If an obstacle is detected downwards, the screen slightly moves up and makes two further attempts to reach the lower end position. After the last failed attempt, the motor moves the screen in the protection position.
If the obstacle is only present during the first or the second run, the screen will reach successfully the lower end position. So the motor can clearly distinguish between a real obstacle, such as a watering can, or a simple gust of wind.
If the screen moves up, the sensitivity is significantly reduced to ensure that the upper position can be reached safely though the wind has come up.