The new Audi A8 has been showcased in Barcelona and rather than going fully automated, it features a self-driving system that relies on the human passenger for support.

Audi’s driverless car development team have spent many years showing the vehicle how to drive safely on the road. However, their real focus was on the human-machine interface that makes it hard to switch between human and machine.

If the vehicle knows when it needs support and senses that the human is not paying enough attention, it pesters them with visual and audio cues. If these things don’t work, the car will tighten the seatbelt and pumps the brakes. The vehicle will then turn its headlights on, stop, and unlock the doors.

Audi developed that sequence by subjecting many people on multiple continents to tests in simulators. The network can also be optimised for some chosen users, tweaking the car’s reaction based on the individual in the car.

The A8’s gives enough importance to humans, and this can make a good model for other firms. Some have started: Cadillac’s Super Cruise feature uses a camera to make sure the individual is ready to take control.

The new Audi A8’s steering wheel knows when it is being touched. It sees the driver with a facial-recognition cam in the instrument cluster, so it knows who’s at the wheel at all times and so can adapt to that person’s needs and personalisty, for example.

Many years from now, when fully driverless cars are widely available on the roads, these stopgap measures won’t be necessary, Audi said.

A major advantage to developing human-machine hybrids is that it builds a framework for answering an interesting question with implications far beyond vehicles: As increasingly intelligent machines come to life, how should they interact with humans?