Center extraction deviation correction of SMD-LEDs in the target-based vision measurement system. (20th February 2017)

• Record Type: Journal Article
• Authors: Ma, Yueyang; Zhao, Hong; Gu, Feifei; Bu, Penghui
• Is Part Of: Measurement science & technology. Volume 28:Number 4(2017:Apr.)
• Publication Date: 2017-02-20
• Subjects: error analysis -- center extraction -- machine vision; Physical measurements -- Periodicals; Scientific apparatus and instruments -- Periodicals; Equipment and Supplies -- Periodicals; Science -- instrumentation -- Periodicals; Technology -- instrumentation -- Periodicals; Mesures physiques -- Périodiques; Physical measurements; Scientific apparatus and instruments; Periodicals; 502.87
• DOI: 10.1088/1361-6501/aa5bfa
• Languages: English
• ISSNs: 0957-0233

Abstract

Abstract: Surface mounted device-type light emitting diodes (SMD-LEDs) are commonly utilized as feature points in target-based vision measurement systems (T-VMSs) due to their high luminance. The non-uniform characteristics of said luminance introduce deviation errors in image center extraction, however, which degrades the positioning precision of the T-VMS. In this study, we first analyzed two factors responsible for deviation errors: The deflection angle between the LED's normal direction and the observation direction, and the distance between the LED and the observer. We then established a correction method based on a lookup table to compensate for deviation errors according to these two factors. We also analyzed the correction direction of the deviation error. We applied the proposed method in an actual T-VMS to confirm its feasibility and effectiveness, and found that it does indeed correct deviation errors effectively.