Design automation of mechatronic systems using evolutionary computation and bond graph

The research of this dissertation is of significance because it is one of the first endeavors to address the challenging issue of design automation of mechatronic systems, at a time when mechatronics is emerging as an integrated and independent discipline of the 21st century. Just as Electronic Design Automation (EDA) has changed the face of design of electronic systems, Mechatronic Design Automation (MDA) is gaining more and more importance in addressing the ever-growing, competing challenges of the current market. In fact, design automation and optimization have become mainstream disciplines in the area of engineering design. The motivation of this research is two-fold. First, we want to find a way to generate a population of topologically open-ended design alternatives and provide for the designer, in an automated manner, a variety of satisfactory design candidates to choose among and trade off. Second, we want our method to be applicable not only in one physical domain, but in multiple domains or a mixture of them, as is required for design of mechatronic systems. To meet these ends, the capability of genetic programming, a special type of evolutionary computation techniques, to search automatically in an open-ended search space and the strong capability of bond graphs to represent and model mixed-domain systems are studied and ways to blend their merits in one unified approach are investigated. In this research, the BG/GP method, combining bond graphs and genetic programming, has been developed to automate the conceptual design process for general multidisciplinary mechatronic systems. Several design problems, in macro- and micro-domains, and in different physical domains, have been used as design examples to test the feasibility of the BG/GP approach. The analog electronic filter design problem shows the efficiency and effectiveness of the proposed approach. A vibration absorber design for a mechanical printer demonstrates that the approach can also be used for redesign and is very effective in exploring in an open-ended topology space and capable of providing designers with a variety of good design candidates for further analysis and tradeoff. Finally, a Micro-Electro-Mechanical (MEM) filter design problem shows that the BG/GP approach can be applied in a very general class of conceptual design problems with severe topology and/or parameter constraints. The results show that the BG/GP method is a powerful synergistic approach for automated, mixed-domain, and topologically open-ended conceptual design of mechatronic systems. A structured and hierarchical design methodology for Micro-Electro-Mechanical-Systems (MEMS) is also studied. MEMS are actually micro-mechatronic systems. The research of hierarchical evolutionary synthesis of MEMS in this thesis includes the system-level behavioral synthesis and second-level layout synthesis of MEMS. Preliminary results show that automated synthesis of MEMS is a very promising research area.