Inspection and repair strategy in automated assembly systems

In most automated assembly systems, each product is inspected after every assembly operation and, if it is found to be defective, it will be repaired or scrapped immediately. This ensures the quality of the outputs of the systems, but it also causes a short stop of the assembly line. This paper shows that the number of short stops can be reduced by installing inspection stations and repair stations strategically. Then, an optimizing problem of placing these stations under a given assembly sequence is formulated and an algorithm is given to this problem. Further, the problem of not only placing these stations but also determining the assembly sequence is formulated and an algorithm to solve the problem is developed. Finally, numerical examples are given to illustrate the efficiencies of the algorithms.