Fault-Tolerant Weld Line Detection Using Image Processing and Fusion of Execution Monitoring Systems


Quality control, cost reduction and above all, human and environmental safety are great reasons that stimulate the investments in technologies like automatic inspection. The automatic inspection of weld lines in storage tanks is of special interest, due to the fact that such tanks are currently used to store harmful products. For a reliable inspection it is necessary to accurately detect the weld line relative position and orientation with respect to the inspection robot. In this paper, the development of a system to perform weld line detection and estimation in storage tanks is proposed. The system uses visual information to perform the detection task and a fault-tolerant estimation process, main contribution of this work, to increase the confidence and performance of the detection system. The fault-tolerant estimation is based on the \(\alpha \)\(\beta \) filter and on a knowledge-based execution monitoring system, constructed through the fusion of two subsystems: a data-based and a model-based fault detection systems.

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The authors wish to thank CNPq and CAPES for the financial support that made possible the realization of this project.

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Correspondence to Lucas Molina.

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Molina, L., Carvalho, E.Á.N., Freire, E.O. et al. Fault-Tolerant Weld Line Detection Using Image Processing and Fusion of Execution Monitoring Systems. J Control Autom Electr Syst 24, 70–80 (2013). https://doi.org/10.1007/s40313-013-0016-3

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  • Weld line detection
  • Fault-tolerant estimation
  • Image processing
  • \(\alpha \)\(\beta \) filter