Member combination selection for product collaborative design under the open innovation model

•Developing a synergy effect-based member combination selection (SE-MCS) method.•This method considers the involvement of the customer in product collaborative design.•Identifying the synergy effect indicators by analysing the characteristics of product collaborative design under the open innovation model.•Quantifying the synergy effect indicators based on the interaction between members emphasized by collaboration.•This proposed method’s rationality and superiority is validated by illustrative example and results comparisons.