Engineers at the Egyptian Center for Technology (ECT; Giza, Egypt) have developed an image processing system that can check if a vacuum is present inside juice bottles at the end of a production line.
Dr. Akml Nasr and his team from ECT developed the system to automate the processing of inspecting the bottles, a process which had previously been performed manually.
Nasr made use of the fact that the shape of the bottle cap varies depending on whether or not a vacuum is present inside the bottle. As such, the manner in which the cap reflects light will vary accordingly.
Hence, by applying a homogenous parallel light to the bottle cover and measuring the intensity of reflected light using a CCD camera, it was possible to determine whether or not a vacuum was present.
In operation, the presence of bottles on the production line is detected by a photocell which triggers the CCD camera to capture an image of the top of the bottle which is illuminated by a light source. The image is then acquired by a PC which processes the images using software developed using National Instruments (Austin, TX) LabVIEW.
If a bottle without a vacuum is detected by the image processing software, that bottle is rejected from the production line using a pneumatic pusher.
More information on the system can be found here.
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CIVision (Aurora, IL, USA) has designed a system that uses off-the-shelf cameras, lenses, and lighting components to inspect the neck and sidewalls of bottles.
The Silgan Equipment Company has developed a vision-based system to check whether bottles have been filled to an acceptable level and whether their caps are correctly placed and positioned.
-- Dave Wilson, Senior Editor, Vision Systems Design