Quality control by artificial vision

Citation

(2006), "Quality control by artificial vision", Assembly Automation, Vol. 26 No. 1. https://doi.org/10.1108/aa.2006.03326aaf.007

Quality control by artificial vision

Quality control by artificial vision

Keywords: Quality control, Electronics industry, Image sensors

Part of the British engineering group Meggitt plc, PIHER's plant located in Northern Spain manufactures potentiometers, encoders and switches for automotive and consumer markets.

Until recently, the products manufactured by PIHER were verified manually, which gave way to errors on the production line and shipment returns from clients. To eradicate these problems and fall in line with other companies in the electronic sensors market, PIHER decided to integrate a vision system to guarantee 100 percent defect-free products (Plate 6).

Plate 6 Cognex vision sensors ensure zero defects at PIHER

PIHER experts learned about Cognex vision systems through a Spanish partner integrator: ikusmen Visión Artificial, S.L.

The objective of integrating vision onto the production lines was to verify the integrity of the potentiometers being manufactured. The criteria to be monitored were established as the following.

Correct riveting; complete pivots; rotor without imperfections; correct angle orientation of the rotor; central track without defects; detection of potentiometers marked in red.

The application process begins with the potentiometers leaving the line on a conveyor belt. A sensor detects the part's movement and activates a signal so that the vision system captures the image. The vision equipment makes the verification and if it detects a flawed potentiometer, the expulsion system is triggered to eject the part. For traceability purposes, the vision system also records data from inspected parts, and can even categorise this data, e.g. non-conform parts by each type of defect.

The vision system in place at PIHER, which can inspect up to 100 potentiometers per minute, consists of an In-Sight 1000 camera, an illumination system and a computer for configuration tasks and visualisation of results.

Due to the integrated vision system at PIHER, the company are achieving their objectives, which include ensuring 100 percent verification on the production line and automatically eliminating defective potentiometers.