How does the automatic wiper speed function works in cars?

Question

Like how does the car know how heavy is the current rainflow? What is the feedback loop involved?

In: 1

Answer 1

I’m not sure exactly how it works, but there is a sensor in my windshield and I believe it consists of a camera that registers drops on the glass, so the more drops, the fastest setting.

It’s a bit clumsy at times, btw, sometimes it will set itself to the fastest speed for some seconds with a little rain, and then slow down to one wipe every 3 or 4 seconds.

[Here is a nice explanation from the Volkswagen website](https://www.volkswagen.co.uk/en/technology/comfort/auto-rain-sensors.html)