Measurement of the circumference mean radius using image processing techniques


In this paper, the measurement of the mean radius of a circumference drawn on a A4 paper sheet was performed using image processing techniques available on the OpenCV package. Seventeen distinct pictures were taken, from which 136 different mean radiuses were obtained. The adopted procedure produced repetitive results with standard deviation of 0.4 % of the mean radius value. The mean radius obtained with the procedure presented an error of 0.5 % compared to the nominal value printed on the sheet. It is important to mention that uncertainties are associated to the printed circumference. No careful investigation of those uncertainties was carried out, but considering the caliper used for the measurements and the thickness of the circumference line, an estimative of the expanded uncertainty is 0.8 % of the nominal value of the 30 mm drawn radius.


MARTINS, Gabriel Borelli; SAITA, Marcelo Tadao. Medição do raio médio de uma circunferência utilizando técnicas de processamento de imagem. Revista IPT, Tecnolgia e Inovação, v.4,n.14,p. 24-36, ago., 2020.

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