This paper proposes a new integrated product design method for build-to-order production system based products, using the product family concept, which considers product performance, delivery lead-time and inventory cost. The development and discussion of this method uses a switchgear design problem as a concrete and practical design case. A build-to-order production system has been routinely applied to switchgear manufacturing, due to the requirements of small-scale production scenarios and diverse customer needs. However, if the risk of maintaining unsold inventory can be decreased, manufacturers can justify maintaining certain levels of versatile inventory on hand. In this paper, an inventory production system is applied to the switchgear production problem to shorten the delivery lead-time, and product family design is applied to reduce inventory cost. A three-objective optimization problem is formulated for this problem and a Pareto optimal solution set of the three objective functions is obtained to facilitate appropriate decision-making.
