Research on quality inspection for backside weld of tailored blank laser welding based on texture feature
In tailored blank laser welding, the quality of backside weld has a significant influence on mechanical properties of tailored blanks. The conventional method for the quality inspection of weld seams is based on the structured light deformation. However, the structured light deformation is not obvious in the backside weld which with dust disturbance, so the extraction of feature points is difficult only based on the structured light. A quality inspection system for backside weld of tailored blank laser welding was built and a new method based on combination of texture feature and structured light was proposed in this paper. In this method, the textural feature of the image was firstly analyzed, and then the image was segmented by the difference of the image texture feature between the weld region and the base metal region; finally, the zone of the weld were recognized based on voting strategy and the feature points were extracted. Experiments were conducted with this method, then the considered weld width was detected and other weld defects could also be detected. The experiment results showed that the proposed inspection system and method were effective for backside weld quality inspection of tailored blanks laser welding.
Vision-based gauge for online weld profile metrology
The development and application of an automated vision-based system for post weld inspection is discussed. The parameters of the weld bead profile have previously been measured manually using a variety of mechanical gauges. Such methods are slow, of dubious accuracy, and unsuited to online use. Here, structured light illumination, combined with fast, transputer based, image processing algorithms, provide weld profile metrology. A novel algorithm for analysing the laser stripe and finding the centre line of one pixel width is given. Speed is sufficient to provide online operation while accuracy is improved by a factor of ten. Results for butt and fillet welds are illustrated and an example of online operation provided.
Economics of General-Purpose Assembly Robots
Summary A study of the comparative economics of various automatic assembly systems using general-purpose assembly robots is described. In the study, use is made of a “typical” candidate assembly whose profile is obtained from statistical analysis of actual products submitted by interested companies. It is shown that the choice of assembly system and the various parts presentation methods depends on three main factors, namely: the annual production volume per shift, the number of parts in the product and the equipment payback period.