The research in this dissertation attempts to provide theoretic approaches and design systems to support engineers who are located in different places and belong to different teams or companies to work collaboratively to perform product development.The second challenge is addressed by developing a collaborative design process modeling technique based on Petri-net. Petri-net is used to describe complex design processes and to construct different design process alternatives. These alternative Petri-net models are then analyzed to evaluate design process alternatives and to select the appropriate process.In this dissertation, three major challenges are identified in realization of a collaborative design paradigm: (i) development of design method that supports multidisciplinary xi design teams to collaboratively solve coupled design problems, (ii) development of process modeling techniques to support representation and improve complex collaborative design process, and (iii) implementation of a testbed system that demonstrates the feasibility of enhancing current design system to satisfy with the needs of organizing collaborative design process for collaborative decision making and associated design activities.New paradigms, along with accompanying approaches and software systems are necessary to support collaborative design work, in a distributed design environment, of multidisciplinary engineering teams who have different knowledge, experience, and skills. Current research generally focuses on the development of online collaborative tools, and software frameworks that integrate and coordinate these tools. However, a gap exists between the needs of a distributed collaborative design paradigm and current collaborative design tools. On one side, design methodologies facilitating engineering teams' decision making is not well developed. In a distributed collaborative design paradigm, each team holds its own perspective towards the product realization problem, and each team seeks design decisions that can maximize the design performance in its own discipline. Design methodologies that coordinate the separate design decisions are essential to achieve successful collaboration. On the other side, design of products is becoming more complex. Organizing a complex design process is a major obstacle in the application of a distributed collaborative design paradigm in practice. Therefore, the principal research goal in this dissertation is to develop a collaborative multidisciplinary decision making methodology and design process modeling technique that bridges the gap between a collaborative design paradigm and current collaborative design systems.To overcome the first challenge, decision templates are constructed to exchange design information among interacting disciplines. Three game protocols from game theory are utilized to categorize the collaboration in decision makings. Design formulations are used to capture the design freedom among coupled design activities.The third challenge, implementation of collaborative design testbed, is addressed by integration of existing Petri-net modeling tools into the design system. The testbed incorporates optimization software, collaborative design tools, and management software for product and process design to support group design activities.Two product realization examples are presented to demonstrate the applicability of the research and collaborative testbed. A simplified manipulator design example is used for explanation of collaborative decision making and design process organization. And a reverse engineering design example is introduced to verify the application of collaborative design paradigm with design support systems in practice
