Environmental Perception

How a vehicle senses the environment

Prior to perform any action, a vehicle has to be aware of its environment. As humans, while driving, we mostly rely on our visual sense. Therefore, its evident to provide a vehicle with multiple cameras, e.g., to perform lane detection.

Is this enough to drive autonomously?
In some scenarios, visual perception come to its limits: extreme weather conditions such as fog or heavy rain, certain light conditions such as direct sunlight or night, and occlusion restrict our visual representation of the environment. Also human drivers use other senses to evaluate certain situations: e.g., the emergency vehicle is often detected by means of noise prior than by our eyes. In addition to cameras, mainly, radars, lidars, and ultrasonic sensors are used. GPS sensors are in use for positioning. Data from sensors differ, e.g., in quality. Thus, in a first step, redundant sensors are needed. Afterwards, to get a consistent view, sensor fusion is essential: it allows to combine strengths of sensors to compensate the weaknesses of other sensors.