Functional Design And Function Switching Of Adaptable-function Mechanical Products

Adaptable-function mechanical products have obvious advantages over the general mechanical products,such as wide applicability,compact structure and being functionally expandable.Therefore,it is of great significance on the innovative design of adaptable-function mechanical products and making the general mechanical products adaptable.Current research on this regard is rare.To address this problem,this thesis carries out two aspects of research,one being a study on function-module division and the similarity between function structures of mechanical products,so to assist the adaptable-function product design.The other involves investigating the disassembly and assembly sequences of the adaptable-function product,so as to provide reference for the realization of efficient function switching of this kind of product.The detailed research contents are listed below.Firstly,it introduces the definition of function,function classification and function decomposition,and categorizes function into eight classes,including branch function,guiding function,connection function,size controlling function,switch function,supply function,signal function and support function.Then,the methods for development and combination of function chains are proposed.Combined with the directed graph,the product function structure model is established and transformed to a weighted directed graph,from which the reach-ability matrix of function structure module can be attained.Through the reach-ability matrix,the reach-ability of all the chains is easily known.In this way,the functional modules which compose the product will be clear.Finally,a case study is provided to demonstrate the feasibility of the method.Secondly,a functional design method for the adaptable-function mechanical product is presented at the basis of the existing conceptual design methods and the nature of the adaptable functions.Through analysis of the function structure and function modules of the product,it is found that similarity exists between different products,and then the concept of product function similarity is introduced.Based on the analytic hierarchy process(AHP),a functional similarity evaluation model is established to evaluate the similarity of the products.Then,an electric fan and blower is taken as an example to verify the functional similarity evaluation model.The similarity data of the corresponding function modules between two products provide useful assistance for judgment and decision on the adaptable-function product design.Finally,in order to enhance the efficiency of the function switching process of the adaptable-function mechanical products,it carries out research on the disassembly sequence and assembly sequence of the parts relevant to the switching process.The complexity of disassembly sequence is reduced with the help of the identification of sub-disassembly,and the support matrix is also proposed to ensure the stability during disassembling process.To acquire the interference information,the amended interference matrix based on the judgment of multi-direction path,and the aggregated interference matrix based on the method of bounding-box detection coupled with projection,are generated.The former obtains the disassembly sequences with information searching and simplification of matrix,while the latter goes further by applying Genetic Algorithm to obtain the optimal disassembly sequences.Both methods are verified by case study.