Automatic generation of 3d spiral tool path for incremental sheet metal forming of mechanical parts with complex geometry

Abstract

Incremental sheet metal forming is a flexible manufacturing technology that allows to form of various components on the same milling machine, without expensive tools. A hemispherical tool moves along a CNC-controlled tool path and deforms the sheet into the desired shape. The tool path has a significant role in the geometric accuracy of the final part. There has been very little research on the problem of the forming of sophisticated parts with asymmetric wall angles. This paper presents a new approach to generating optimized tool paths for single-point incremental sheet forming (SPIF). At first, a strategy is proposed for the automatic generation of a 3D tool path during forming in a single-step operation. Then, a systematic technique of creating intermediate shapes is investigated by defining tool paths interpolated from the final part shape. The proposed methodology is applied to form a hip cup prosthesis. This part has a complex asymmetric geometry with important angles, a multi-step approach is used. The proposed methodology to define the different tool paths was implemented in Matlab. A numerical simulation of the incremental forming process is performed to predict the final geometry of the aluminum sheet. A comparison of desired and predicted geometries shows the reliability of the proposed method.