Towards product evolution: from the perspective of user knowledge

In the field of engineering design, design for evolution is an economic and effective tactic to deal with changing customer requirements, in which the quantification of the product evolution degree between adjacent product generations is vital. Under the knowledge economy environment, user knowledge includes personalised experience, which can be used to develop competitive and creative products. The evolution of user knowledge can be applied to monitor product evolution to a certain extent. Thus, an evolution model is established to quantify the product evolution degree by integrating a user knowledge network, the Girven–Newman algorithm, latent Dirichlet allocation, an information axiom, and an evolution map. These methods are adopted to determine the knowledge topics for each product generation and to quantify the evolution degree of the current product generation, while the inheritance relation between each pair of knowledge clusters in two adjacent product generations is considered. Finally, the evolution process modelling of iPhone is performed as a case study to evaluate the effectiveness of the proposed method. The results show that the evolution map and curve to visualise the evolution process, and the evolution patterns and mechanisms are deduced to assist designers in forecasting future trends.