Model-Based Design of Self-Correcting Forming Processes

Abstract

In this paper, a self-correcting strategy for a metal forming process is presented. This strategy entails continuously observing the properties of the product and ensuring that these properties stay in the required tolerances. This reduces the scrap rate and the need to adapt the configuration of the machine manually, both aspects leading to an increase of the productivity and efficiency of the process. For the development of the strategy, a structured design method for mechatronic systems is adapted. During the whole development process, it uses intensively mathematical models of system dynamics to ensure a high quality of the results. There are two commonly used model types to describe the behavior of a forming process: finite-element models and multibody system models. For the development of such a mathematical model, the process has to be examined. It is analyzed regarding its disturbances, influences and possibilities to take action. In this paper, the bending-process is modeled as a multibody system. It describes the most significant influences and is fundamental to develop the self-correcting closed-loop control. The presented model includes a good compromise between computation time and accuracy. After introducing the structured developed closed-loop control, the implementation and the results are presented.