A method for reporting proximity in a factory floor environment, the method comprising: equipping a human with a first proximity detector (160, 300, 410, 1160) that is wearable; disposing a second proximity detector (160, 300, 420, 430, 1190) at a robot (140, 710, 720, 1150) that moves within a cell (132, 133, 1100) of the factory floor environment; determining a distance between the first proximity detector (160, 300, 410, 1160) and the second proximity detector (160, 300, 420, 430, 1190) by: determining a first position of the first proximity detector (160, 300, 410, 1160) based on a first signal transmitted by the first proximity detector (160, 300, 410, 1160), the first position being determined by triangulating based on a signal strength received at each of multiple sensors (120, 1170) in the factory floor environment; determining a second position of the second proximity detector (160, 300, 420, 430, 1190) based on a second signal transmitted by the second proximity detector (160, 300, 410, 1160) to the sensors (120, 1170) in the factory floor environment; and determining, as the distance, an amount of separation between the first position of the first proximity detector (160, 300, 410, 1160) and the second position of the second proximity detector (160, 300, 420, 430, 1190), based on the first signal and the second signal; and directing the first proximity detector (160, 300, 410, 1160) to provide a warning to the human if the determined distance is less than a threshold. equipping a human with a first proximity detector (160, 300, 410, 1160) that is wearable; disposing a second proximity detector (160, 300, 420, 430, 1190) at a robot (140, 710, 720, 1150) that moves within a cell (132, 133, 1100) of the factory floor environment; determining a distance between the first proximity detector (160, 300, 410, 1160) and the second proximity detector (160, 300, 420, 430, 1190) by: determining a first position of the first proximity detector (160, 300, 410, 1160) based on a first signal transmitted by the first proximity detector (160, 300, 410, 1160), the first position being determined by triangulating based on a signal strength received at each of multiple sensors (120, 1170) in the factory floor environment; determining a second position of the second proximity detector (160, 300, 420, 430, 1190) based on a second signal transmitted by the second proximity detector (160, 300, 410, 1160) to the sensors (120, 1170) in the factory floor environment; and determining, as the distance, an amount of separation between the first position of the first proximity detector (160, 300, 410, 1160) and the second position of the second proximity detector (160, 300, 420, 430, 1190), based on the first signal and the second signal; and determining a first position of the first proximity detector (160, 300, 410, 1160) based on a first signal transmitted by the first proximity detector (160, 300, 410, 1160), the first position being determined by triangulating based on a signal strength received at each of multiple sensors (120, 1170) in the factory floor environment; determining a second position of the second proximity detector (160, 300, 420, 430, 1190) based on a second signal transmitted by the second proximity detector (160, 300, 410, 1160) to the sensors (120, 1170) in the factory floor environment; and determining, as the distance, an amount of separation between the first position of the first proximity detector (160, 300, 410, 1160) and the second position of the second proximity detector (160, 300, 420, 430, 1190), based on the first signal and the second signal; and directing the first proximity detector (160, 300, 410, 1160) to provide a warning to the human if the determined distance is less than a threshold.