Calibration, data consistency and model acquisition with laser stripers

Range data can play an important role in industrial inspection and quality assurance. We analyse the issues of calibration, stripe location and measurement consistency in low-cost, triangulation-based range sensors using structured laser light. We adopt a direct calibration technique which does not require modelling any specific sensor component or phenomenon, and therefore is not limited in accuracy by the inability to model error sources. We compare five algorithms for determining the location of the stripe in the images with subpixel accuracy. We describe data consistency tests based on two-camera geometry, which make it possible to acquire satisfactory range images of highly reflective surfaces with holes. Finally, we sketch the use of our range sensor within an automatic system for 3-D model acquisition from multiple range images. Experimental results illustrating the various topics accuracy are reported and discussed.