An autonomous driving mode that will take some of the strain off of drivers during long trips should arrive in Tesla cars in the next few weeks, PCWorld reports.

Earlier this year, CEO Elon Musk promised the feature as part of a "summer" update, and while Tesla will miss that deadline by a couple of weeks, it is about to roll it out.

The company has been testing the software for several months on long drives, including from its Silicon Valley headquarters to Seattle. It keeps the car safely in lane and adjusts its speed to allow for other vehicles, akin to an autopilot for the car.

Describing the system in March, Musk said it relied on ultrasonic sensors that cover the area around the car to a distance of about 5 meters, as well as a forward camera and radar.