| Adaptable-function mechanical system or product refers to the specific type of mechanical system which,by replacing or adjusting one or a few of its structural components,can deliver multiple functions.Existing research on this kind of product is rare.To better understand its characteristics and to provide assistance for its design and development,this thesis conducts some researches as listed below.Firstly,the thesis pointed out that there exists the unbalance usage of functions for the adaptable-function product and,based on the brief discussion of this phenomenon,the concept of function usage degree was proposed,and three types of function usage were summarized.Through exploring the relationship between function conversion,the concept of function conversion degree was put forward.Combined with the general set,the function usage model was constructed.At last,a case study of the multi-function plies were presented to demonstrate the construction procedure of this model.Secondly,the thesis carried out the research of structural correlation and functional coupling.Considering the fact that the existing research has failed to consider function usage,the thesis combined the function usage model with function-component incidence matrix,thereby,a method that can be used to quantify structural correlation and functional coupling under the consideration of function usage was proposed.Finally,an adaptable cooking machine was used as a case study to illustrate the feasibility of the methodology and the implement process,and based on results,some useful guidance was obtained for the design and development of the adaptable-function product.Thirdly,considering the fact that component change is often necessary in the design of the adaptable-function product,the thesis further studied the issues relevant to component change,with special emphasis on the component change risk.By taking into account the function conversion characteristics from product usage,it developed the change probability matrix of components and evaluated the change possibility of each component.Based on the existing research result about the change of single-function product,it studied the comprehensive change influence of the adaptablefunction product,where an influence matrix was obtained.Based on the change possibility and the influence between product components,the change risk of each component was also obtained and a method of component classification was subsequently put forward.Finally,a case study was presented to illustrate the feasibility of the proposed method and some guidance was concluded for the redesign of adaptable-function products.Lastly,based on the above research results,the thesis studied the methodologies for redesigning existing products for the adaptable one.By studying the behavioral process characteristics of the mechatronic products,it categorized the behavioral processes into basic behavioral process and teleological behavioral process,and pointed out the fact that it is due to the similarity of basic behavioral processes that makes it feasible to redesign existing products for a new adaptable-function one.Besides,the greater the similarity,the more feasible the redesign.After mapping the same or similar basic behavioral process to some structural components,it proposed a quantitative method for evaluation of the similarity of the components.By extracting the components with maximum similarity,it was able to identify the shared components,as well as to determine the products to be redesigned.Furthermore,it was noted that one of the most essential problems to be tackled in redesign is to design the interface between components.To this end,it proposed two rules to be followed as well as two methods to be applied.A case study of redesigning two mechatronic products,namely an electric ice-shaker and an electric vegetableshredder,for an adaptable-function product was presented at last to demonstrate the feasibility of the proposed redesign methodologies. |
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