In automated assembly procedures, it is essential that the individual parts are fed into the process with the correct lateral orientation, e.g. when positioning molded covers on distribution boxes. Because they are printed after the marriage process, these square covers must always arrive at the installation position with the same edge leading. With the aid of an image processing system from Vision & Control it is possible to reliably check the orientation of these covers – even in situations where space is tight and the clock rate is high.
The heart of the inspection system is the smart pictor® N-403M, which is smaller than a cigarette box. In addition to an innovative 0.3 megapixel image sensor, the monochrome camera also offers a powerful dual-core Cortex-A9 processor from ARM. This means that all image processing takes place directly in the unit itself. Thanks to the integrated Ethernet interface and web interface, the system can be operated from any PC or tablet in the same network.
In our example, a vicotar® VCN 1.8/35mm entocentric lens is used for the optical system. A combination of four short diffuse bar lights from the vicolux LDL14 series provides the necessary high-contrast illumination. They are fastened directly to the lens with the aid of adapters.
Thanks to the pre-installed test sequences, setting up the inspection routine is a matter of just a few steps – with no need for deeper programming skills. After acquisition of the image, the first step is to determine the center point of the cover based on the four holes in the cover, which appear darker in the image. From this, the program then uses the function “Probe > 360° shape search” to detect the orientation of the cover molding.
If the cover is in a rotated position, this is corrected in a downstream rotation station.
The inspection works reliably with different cover sizes and colors.