Reliable Occupancy Sensor for Modified Straddle Carriers

Each year, over 14 million twenty-foot equivalent units (TEU) of containers are transported into the U.S. from approximately 700 ports around the world. To facilitate the screening of containers, modified straddle carriers with plastic scintillators, neutron detectors, and NaI detectors (spectroscopic detectors) travels through rows of containers to perform radiation scanning. Portal monitors survey radiation during the traversal of the containers in the detection zone based on the signals from the occupancy sensor. In the proposed program, Linea Research Corporation will develop a robust occupancy sensor system that can reliably detect the following parameters: 1) Occupancy of the container within the detection zone; 2) Identification of the edges(ends) of separate containers even when the containers are placed with ends contacting each other; 3)Determination of straddle carrier speed with provision for an alarm if the maximum speed is exceeded; and 4)Determination of the relative position (offset) in relation to the center line between the sensor panels with provision for an alam if threshold distance is exceeded. The sensor system will be designed to be robust enough to operate in the presence of various sources of noise such has direct sunlight, loud sounds, and vibration.