Spatial sampling criteria for recognition of structures

Spatial sampling criteria based on a single view X-ray imaging system are proposed for recognition of the interior assembly structures of complex products. There must be a maximal rotary step for an object within which the least structural size to be tested is ascertained in advance. Rotating the object by the step and imaging it and so on until a 360° turn is completed, an image sequence is obtained that includes the full structural information for recognition. The maximal rotary step is restricted by the least structural size and the resolution of the imaging system. Based on the criteria, the first domestic X-ray digital test system has been developed and applied to the online inspection of objects containing complicated assembly structures.