A low-cost vision-based system for displacement analysis in earthquake research

Measuring linear and angular displacement with high accuracy requires expensive equipment and may interfere with the measurements due to sensors weight and size. In this paper, we propose a low cost vision based approach for measuring linear & angular displacement that can make the earthquake research more affordable. To keep detecting process as fast as possible and meet real-time demands, a typical marker with a peculiar color inside chooses and all instructions performed by Intel CVLib filters. So according to the tests, if the minimum requirement are met, the proposed method can detect marker up to 25 frames per second. Finally, a prototype software implemented to analysis functionality and accuracy of proposed algorithm. The results shown that this vision-based method can achieve accuracy of 0.1mm, with an off-the-shelf three pixel per millimeter, and it can be perfectly used instead of traditional instruments such as LVDT.