A Library-Based Concept Design Approach for Multi-Disciplinary Systems in SysML
Author: Kruse, Benjamin
Supervisor: Prof. Dr. Kristina Shea;
Institution: ETH Zurich, Switzerland
Page(s): I-XVIII; 1-172
Conceptual design of modern multi-disciplinary systems that combine mechatronics with services for the creation of product service systems (PSS) is a crucial phase of the product development process. Yet, existing design support is not sufficient despite fundamental developments such as model-based systems
engineering (MBSE) and the modeling language SysML. SysML is a standardized, multi-purpose graphical modeling language for specifying, designing and analyzing complex multi-disciplinary systems. However, it is still not widely used in mechanical and mechatronic design. The problem addressed in this work is how to better support multidisciplinary concept design. The presented approach integrates formal generic design libraries that can be reused, modeling guidance and integrated simulation for concept evaluation. More specifically, it implements the Functional Basis (FB), elements from a commercial simulation tool and a service catalogue in SysML libraries to offer a foundation of proven design knowledge together with multisolution patterns.
The first library is for functional modeling with the FB. It defines operatorflow formulations of functions for formal and solution-neutral functional decomposition. The second library provides elements from an adjunct multiphysics simulation tool to support behavior modeling as well as the planning of concept simulation in SysML. The third contributed library offers formalized service catalogue elements to support modeling of the service domain. These libraries, together with an additional structure library, provide generic elements for reuse to support concept design, while allowing inter-model traceability to link aspects from different disciplines and levels of abstraction. The additional multisolution patterns formally capture multiple alternative concept solutions to solve recurring design problems. Since they are based on solution-neutral functions, they can offer multiple potential solutions in one pattern. The solutions are partial models that cover various aspects, for example functions, behavior or structure. Their contribution is the enabled reuse of common coherent subsystems beyond single library elements. The research is conducted using the Design Research Methodology (DRM) including initial descriptive studies in the form of a case study and a conducted user study to evaluate the created support. The case stud demonstrates the concept design approach through the development of a 3D printer model that uses the libraries and solutions from patterns. The 3D printer model not only contains mechatronic aspects, but also complementary services and representations of two alternative kinematic designs that are simulated. Evaluation of the approach in the user study focuses on the function library and shows that the approach results in greater use of the FB and improved model quality. The presented work contributes a new approach to formal modeling with reuse of SysML models for supported multi-disciplinary concept design. It also serves as a basis for future additional computational support, e.g. automated design synthesis using the generic and formal design libraries.