This poses a challenge to developers of automated driving systems who, logically, aim to provide a safe, convenient trip for everyone involved. Continental rose to the task by conducting extensive test drives in four very different parts of the globe.
To gather real-life data under everyday conditions, Continental's Cruising Chauffeur system – which enables hands-free, feet-free driving – was submitted to lengthy test drives in China, Europe, Japan and the United States. Two Continental employees rode in each automated car. Behind the wheel, an experienced test engineer checked whether the system fit in at all times, and was ready to intervene if something unexpected happened. In the passenger seat, a development engineer monitored the system’s data-processing and noted irregularities of the road.
It is absolutely crucial for an automated vehicle to interpret its surroundings accurately. To this end, Continental has created the Comprehensive Environmental Model (CEM), which is fed input from three different sensor types mounted on the vehicle to provide a comprehensive 360 view around the vehicle: radars, a 2D cameras and 3D Flash LIDAR. Each sensor collects data in order to create a comprehensive real-life image that, in many ways, is superior to the human eye. But in some cases, the system has to be told what this data means. A prime example: regional differences in road markings.
In the U.S., the team drove – or rather, was driven – from Detroit, Michigan to Jacksonville, Florida. Because hard winters in the north often cause road markings to fade, they became more visible as the team traveled south. That’s just one small example of regional variation within a single country, but international differences also became apparent as the journey continued. While a solid yellow line in the U.S. marks the side of the road and should not be crossed, such lines in Germany indicate a construction site. And on a German autobahn, white lines are spaced differently than on roads in Spain, France or Italy. All of these variations need to be taken in account and the CEM must be able to understand the different regional interpretations.
Japan is among the world’s few industrialized countries with left-hand traffic, creating yet another set of challenges for the system. As our Cruising Chauffeur traveled from the busy city of Yokohama into the south and then back along the west coast, it had to deal with dense traffic, and other complex issues. Another regional difference, the Chinese habit of indicating a lane switch not by blinking, but with a short beep on the horn. To understand the regional differences better and ensure proper understanding all the test vehicles had an internationally mixed team who could shed light on these regional peculiarities.
One important lesson of these drives is that the human factor cannot be dismissed, since the driving styles of people-operated vehicles around the automated cars vary greatly. For instance, Germans have a reputation of being fast yet disciplined drivers, while the French are said to be a bit pushy behind the wheel. On the wide, often empty highways of the North American heartland, blinking is seen as optional at best.
In the course of the project, the presence of international passengers revealed another all-too human aspect: the Human Machine Interface (HMI), the communication bridge between vehicle and driver, should always be adapted to the user's country. Americans appreciate bulky instruments and screens, while German drivers tend to like them clean, elegant, and almost hidden. In China and Japan, on the other hand, the cockpit just can't be flashy enough for drivers – the more sound, colors and animation, the better. Such aesthetic details must be addressed when preparing automated cars for roads around the world.
For Continental, the automated test drives delivered important insights and a great deal of new knowledge. A coordinated effort of this sort, conducted in such a wide variety of places and conditions, was a first in the industry. While Continental develops the parameters of the Cruising Chauffeur software in 11 international locations, the goal is not “one size fits all” – but rather, to create a system that will always observe regional traffic laws and peculiarities safely and correctly, all over the world.