May 16, 2024

Fraunhofer FHR: Headlights of the Future - Digital, Trends, Science & Research, Autonomous Driving (Road Traffic), Road Safety |  news |  Bus planner - technology - public transport

Fraunhofer FHR: Headlights of the Future – Digital, Trends, Science & Research, Autonomous Driving (Road Traffic), Road Safety | news | Bus planner – technology – public transport

What is the human eye and ear, is the autonomous car sensor. But the increasing number of sensors requires more space – and this somewhat goes against the wishes of designers. As part of the Smart Headlight project, researchers from five Fraunhofer Institutes, including the Institute for High-Frequency Physics and FHR Radar Technology, are installing some sensors in headlights – and they want to combine optical light, radar and lidar.

The goal of the project is to develop a sensor-integrated headlight for driver assistance systems where different sensory elements are combined with adaptive lighting systems. This way, the sensors should better recognize objects on the road, especially other road users such as pedestrians. For example, the lidar sensor is used in electronic brake assistants or in remote control systems.

We integrate radar and lidar sensors into the headlights, which are there anyway and which ensure optimal transmission of optical sensors, light sources and freedom from dirt. (Tim Fradenhoven, scientist at Fraunhofer FHR)

Using lidar (light detection and ranging) sensors, the time between the emission of the laser pulse and the receipt of the reflected light is measured, so that the distances can be determined very precisely. The researchers face a number of challenges in their project: The light falling on the road from the headlight must not be affected by two additional sensors – but the necessary LEDs are located at the back of the headlight.

So the researchers arranged the lidar sensors on top and the radar sensors on the bottom of the lamp shade. However, the rays of both sensing systems must take the same LED light path. In addition, all rays have different wavelengths. According to Freialdenhoven, these three wavelengths must be grouped together on the same axis, i.e. coaxial. The advantage of this arrangement is that it takes up less space than sensors arranged side by side. When combined with LED light and lidar light, a specially coated mirror ensures that both rays of light are reflected on one axis.

The same thing happens with the second so-called collector, where the LED light, lidar light and radar are combined. Since radar sensors are already prevalent in the automotive sector, the dual-assembly device is to be designed so that manufacturers can continue to use existing sensors without making any modifications. The combination of optical, lidar, and radar systems is essential because: “each system has its strengths, but also its weaknesses,” says Friehldenhoven. According to him, optical systems reach their limits in optically poor conditions of visibility, such as fog and dust.

On the other hand, radar systems look almost unimpeded by dense fog waves, but their classification ability is not very high. Radar can distinguish between people and trees, for example, but cannot match the capabilities of lidar classification.

We are also integrating data from radar and lidar – providing maximum added value, particularly in terms of reliability. Follow Favorite

The patent has already been filed and the researchers say they are currently working on building a prototype. You see that the possibilities for sensor integration of driver assistance systems have expanded significantly. Smaller lighting modules, more compact lidar sensors and integrated radar sensors should enable multi-sensor concepts to be implemented – particularly for autonomous driving with increasing design requirements and at the same time limited installation space.

In the future, autonomous systems should not only be able to recognize a person, but also analyze their speed, distance and the angle at which they are standing relative to the car.