iRVision Error Proofing - http://www.fanucrobotics.com/products/vision-software/robot-vision-software.aspx
Error proofing is a multifaceted approach to verify quality or sort based on product part. The example has a conveyor that transfers parts to a camera triggered by a sensor. The system allows the correct part to transfer with no changes and identifies the wrong product by flashing a red LED light. The video includes iRVision screen shots that show the images captured by the camera.