| As a branch of plastic working field, sheet metal forming possesses the important place in the industry field of automobile, aviation, instrument and so on. Its state of the art reflects industrial modern level of a country or region in some degree. Due to lack of the skill in real-time monitoring, identifying and predicting, the automation of sheet metal forming can only finish forming process in the light of pre-established work program and process parameters. When material quality and operating condition of manufactured object change or fluctuate, process parameters can't be automatically regulated. The intellectualization of sheet metal forming, which includes 4 basic elements, real-time monitoring, identification, prediction and control, is the crossing subject of control-science and sheet metal forming theory. According to the characteristics of the initial piece, utilizing physical quantities easy to be measured, material properties and friction coefficient can be determined in real-time, and then the forming process can be completed automatically with the optimal processing parameters. As a result, the intellectualization of sheet metal forming process is the higher level of new technologies such as press forming automation and flexible process system, by which not only can the feature of manufacturing technique be changed, but also the transformation of press equipment can be forwarded. It brings about the progress of sheet metal forming theory and improvement of analysis precision at the same time, it has the important significance for degrading sheet metal level, eliminating technology difficulty between die and equipment adjustment, shortening die setting time, improving productivity and the rate of finished products, and so on. Most workpieces are non-axial symmetry complex shape represented by rectangular box in engineering practice, so it has much academic value and significance to study intelligent control technology of deep drawing for a rectangular box.Based on the research achievements of intelligent deep drawing for an axis-symmetric part, the key technologies of intelligent deep drawing for a rectangular box are discussed, and the relevant issues to the process monitoring and identification model have been studied in this paper.Among the four basic elements required by intelligent deep drawing for a rectangular box, the establishment of the identification model of parameters and the prediction model of optimal technological parameter is dependent upon the level of understanding the forming law for a rectangular box. With the deformation characteristics of rectangular boxin deep drawing, the theoretic analysis of stress on deformation area has been obtained on the basis of the hypothesis that deformation law of shear stress zero-line is the same as the corresponding axial symmetric workpieces, which provides the theoretic basis for the identification of parameters and the prediction of fracture and wrinkling.The dominant factors influenced on deep drawing forming of a rectangular box have been analyzed by using theoretic analysis and finite element method (FEM) simulation, and then the identification model of parameters for a rectangular box is determined. The Levenberg-Marquarat is chosen as optimal algorithm of neural network whose topology structure is feedforward network, and Matlab language is to program. For the problem of sample data acquisition, the feasibility has been studied that FEM replaces some experiments to get sample data. Furthermore, the influence of sample data and hidden nodes on network convergence efficiency, precision as well as generalization has been studied. The strategy of stage identification with constant blank holder force is put forward as identification scheme for a rectangular box, by which the sum-squared error is stepped downward to l‰ The hybrid method of removing singular points and mean technique is employed to improve generalization precision.Real-time monitoring and control depend on the development of data acquisition (DAQ) technol...
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