See with Siemens

(A&D) has developed an image-processing system for the automatic inspection of coloured objects.

Siemens claims the Simatic MV220 coloured-surface sensor can perform 30 test operations per second and that its plastic/metallic housing in IP65 is suitable for use directly on the machine in rough industrial environments.

The system is used primarily in production engineering as well as in applications in the packaging and food & beverage industries. The new system is "trained" rather than programmed, so that the user requires no special training.

The digital camera for inspecting the objects, which is equipped with a CMOS chip, has a resolution of 640 x 480 pixels. The infinitely-adjustable lens system can be used to adjust the display field from 40x30 to 200x150 millimetres and the distance-to-object range from 50 to 250 millimetres.

An incandescent light source and a laser-based alignment system which helps support manual alignment have also been integrated. The control and display unit is equipped with four operator buttons, a four-digit text display and LED indicators. Digital inputs and outputs are used to integrate the image-processing system in the plant automation system.

The system can learn as many as sixteen test models. Model changes during operation result in brief changeover times. The "training" of the models is based on specifiable characteristics of one or more "good objects". It is possible to inspect both stationary and mobile objects, a good/bad decision being made on the basis of preset threshold values. A test result of "OK" or "Not OK" is output over two digital outputs.