Hi Ericgibbs,
The warning and protection field can be configured with it's own software. Usually the warning field is larger than the protection field. When the AGV is running and if the scanner sees something in the warning field it beeps to warn people. But quite often in a work place it's a noisy environment and so people might not hear it. If the AGV keep moving along and the scanner detects something in the protection field it will turn off the relay/ contactors which supply current to the motor and the AGV will stop and prevent it from hitting the person.