Uber has ceased development of autonomous trucks to focus on its self-driving car technology, instead.
The company achieved the world's first commercial shipment delivered by a self-driving truck in 2016, with a vehicle that drove 120 miles along a highway in Colorado to deliver crates of Budweiser beer.
Uber began the programme when it acquired self-driving truck firm Otto, which was created by former Googler Anthony Levandowski - who was subsequently fired for stealing trade secrets from Google spin-off Waymo.
Driverless lorries aren't - yet - ready to replace people in the entire delivery chain. Current plans envisage them being used mainly on motorways, which are easier to navigate than small roads. They would pick and up and drop off their cargoes at waystations, where people would collect the goods and take them the final few miles for delivery.
Uber wanted its self-driving lorries to improve the safety and efficiency of the trucking industry. However, Advanced Technologies Group head Eric Meyhofer has now said that "We believe having our entire team's energy and expertise focused on [self-driving cars] is the best path forward."
In an email sent to staff and seen by TechCrunch, he added, "I know we're all super proud of what the Trucks team has accomplished, and we continue to see the incredible promise of self-driving technology applied to moving freight across the country. But we believe delivering on self-driving for passenger applications first, and then bringing it to freight applications down the line, is the best path forward. For now, we need the focus of one team, with one clear objective."
The company's self-driving car project has had its own problems.
In March, one of Uber's self-driving cars was involved in a fatal collision when it hit pedestrian Elaine Herzberg, who was crossing the road outside of a crossing zone.
Initial findings concluded that the company's software was not at fault, despite the car being slightly above the speed limit (38 mph in a 35 mph zone).
Three months later, the Uber safety driver herself was under investigation for apparently watching TV while the car was in motion.
A police report said that the crash was ‘entirely avoidable' if driver Rafaela Vasquez had been paying attention rather than - as records indicated - watching The Voice on her phone.
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