Engineering design is a model-based activity which describes the product’s multiple perspectives. With process model, we can also lead concurrent engineering activities. Both product and process models have been largely investigated. This paper aims at describing knowledge-based heterogeneous models chained to trace the design rationale that is the fundamental requirement to afford changes management. This knowledge chain supports the progressive by least commitment convergence of the space of design solutions. This rationale allows designers to go back and forth in the decision-making process. Moreover, the progressive convergence increases the possibilities for designers to integrate new knowledge toward innovation.