Design for manufacture Some product prototypes are easier to transition to mass production than others. For designs that are cheap to manufacture, manufacturability needs to be considered during development of the prototype, so that prototypes are not too expensive to manufacture well enough to perform adequately. The performance of the design can then be explicitly traded off against the cost of manufacture or, at least, indicators of the cost. It may be difficult to estimate manufacturing cost for a design, but there will be attributes of the design that can serve as good proxies for cost. Examples include the cost and volume of the required materials, and the number of separate parts that must be assembled to make the product.

Manufacture impacts evaluation In studying the performance tradeoffs between designs, it is important to note that the relevant performance metrics are not those for the ideal design, but for the manufactured design. For instance, in one project we studied the effect on performance of various manufacturing tolerances for slot-array antennas: how accurately positioned and aligned the holes are, how long the holes are, etc. It is important to know that, with affordable manufacturing techniques, performance loss due to manufacturing inaccuracies does not reduce the number of items rejected for poor quality to an uneconomic level. In the end, the cost of increased manufacturing accuracy should be properly traded off against the benefit of product performance gains, so that the decision-maker can identify the designs that still perform well when manufactured affordably.

Summary The precision of the process by which a design is manufactured impacts both its production cost and its resulting quality. The required precision should be considered as another part of the design. Then, many combinations of designs and precisions can be generated and evaluated for cost and performance. Or, if there are hard performance requirements, then cost can be traded off against the fraction of products that pass quality control checks. The result is an ability to minimize manufacturing cost while maximizing the expected performance of the manufactured product.