Dynamic programming based repeat inspection planning

Quality control systems can be divided into process control and product control. Process control is accomplished using process-control techniques such as control charts and process targeting. Product control is achieved by inspection plans. Inspection plans play a vital role in product control. In this paper we present a Vitebi Beam Search dynamic programming algorithm to determine the inspection sequence of multi-characteristic critical components and the number of repeat inspection for each characteristic. The model of the inspection plan used here considers the case of several classification of a product by inspector and accounts for possible misclassifications by the inspectors. The algorithm searches for a solution that minimizes the total cost of inspection per accepted component. The total cost includes the cost of false rejection of good items, the cost of false acceptance of an item which is either reworkable or to be scrapped, the cost of inspection, and the cost of rework.