Design and modeling of integrated Hall-effect sensor based on-line thickness measurement device for incremental sheet forming processes

The use of Numerical Control and computers in manufacturing has enabled the development of new sheet forming processes. One of these flexible processes is called Incremental Sheet Forming (ISF) in which deformation is localized by the movement of a spherical or flat forming tool. ISF is carried out regularly by a CNC machine tool or by a Robot, which follows a tool-path generated by CAM programs, without the need for costly dies. Despite research progresses in understanding the deformation mechanism in ISF the process still needs a further optimization to guarantee the reliability required for industrial applications. This paper deals with the design of a new smart forming tool, applying FEM modeling and simulation, which is able to measure one of the key process parameters: the sheet thickness during the forming process. The authors analyze the possibility to use a Hall-effect sensor integrated into the forming tool for more precise on-line thickness measurement than what can be found in the literature and first results are reported.