Automatic Optical Inspection, or AOI for short, is a further development of machine vision. As a video-based inspection method, it can be used in various fields and now in almost all sectors of industrial production. Image processing methods are used to find and report defects in production and other goods. AOI systems, also known as vision systems, are frequently used in food and pharmaceutical production, but also in the electronics, plastics, automotive, and aerospace industries.
Areas of application that particularly benefit from the system are goods receiving, picking, assembly and shipping. Depending on the area of application, the target varies.
AOI in order picking
The aim of Automatic Optical Inspection in order picking is to detect defective components that have been delivered. The confirmation in the warehouse management system takes place after the picking list has been processed. Errors in picking occur due to incorrect locations, inventory errors or gripping errors. On the one hand, these hinder the following processes in production, on the other hand, they lead to inventory discrepancies. Therefore, the use of AOI is one of the most effective and important facilities for quality assurance. This ensures that the warehouse worker is directed to the correct place as well as the removal of the correct material.
The AOI in electronic manufacturing and manual assembly
Automatic optical inspection is used, among other things, for inspection during the manufacture of printed circuit boards and electronic assemblies, as well as for the assembly of printed circuit boards. The AOI independently inspects the PCBs for defects using several high-resolution cameras and reports them. The 2D camera system photographs the assembly from above and tilted from the side at a 45-degree angle.
When the AOI system analyzes an image of a printed circuit board, it looks for a variety of specific features, such as:
- Printed circuit board reference points
- Presence of the components
- Component placement (displacement)
- Polarity
- Reflectivity of the solder joints
- Labeling patterns (such as barcodes)
AOI systems have become an important part of manufacturing. With Automatic Optical Inspection, continuous traceability of production is guaranteed.