Research And Development Of Assembly Time Modeling And Calculation System For Complex Mechanical And Electronic Products

Time quota is an important basis for enterprises to estimate costs and arrange production.With the change of market environment,enterprises put forward new demands on the efficiency and accuracy of time quota.However,the traditional empirical estimation method are still adopted by an enterprise in Nanjing to formulate time quota at present.For complex mechanical and electrical products,it is laborintensive work to calculate assembly time.In response to these problems,this paper studied the method of assembly time calculation.The main work of this paper is as follows:1.Assembly time influencing factors were analyzed in following respects: attributes of the parts,assembly topology structure and assembly processes.Assembly time oriented information model was established,and the data structure of the model was defined.Automatic extraction method of assembly information in 3D model was studied.2.In the early stage of product design,a method of estimating the assembly time based on the optimized SVM algorithm was proposed.The SVM algorithm and its parameter optimization method based on Genetic Algorithm were studied.Taking the radar frog leg as an example,the influencing factors of the assembly time were analyzed.The estimation model of the assembly time of the products based on SVM was established.Finally,the accuracy and efficiency of the method was verified.3.At the beginning of the production of the product,an assembly time calculation method based on 3D process was proposed.The assembly operation was decomposed into three basic steps: loading,positioning and fastening.The model of assembly time of each step was established.The 3D assembly process based on MBD was analyzed.The information in the 3D assembly process was extracted by using xml parsing technology,and the automation calculation of assembly time was realized.Finally,the accuracy of this method were verified by an example.4.Assembly Time Modeling and Calculation System for Complex Mechanical and Electronic Products was developed.After the requirement analysis,the overall architecture of the system was designed.The system database of the system was designed.The assembly time calculation rules library was established for users to modify the rules.Finally,JSP technology was used to develop the system.