Self-driving cars are often described as replacements for human drivers, but a General Motors patent filing shows how they could be used to train new ones.

First spotted by Motor1, the filing with the United States Patent and Trademark Office (USPTO) is titled "Methods and Systems to Autonomously Train Drivers." It proposes putting student drivers in autonomous cars and using the vehicles' onboard systems to coach and grade them.

In place of a human instructor, sensors would track a student's control inputs and provide real-time feedback, according to the document. Sensors used for this would include lidar, cameras, and GPS. So many of the same sensors that allow a self-driving car to navigate its environment, in other words.

Cruise Origin driverless vehicle

Cruise Origin driverless vehicle

In the filing, GM said the benefits of automated driver training would include lower costs and easier scheduling. It would essentially put human driving instructors out of a job, however.

As for why driver training would still be necessary in a world of self-driving cars, GM said people may still want to drive for personal satisfaction. Autonomous cars may also need human assistance in certain situations, so people will still need to be trained to take over control, the automaker noted.

Automakers often patent new technologies without clear plans for commercialization, but in this case the patent is also dependent on the widespread use of self-driving cars. While GM is developing autonomous-driving tech through its Cruise division, and has shown a purpose-built autonomous vehicle called the Origin, that is still likely a long way off.