Because of the relative speeds involved, a driver confronted with this situation has only fractions of a second to react. A collision is almost unavoidable and the outcome is often fatal.
Germans call wrong-way drivers "Geisterfahrer" (ghost drivers) and some motorway entry roads in the southern state of Bavaria have been fitted with large bright yellow warning signs as part of a test project. A nationwide electronic warning system is still in the pipeline.
ZF's 'Wrong Way Inhibit' is a further development of the X2Safe algorithm. - All images from dpa
The new set-up from Friedrichshafen-based ZF is called "Wrong Way Inhibit" and at the moment it is still at the concept stage. It is a further development of the X2Safe algorithm announced by the firm last year.
ZF will present its "Vision Zero Car" fitted with the system at the Frankfurt Car Show in September, although it may be years before it becomes commercially available. Component maker Bosch is working on a similar system.
"On the road towards this reality, ZF's all-electric Vision Zero Vehicle is reaching important milestones in the transition phase from assisted to autonomous driving," said the company.
Reporters from German motoring magazine Autobild tried out a Volkswagen Touran van fitted with ZF system and they were impressed.
To test the vehicle's reaction, a journalist drove the family van onto the motorway and right past a prominent stop sign. Warning bells and whistles were sounded in the cabin and the car was brought to a halt swiftly and safely.
Around 20 people are killed in Germany by wrong-way motorway drivers every year and transport researchers say such accidents are among the most serious of all. Radio stations broadcast some 1,800 wrong-way driver alerts every year, most of them at the weekend.
Interestingly enough, age has nothing to do with wrong-way driving - only 10 per cent of wrong-way drivers are aged over 65, a survey found.
The safety system is ZF's contribution to the European Union project Vision Zero, which is designed to drastically cut the number of fatal road accidents down to zero by 2050.
So how does the ZF system work? The feature uses detailed navigation maps and is also linked to what the company calls driver distraction assist, a laser-based interior camera with learning capabilities that helps keep the driver's eyes on the road.
The system reacts as soon as there is an indication that the driver is about to enter a road in the wrong direction – whether due to distraction, poor visibility in bad weather or disorientation.
If the driver heads for a motorway exit instead of an entry road - as marked on the car's map - the system kicks in as soon as the person at the wheel activates the indicator stalk and starts a turn.
The false move triggers a battery of warnings. A visual warning light shows up on the central display panel, an audible buzzer goes off and gets louder, and the driver's seatbelt tightens up.
Finally, the steering wheel vibrates and stiffens up the steering, making it hard for the driver to continue travelling the wrong way.
If the driver still fails to respond, the car takes over. It switches on dipped beam headlights and activates the vehicle's hazard warning lights before moving the car at slow speed to a safe stopping position at the side of the road.
If there is suitable evasive space or the driver goes into reverse, the ZF system will allow the driver to operate the vehicle along the roadside in order to get out of the hazard zone.
