In-process adhesive bead inspection with stationary cameras?
The optical inspection of adhesive beads in-process has many advantages. It is fast and requires no additional process time. No additional inspection positions have to be approached with the robot - the inspection takes place directly during application. This is often realised with a sensor head in the direct nearness of the nozzle (e.g. with the product Cyclospotter).
Where, however, accessibility to the application nozzle must be maintained or hot processing or nozzle temperatures prevent this, as in hot melt or hot butyl applications, VisionTools offers a solution of an in-process inspection with stationary cameras. With this method, cameras (usually three) and illuminations are arranged at a greater distance from the application nozzle.
When there is only a small contrast between the application compound and the background, such as in hotmelt applications, or when the temperature of the substrate or workpiece is a quality criterion, thermal imaging cameras can also be used. A combination of thermal imaging camera and colour camera enables additional inspections and a position check based on distinctive geometries on the workpiece.
The position, width and interruptions are checked. Only one inspection software is used for all our adhesive bead in-process inspection systems. In practice, application speeds of 500 mm/s are achieved.