System and method for three-dimensional scan of moving objects longer than the field of view

A vision system having a 3D camera assembly, arranged as an area scan sensor, and a vision system processor receiving 3D data from images of an object acquired within a field of view (FOV) of the 3D camera assembly, the object being conveyed in a conveying direction through the FOV and the object defining an overall length in the conveying direction longer that the FOV, comprising:

• a dimensioning processor that measures the overall length based upon motion tracking information derived from the conveying of the object through the FOV in combination with a plurality of 3D images of the object, acquired by the 3D camera assembly in a sequence with predetermined amounts of conveying motion between the 3D images;
• a presence detector, associated with the FOV, that provides a presence signal as the object is located adjacent thereto,
• wherein the dimensioning processor, in response to the presence signal, is arranged to determine if the object appears in more than one image as the object moves in the conveying direction, and
• wherein the dimensioning processor, in response to information related to features on the object, is arranged to determine if the object is longer than the FOV as the object moves in the conveying direction;
• and
• an image processor that combines the information related to the features on the object from consecutive image acquisitions by the 3D camera that generates aggregate feature data, so as to determine overall the dimensions of the object in a manner free of combining discrete, individual images into an overall image.