Mark Steiner

Base Part Identification in Mechanical Assemblies Using Interaction Graphs for Redesign Toward a Star Architecture

This paper explores base part identification in mechanical assemblies using interaction graphs. It presents a methodology for analyzing and migrating toward a star architecture during product redesign, where the base part is the central element in the design upon which assembly variations can be configured, thus making it possible to migrate toward modular design architecture. This paper reviews past work related to architectural orientations, part interfaces, and part connectivity. A methodology for architecture analysis during product redesign is then presented using a computer mouse example.Copyright

Product Architecture Navigation Integration Tool: Redesign Towards Modular Architecture

Inherent to every product design and design process is the concept of architecture. Designers and engineers can use a product’s architecture as a roadmap towards achieving and maintaining a competitive edge in the rapidly changing global marketplace. Current engineering design tools such as computer-aided design (CAD) often focus exclusively on the geometric domain of product architecture and do not provide a convenient format or the tools for assessing product architecture. This paper describes tools that can represent product architecture in the form of two-dimensional graph layouts, called “interaction graphs.” These graphs display the arrangement of parts and their interfaces to other parts in an assembly, and they are useful for designers because they offer a direct display of the complexity and arrangement of a design. This is not apparent when viewing assemblies in a three-dimensional space, as in the case with solid modelers. Interaction graphs offer explicit insight into the modularity of a design because of the simplification from complex geometry to simple nodes and edges. This graph layout allows the designer to visualize the extent of design integration. Using graph theory tools and analysis, a designer can filter parts that are candidates for deletion and categorize the “base” part. With this knowledge and the functional requirements of the design, the alignment of the base part to the primary functions becomes an important concept when striving for efficient redesign. Cycles in designs that inhibit modularity can be targeted for elimination based on joint complexity, material type, relative motion, functional specifications, and other life cycle attributes.Copyright

An application of robotic cable harness bundling

Cable harnesses are used in various equipment including automobiles, airplanes, locomotives and computers. In the Cable Harness Design and Assembly System, cables are designed at a CAD workstation and the cable harness is built by a remote robot. This paper covers the bundling subsystem of the Cable Harness Design and Assembly System. This involved both hardware and software development. The hardware consists of the interface of the bundling tool to the robot controller and the circuitry for driving an optical sensor located at the end of the bundling tool for monitoring the cable height. The software developed consists of several programs, for processing the information coming from the CAD database and driving the manipulator through the process. The bundling subsystem relies on feedback from the sensor at the manipulator end effector for adapting to minor errors and for temporary suspension of the process when non-recoverable errors occur.