving trucks. How will the batteries be charged? Self-driving trucks will be able to run 24 hours a day if this is not changed.

Steve Viscelli is an economic and political sociologist at the University of Pennsylvania who specializes in trucking. Many of the questions about what needs to change can't be answered yet. We are going to have to look at reality.

Technical and logistical solutions will be offered. When things go wrong, Embark plans to build a roaming work force of "guardians" who will locate trucks and call for repairs.

It is good news for the labor market that this technology will create jobs. More jobs will be lost than gained, but this won't happen soon. Long-haul truck drivers will have a long time to prepare for a new life. There will be gradual roll outs.

The chief executive of Forward Air, a trucking company that just started a test with a self-driving truck, said that it is five years away.