Estimating Product Development Project Duration for the Concurrent Execution of Multiple Activities

Many companies adopt concurrent engineering for their product development projects to reduce time to market. It is often the case that the multiple activities are overlapped in a concurrent engineering environment, while most of the product development research covers only the two-activity problems. The concept of degree of evolution has been proposed in literature to represent how close the unfinalized design of the downstream activity is to its final one, which is actually a measure of the real progress, reflecting the rework requirement due to overlapping. When more than three activities are concurrently executed, it is midstream activity whose degree of evolution is important, since it affects the rework duration for downstream and consequently the overall project duration. It is difficult to estimate the degree of evolution for midstream since involves has two uncertainties, one derived from incomplete information from upstream while the other from changing design information of itself. This paper models the degree of evolution for midstream activity taking into account the two uncertainties. On top of the model, this paper develops a methodology to calculate the project duration, which depends on the project managers’ decision on information transfer frequency and overlapping ratio, when three activities are concurrently executed. This paper is expected to help firms forecast the effect of management decision about concurrent engineering dealing with overlapping among multiple activities.