What kind of robot recently attacked a woman in South Korea?

This probably isn’t what Elon Musk was talking about when he warned of robots someday endangering the human race. A woman who had been taking a nap on the floor of her home in Changwon, South Korea, was awakened when her vacuum cleaner robot rolled over her hair and refused to let go. The woman, who was not seriously injured, called paramedics after being unable to extricate herself.