Dr. Xiaodi Hou, president of TuSimple, said in a statement:

"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. 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."

Long-haul drives that span almost a whole day requires two drivers, which could be a challenge to recruit. Hauling mail with a self-driving truck could address that problem. USPS is hoping to figure out how feasible it is to rely on autonomous trucks to transport mail across the country and to find out if the option can reduce fuel costs, improve safety and make its operations more efficient.