Household robots use light sensors to find invisible crumbs

The next generation of household robots is moving beyond simple vacuuming to handle delicate chores like folding laundry and tying trash bags. Using dual arms with twenty-eight points of flexibility, these machines can mimic the precise grip of a primate to handle fragile objects. When it comes to floors, they use near-infrared spectroscopy—sensors that analyze how light bounces off surfaces—to detect ninety-two percent of crumbs and bacteria that are invisible to the naked eye.