Apparatus and methods for door curtain breakaway detection

An apparatus comprising:

• a door curtain;
• a track to guide movement of the door curtain between an open position and a closed position relative to a doorway;
• a plurality of tags distributed along the door curtain, the tags to move with the door curtain;
• a scanner disposed on the track, the scanner to detect a series of the tags as successive ones of the tags in the series pass the scanner as the door curtain moves between the open position and the closed position;
• and
• a controller to identify when the door curtain is in a breakaway state based on a failure of the scanner to detect given ones of the tags in the series when the given ones of the tags are expected to pass the scanner based on a position and movement of the door curtain.

An apparatus comprising:

• a door curtain to move along a guide positioned adjacent a doorway;
• RFID tags distributed along a lateral edge of the door curtain;
• an RFID scanner to detect ones of the RFID tags when the ones of the RFID tags are in proximity to the RFID scanner, different ones of the RFID tags to be in proximity to the RFID scanner at different times associated with different heights of a leading edge of the door curtain;
• and
• a controller to:
• control movement of the door curtain;
• monitor a position of the leading edge of the door curtain;
• determine a position of a first tag of the RFID tags based on the position of the leading edge of the door curtain;
• and
• determine the door curtain is in a breakaway state when the position of the first tag passes the RFID scanner and the RFID scanner does not detect the first tag.