Research On Principle-structure-parameter Model Based Electromechanical Product Design

Entering the21st century, the requirement on rapidity, complexity,integration and individuation in electromechanical product design becomesmore and more important. As a result, product design theory faces newchallenges from several aspects. Current knowledge modeling methodsinterrupting the continuity of design knowledge, it is difficult to supportmulti-granularity, multi-domain knowledge representation; current designmodel isolating the design phases, it is hard for integration; current designmethod ignoring the system integrity of product design, it is unable to supporteffective design of functional topology and structural topology. This paperfocuses on the wide design stage from conceptual design to the beginning ofdetailed design (Pahl’s conceptual design and embodiment design), which is themost important design phase. Principle-Structure-Parameter Model is proposedto support the design events in this stage. Main content of this paper isstructured as follows:(1) Researched on knowledge representation based on Principle-Structure-Parameter Model. On the basis of three design phase division, i.e. functionalprinciple design stage, physical structure design stage and parametricembodiment design stage, based on differences in knowledge granularity andpattern between each stage, functional knowledge cell modeling, functionalcase modeling and structure parameter-behavior variable constraints modelingare applied to modeling and represent the knowledge in the three design stages.As a result, qualitative-to-quantitative transition knowledge representationbetween multiple design phases is achieved.(2) Researched on principle design method. Functional similarityreasoning is proposed for functional principle selection, functional flow morphology and transfer of functional morphology are investigated forfunctional topology design. Functional sketch is proposed to visualize principlesolutions. Evaluation method on principle solution is also discussed.(3) Researched on physical structure design method. Constrainedinclusive similarity algorithm is proposed for functional case selection.Functional topology to structure topology mapping based flow interfaceselection method is researched, as well as functional flow interface strengthbased mounting interface design. Evaluation method for physical structuresolution is discussed as well.(4) Researched on parametric embodiment design method. Functionalflow morphology based embodiment design trajectory planning method isproposed. Structure parameter-behavior variable coupling matrix based echelondimensionality reduction-partial solving method for structure parameter-behavior variable equations is investigated. A composite movement particleswarm algorithm is proposed to cope with “morbid” structureparameter-behavior variable equations. Assembly validation and optimizationof embodiment solutions is also discussed.(5) Prototype system development and theory application are implemented.A computer aided design prototype system named Design Synthesis Lab isdeveloped, which is based on Principle-Structure-Parameter Model. Themethods introduced in this paper are applied in design of electromechanicalsystem of automated numerical microscope to verify the effectiveness of thetheory.