This is exactly what the Tesla does. It periodically "checks" that you are there by prompting you to hold the steering wheel (requiring a firm grip, not just ha

This is exactly what the Tesla does. It periodically "checks" that you are there by prompting you to hold the steering wheel (requiring a firm grip, not just hands on the wheel). If you don't, the car slows to a stop and disables autopilot for the remainder of the drive.