by Innovative Opel Light Communication System
The semi-autonomous Opel Grandland uses colors and symbols to signal to pedestrians. White LEDs have been replaced with cyan, magenta, and green in specific scenarios. The system was developed by Opel engineers in collaboration with Darmstadt Technical University.
As cars gradually take over more control functions, the issue of their interaction with the surroundings becomes increasingly relevant. Technologies are already ready to allow drivers to take their hands off the wheel and eyes off the road, but this creates a new challenge: how should the car communicate its intentions to those outside it. It is for this purpose that Opel created a Grandland prototype with a light system designed for direct communication with pedestrians.
The test model is equipped with a level 3 driver assistance system, which allows the person behind the wheel to disengage from driving under certain conditions. However, when the vehicle takes control, a new level of communication is needed to ensure that people on the street understand what the car is about to do.
Light as a Language
The Grandland prototype is equipped with a new system of cameras that can recognize objects and gestures, combined with an artificial intelligence-based “intent prediction” function. This allows it to better recognize real-world scenarios, for example, when a pedestrian appears from behind parked cars or when a child runs into the road chasing a ball.
When operating in level 3 autonomy (or higher), the SUV’s front and rear turn signals glow cyan. This color was chosen because it is not associated with any other vehicle function. When a pedestrian is detected in the car’s path, it begins to brake, and the LED headlights change color from white to magenta.
Additionally, on a small screen that usually displays the Opel Blitz emblem, a warning sign or a pedestrian symbol appears along with a stop gesture. When the car comes to a complete stop, the LEDs turn green, and a walking figure is displayed on the screen. In more complex situations, where the AI algorithm cannot decide on actions, the driver is asked to take control.
Rethinking the Purpose of Headlights
Philipp Röckl, Head of Global Lighting Development at Stellantis, explains the project’s logic:
Headlights certainly play an important role in improving road safety – but modern lighting systems are capable of much more. For example, light signals can be easily animated and used for animations. And the illuminated Blitz emblem on the Grandland can be replaced by a display, which can both show the illuminated logo and be used to communicate with other road users and pedestrians. By using existing lighting elements, we can easily add communication functions when we introduce autonomous driving features in our cars.
The Grandland with unique equipment and light functions has become one of a series of prototypes and production cars from other brands exploring this issue.
The model was created by engineers at Opel’s headquarters in Rüsselsheim (Germany) and was presented at the International Symposium on Automotive Lighting (ISAL) in Darmstadt. It is the result of collaboration between the Opel Concept Workshop and students from Darmstadt Technical University.
Stellantis and TU Darmstadt formed a strategic partnership for joint research into new lighting technologies back in 2022. As part of this collaboration, the automaker is currently funding the education of three PhD students in the university’s Department of Electrical Engineering and Information Technology.
Julissa Ley, Head of Innovation Projects at Stellantis, noted:
We specifically chose colors that are not yet associated with other vehicle functions to avoid misunderstandings. For example, the color red is intuitive, but it is already used for brake lights or car taillights. Cyan and magenta were carefully evaluated in terms of perception and are currently not present in any road situation. Both provide clear, unambiguous communication with other road users.
Opel
The development of such light communication systems is becoming a key step on the path to full vehicle autonomy. The implementation of unified visual signals, understandable to all road users, could significantly reduce the number of emergency situations in the cities of the future. Technologies similar to the one being implemented by Opel are forming a new standard of interaction between technology and humans in public space, where non-verbal communication will play a primary role. The success of such initiatives will depend on international standardization and widespread implementation so that everyone, regardless of country, can instantly recognize the intentions of an autonomous car.
