Robots are going to do many jobs for us. That applies to washing skyscraper windows. Israeli startup Skyline Robotics is working to replacing skyscraper window washers with robots. The robot uses its arms and brushes to clean the dirt and grime. Computer vision and touch sensors are used to help the robots operate safely.
Skyline Robotics uses a reverse osmosis approach for filtration. The above GIF shows these robots in action. More info is available here.