Abstract: A time computing model with its corresponding optimization method is presented for the overlapping and iteration between design activities in concurrent product development process. The design activity groups are divided into coupling and non-coupling activity blocks based on the programmed design structure matrix. According to the direction of information flow, rework time of each design activity caused by overlapping is calculated in turn. Then the time model of product development is formulated. Given cost constraint, the problem of shortest development time is transformed into constrained optimization problem, and a corresponding algorithm for this problem is proposed. The results of application example show that the time model and optimization method are effective.

Key words: Concurrent design, Design structure matrix, Optimization method, Time model