A methodology for modelling manufacturing costs at conceptual design

This paper describes a method for modelling costs throughout the design phase of a product's life-cycle, from conceptual to detail design. The timely provision of cost data facilitates the quantitative evaluation of designs through a cost function. This approach to design evaluation has the advantages of allowing management to make more accurate bid estimates, encouraging designers to design to cost and reducing the amount of design rework, hence reducing the product's time to market and controlling product cost. The cost modelling strategy adopted incorporates the use of knowledge-based and case-based approaches. Cost estimation is automated by linking design knowledge, required for predicting design features from incomplete design descriptions, to production knowledge. The link between the two knowledge paradigms is achieved through the blackboard framework of problem solving which incorporates both case-based and rule-based reasoning. The method described is aimed at innovative design activity.