Computer vision-based displacement measurement with m-sequence target

Yi Ding Hu, Qi Xia, Rong Rong Hou, Yong Xia, Jian Yi Yan

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)


The development of image sensors enables the application of vision-based techniques to the non-contact displacement measurement of large-scale structures. The features of the physical targets are critical to the accuracy, stability and anti-interference of the displacement measurement results. In this study, a novel m-sequence target and the associated circular correlation processing technique are developed for real-time displacement measurement. The properties of the m-sequence as a pseudo-random sequence are introduced. The vision-based displacement calculation method is then derived from the correlation property of the m-sequence. The algorithms and measurement systems are integrated in the LabVIEW environment. To verify the anti-interference performance of the developed system, static and dynamic experimental tests are carried out with various forms of interference, such as partial occlusion, uneven illumination, out of focus and smoke effect. Experimental results indicate that the developed system cannot only accurately measure structural displacement, but also has outstanding anti-interference performance, even if 30% of the target is masked.

Original languageEnglish
Pages (from-to)537-546
Number of pages10
JournalSmart Structures and Systems
Issue number3
Publication statusPublished - Mar 2021


  • Computer vision
  • Displacement measurement
  • M-sequence
  • Structural health monitoring
  • Target tracking

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Computer Science Applications
  • Electrical and Electronic Engineering

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