crazyal
Super Member
Never looking into how they work but we have laser curtains at work that stop any moving equipment if a person enters the restricted space. They get used anywhere there's contact between people and robots or other moving machinery. For example the silicon wafers get placed in a boat that holds 25 and that gets placed in a box while being moved from one location to another. Often times people will either place (or pick up) the boxes on a platform. The laser curtain will prevent the robot from touching the box as long as there's an arm or hand in the danger area. Otherwise they just have shields in place. Sets off all sorts of alarms so once people set the alarm off once they learn not to cross the line. Of course there's also the mandatory daily testing of the system. Years ago we had someone seriously hurt because someone defeated the system while working on it and accidentally forgot to reset it.