Vehicle safety technology started moving away from mechanical systems more than a decade ago. Collision warning and automatic braking systems use advanced sensors and technology that makes cars much safer for drivers and pedestrians as well.
The way these systems work is very simple. They combine cameras and sensors to detect objects in front of the car. In some cases, radars are used to detect the distance between the car and the vehicle in front of it. This is being monitored by the car ECU continuously as long as the car is turned on. Even when the car is standing still, collision warning and automatic braking systems are active.
The automatic braking system works along with side collision warning systems. Automatic braking is triggered by collision warning sensors. When the ECU considers that the vehicle might collide with another vehicle, obstacle, or pedestrian it engages the brakes automatically without the input of the driver. This system takes into account multiple factors. The ECU checks if the driver engaged the brake pedal, the speed of the car, and the distance towards the object.
It also detects the moving speed of the object in front to determine a safe braking distance. If the driver fails to react accordingly, the collision warning and automatic braking system take control of the car, assisting the driver and avoiding a traffic incident.
If the car detects an obstacle approaching or if an object is dangerously close, it will not engage the brakes if it determines that the current stopping speed determined by deceleration, how hard the brake pedal is pressed and distance to the object make it possible for the driver to avoid the collision unassisted.
All these systems make cars more complicated. Collision warning and automatic braking systems involve many sensors, cameras, processing power, and advanced software to work correctly. Technology has gotten cheaper which is why these technologies are now much more common.