A representation model for the solving-time distribution of a set of design tasks in new product development (NPD)

Given the potential risks of new product development projects (NPD), the characteristics of the design tasks solving-time distributions are critical for their effective management. In OR we need to find what operational characteristics of design tasks may delay projects. Other researchers already identified the technological novelty, the magnitude of the design tasks, the interactions between design tasks in an NPD project, and the balancing between projects among the most important causes of the unpredictability of the design tasks lead times in NPD projects.We develop a simple queuing model incorporating all these four factors, to estimate the solving-time distribution of a finite set of design tasks assigned to a team of engineers during an NPD project. Using the Kolmogorov–Smirnov goodness-of-fit test, we show the model to be statistically equivalent to several sets of experimental data from a micro-lithography firm.This model assumes an ordering of the design tasks allocated to the team of engineers according to some optimality criteria of the upper management levels. In the more general framework of mathematical control of NPD, our model can be integrated in hierarchical planning and control solutions.