Flaw finders

To ensure output remains consistent and the end-user benefits from good quality, manufacturers try to ensure that processes conform to tight specifications and products are checked for conformity before they leave the factory.

There are various methods of assessing whether 'product' is within specification or to be rejected, and many of these rely on visual methods where either people or a sensor of some sort automatically decides whether it passes or fails.

The outside of your car is important in terms of what is an acceptable level of surface finish. No-one wants a new vehicle with even fairly small scratches or dents. Manual inspection methods, where lamps are shone on the surface to detect faults, are still common but as in many other fields, technology is taking over.

'reflectControl' vision system, for example, uses deflectometry to compare a reflected image with the surface of an object, such as a car panel. The degree of difference of the reflected image to the real object is a measure of the surface finish on the part.