The United States Postal Service (USPS) has awarded self-driving truck company TuSimple a contract to perform five round trips, for a two-week pilot, hauling USPS trailers more than 1,000 miles between the Postal Service’s Phoenix and Dallas distribution centers.

During the duration of the pilot, a safety engineer and driver will be on board the truck to monitor vehicle performance and to ensure public safety.

For TuSimple, the company is expanding its autonomous operations beyond Arizona, as it debuts its self-driving technology in Texas. TuSimple will run a series of its self-driving trucks for 22 hours each, which includes overnight driving, along the I-10, I-20 and I-30 corridors to make the trip through Arizona, New Mexico and Texas.

According to TuSimple, the freight that travels along the I-10 corridor makes up 60 percent of the total economic activity in the United States. With strong demand from other customers for runs between Arizona and Texas, TuSimple expects this route to be a central one for the company.

“It is exciting to think that before many people will ride in a robo-taxi, their mail and packages may be carried in a self-driving truck,” says Dr. Xiaodi Hou, founder, president and chief technology officer, TuSimple.

“Performing for the USPS on this pilot in this particular commercial corridor gives us specific use cases to help us validate our system, and expedite the technological development and commercialization progress.”

The entities note that self-driving trucks are ideal for long-haul routes with short turnaround times, such as this 22-hour journey, because these routes are normally accomplished with driving teams of two. It can be difficult to recruit driving teams for several reasons, including the overnight driving requirements, the need to share close quarters with another person and a significant truck driver shortage, as the American Trucking Association (ATA) points out that the driver shortage could reach 175,000 by 2024.

TuSimple wants to establish the first driverless operations, so that human drivers can be freed to focus on the shorter, more dynamic and closer to home routes.

Meanwhile, the USPS is exploring how realistic it is to use autonomous delivery vehicle technology to reduce fuel costs, increase safe truck operation and improve its fleet utilization rate through longer hours of operation.