Roundness measurement of cigarette based on visual information

Abstract

Roundness is defined as the degree that the cross section of an object is close to a theoretical circle. In the cigarette production process, the quality and production efficiency of a cigarette are directly affected by the roundness of the un-cut cigarette. To improve the current measurement method using a charge-coupled device (CCD) sensor and measure the roundness of cigarettes in the production line, a visual detection system composed of an industrial camera and a structural light is developed. The system’s roundness-calculation method is closer to the real environment of the cigarette roundness. In this visual system, the line-structure light shines on the cigarette with a fixed angle and height in a longitudinal section, forming a crescent-shaped spot when the industrial camera cannot capture the cigarette’s end surface. Then, the spot is analyzed using image-processing techniques, such as a median filter and ellipse fitting, after the industrial camera captures the spot. The system with a non-contact measurement style can meet the requirements of on-line cigarette detection with stable results and high precision.

Keywords

Roundness measurement / Ellipse fitting / Image processing / Visual detection system

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