RazerCam Smart Camera
g width="300" vspace="10" hspace="10" height="300" border="1" align="right" src="/userAssets/aiaUploads/image/EVT_Bandstahl_Inspektion_Zeilenkameras.jpg" alt="EVT Eye Vision Technology Presents RazerCam Smart Camera" />With the RazerCam smart camera series EVT now also has developed a surface inspection system, which can be used in all stages of the steel strip production. Especially due to the free-programmable FPGAs of the camera complex filters can be applied in real time and therefore also demanding surfaces, as in the steel production, can be inspected. There are two different systems, which are either equipped with a line scan camera or with a matrix camera. But also a combination of both camera types is possible.
The system allows the user to efficiently detect crucial errors on the entire steel strip surface. And then the system will classify the errors depending on shape and size according to the production titles such as roller dents, reel slide, etc. With the EyeVision evaluation software the system flexibly variable for the automated steel strip inspection during all process sections – from the hot-rolled strip to the cold roll. Additionally, thanks to the 2 ARM Cortex A9 cores, the RazerCam is applicable for every production speed.
The following errors are best detected at different process sections:
e.g. grave defects are best recognized on hot-rolled strips, but those defects are eliminated with etching; glue and periodic defects are best detected on thin sheet metal and on hot zinc dipped steel sheet errors such as dirt or zinc top drosses are easy to detect. Whereas scratches are best recognized on electrogalvanized steel strips.
To detect defects on steel strips a good contrast is essential. Therefore the illumination of the steel has a great influence on the detection of defects. The user has the choice between bright field and dark field illumination. With a bright field illumination the errors, which reflect or disperse light, are displayed dark on a bright background. Especially defects such as scratches and dents are easily recognizable in this light.
With a dark field illumination the errors are displayed bright on dark background. But as images in dark field illumination have to be amplified due to their low light quantity, the contrast is not as good as with bright field illuminations.
In general, the RazerCam offers the possibility to recognize and classify demanding surface defects. Thanks to the FPGAs of the RazerCam, the image inspection is done in real time and therefore is faster than to date.