An Analysis of Uncertainty and Robustness of Waterjet Machine Positioning Vision System

  • D. M. Dziak Gdansk University of Technology
  • B. S. Jachimczyk Gdansk University of Technology
  • W. J. Kulesza Blekinge Institute of Technology
Keywords: Image cropping, object detection, vision system, waterjet machine, web camera


The paper presents a new Automatic Waterjet Positioning Vision System (AWPVS) and investigates components of workpiece positioning accuracy. The main purpose of AWPVS is to precisely identify the position and rotation of a workpiece placed on a waterjet machine table. Two webcams form a basis for the system, and constitute its characteristics. The proposed algorithm comprises various image processing techniques to assure a required identification precision. To validate the PVS identification quality, synthetic images were applied under various conditions. The analysis ascertains dependence of an object detection rate and accuracy on a size of cropping frame. Experimental results of the proposed PVS prototype prove that a combination of the vision algorithm and webcams is an alternative to dedicated expensive industrial vision systems. The two main components of AWPVS uncertainty, a machine component and PSV component are discerned and estimated.