Adaptive camera calibration in an industrial robotic environment

ABSTRACT

One of the fundamental difficulties that arises when attempting to use computer vision in dynamic environments is that camera calibration coefficients must be adjusted as the relative distances between camera and target object change, causing refocusing to occur. Such situations arise frequently in robotic environments in which the visual sensor is mobile or the target objects are in motion. This paper presents a method for computing camera calibration coefficients for cases in which it is known that the relative motion between camera and target object is a translation along the optical axis, as in cases for which the camera is moving directly toward or away from an object of interest. The calibration technique is straightforward, involving only the solution of linear equations. It is demonstrated that, within the context of a spatial reasoning system, inclusion of the calibration method can improve the relative accuracy of spatial inferences by one to two orders of magnitude.

REFERENCES

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.2 ARTIFICIAL INTELLIGENCE
      I.2.1 Applications and Expert Systems
          Subjects: Industrial automation

Additional Classification:
  F. Theory of Computation
  F.2 ANALYSIS OF ALGORITHMS AND PROBLEM COMPLEXITY
      F.2.2 Nonnumerical Algorithms and Problems
          Subjects: Geometrical problems and computations; Computations on discrete structures

  I. Computing Methodologies
  I.2 ARTIFICIAL INTELLIGENCE
        I.2.10 Vision and Scene Understanding
            Subjects: Motion
      I.2.9 Robotics
          Subjects: Sensors

General Terms:
Algorithms