Elon Musk’s Tesla has launched a limited rollout of its self-driving “Robotaxi” fleet in Austin, Texas in a major test of technology that the billionaire has promised will transform the company’s

The company has begun a test run of the driverless cabs, years after CEO Elon Musk vowed they would be on the road.

The service, initially for invited riders, offers limited hours and range. It's a potential sign of growth for robotaxis, industry observers say.