SINGLE IMAGE LASER TRIANGULATION SYSTEM FOR 360° EXTERNAL INSPECTION OF CYLINDRICAL SHAPED OBJECTS USING INVERSE TRIANGULATION ALGORITHM

Abstract. This paper proposes a new Laser Triangulation System (LTS) that allows an 360° external inspection for each acquired image using two planar mirrors, one laser line projector, and one camera. The new measurement algorithm is based on the inverse triangulation in which the analysis is made from 3D object space to image space, the opposite of traditional LTS algorithms, with laser peak detection in favourable directions even in an image with multiple reflections of the object. Measurement system principle, calibration and metrological evaluation are described based on simulated experimental data and 3D reconstructions examples. Uncertainty for a 20 mm plain plug gauge measurement was ±0.07 mm for 95.45% confidence.