In just five years, TuSimple has become the biggest and most visible developer of self-driving trucks, raising more cash and putting more robotic big rigs on the road than any rival. High-profile customers including UPS have contracted to let TuSimple haul their cargo on the highway. Executives have forecast heady revenue and predicted that fully automated, driverless trucks are in sight. 

Instead, TuSimple has fallen short of expectations, hampered by the same technological challenges that have afflicted other developers of self-driving vehicles. It had predicted several hundred million dollars of revenue by this year, but instead acknowledges revenue is minimal, according to the company’s financial projections reviewed by The Information. And it has fallen short of its timeline for removing human backup drivers, repeatedly pushing that goal into the future.