US-based supply chain management company United Parcel Service (UPS) has revealed that it is testing self-driving tractor-trailers in Arizona.

The self-driving service commenced in May this year and follows a minority investment made by UPS venture capital arm in the autonomous driving company TuSimple.

As part of the ongoing testing, the goods are being transported on a North American Freight Forwarding route between Phoenix and Tucson.

Comprising a driver and engineer in the vehicle, the testing will help evaluate whether the trailers are capable of enhancing the UPS network’s service and efficiency.

Data such as distance, the journey time taken for trucks to travel autonomously, and safety will be monitored by both parties.

The minority investment complements the existing commercial relationship between UPS and TuSimple for purchased transportation services.

According to TuSimple, the use of self-driving tractor-trailers is expected to cut the average purchased transportation costs by 30%.

UPS chief strategy and transformation officer Scott Price said: “UPS is committed to developing and deploying technologies that enable us to operate our global logistics network more efficiently.

“While fully autonomous, driverless vehicles still have development and regulatory work ahead, we are excited by the advances in braking and other technologies that companies like TuSimple are mastering.

“All of these technologies offer significant safety and other benefits that will be realised long before the full vision of autonomous vehicles is brought to fruition, and UPS will be there, as a leader implementing these new technologies in our fleet.”