Automatic Visual Inspection System (AVI): An overview
Automatic Visual Inspection is the combination of Machine Vision technology with Computer Vision science applied to the industrial sector. With reference to the pharmaceutical industry, the visual inspection technology is based on automated cameras and on complex vision algorithms that determine if the container is fit to comply with given standards by detecting:
- Presence of Foreign Particulate Matters (FPM)
- Cosmetic Defects
- False Fill Level and Product Color
Why AVI is important:
Automatic Visual Inspection is a mandatory practice for injectable manufacturers to guarantee both quality and patient safety. The finished products must be inspected by a visual inspection machine to identify and reject visible foreign matter contaminated parenteral containers and units displaying defects that could potentially affect product quality.
The inspection and detection of foreign particulate matter (FPM) is critical for quality control in powders, liquids, and lyophilized parenteral products used to cure patients. Machine vision inspection systems are configured to detect extraneous particles such as:
- fibers, dust (from environment)
- agglomerates, undissolved material (from product formulation)
- rubber, glass, plastic, metal (from packaging materials)
- metal from screen, filter material (from drug manufacturing process)
The international regulations for Visual Inspection are laid out in the following protocols:
- United States Pharmacopeia:
USP General Chapter <1>: “Injections”
USP Gen. Chap. <790>: “Visible Particulates in Injections”
USP Gen. Chap. <1790>: “Visual Inspection of Injections”.
- European Pharmacopeia § 2.9.20:
“Particulate Contamination: Visible Particles”
- EU GMP: Annex 1 – “Manufacture of Sterile Medicinal Products #124
- WHO Annex 6 – GMP for sterile pharmaceutical products #13.8
How the AVI method works:
For each inspected container, a collection of product images in sequence at 360° is acquired using high resolution cameras under designed illuminating conditions. Defects on the package are identified and/or measured by dedicated image processing algorithms and the package is classified as conforming or non-conforming accordingly. Non-conforming packages are automatically rejected. In case of detection of Foreign Particulate Matter (FPM) with liquid content: the container is first put into motion, then stopped, followed by the acquisition of product images by high-resolution cameras that record a series of images. With powder or lyophilized content, the container is put into motion and cameras record a series of images, in sequence, at different moments during rotation.
Finally, custom inspection can be provided too with each specific product peculiarity. Bonfiglioli Engineering’s AVI systems can detect:
- Foreign Particulate Matters from multiple origins.
- Wrong fill level and liquid color.
- Outside particle on lyo cake or powder.
- Lyo cake volume / color / form defects.
- Cosmetic defects like scratches, glass/plastic deformation, black-spot (burning point on the glass/ plastic surface) or marking defects as well as determining lack of package material, cracks, cap defects, rubber stopper absence, defective crimp, dents, flip off damages.
Bonfiglioli Engineering is continuously enriching its automated solutions with new devices on process optimization and sensitivity augmentation of measurement systems.