Robust vision-based controller design for laser cladding processes

In practical cladding processes, any small parameter variation may cause undesired geometry changes. Therefore, a fast and robust controller design is required to ensure the quality of the process. In this paper, a robust vision-based controller with a specified interval phase-margin performance for laser cladding processes is presented. First, a practical nonlinear laser cladding processes was modeled as a fuzzy parametric uncertain model. A fuzzy α-cut representation is used to describe the uncertain parameters of the process. By using the generalized Kharitonov theorem, the robust PI controller parameters can be obtained from the graphic k_P - k_I parameter plane. The simulation results validate that the proposed controller is not only robust to different operating conditions, but also exhibits a better dynamic response.