A Qualitative Survey on 3D Data Acquisition Techniques

Quality control is of almost importance in any industry. It requires online measurement and inspection system. Quality analysis has become a common requirement among the different systems developed for better service life of object. In the past, human vision has played a primary role in quality inspection and verification processes but using them the problems occurred like low working speed and prone to error. The solution to these problems has been the introduction of artificial vision-based inspection system. As a matter of fact, applications of these systems are nowadays widespread in many industrial sectors. Optical methods have the most important role for 3D data acquisition, and among those, the triangulation based method is the most important one. In this paper, various 3D data acquisition techniques are reviewed. From comparison of different techniques for distance less than one meter and for small scale objects laser triangulation technique gives better result. A triangulation-based method and system for high speed 3D and gray scale imaging and associated pre-processing of digitized information allows estimation or filtering of data height or depth and gray scale values. This estimation is based upon the confidence level of the information obtained from a camera and also based upon knowledge of the object structure and its reflectance characteristics.