A Numerical Investigation to Compare Point Cloud and STL-Based Toolpath Strategies for 5-Axis Incremental Sheet Forming

To address the difficulties faced by the existing 3-axis incremental sheet forming (ISF) processes, toolpaths of 5-axis incremental sheet forming were developed to form the components with features having forming angles greater than 90°. This paper compares the STL and point cloud-based methodologies for the toolpaths generated for 5 axes incremental sheet forming. The STL models are used in the existing 5-axis toolpath techniques to determine the point normal at a contact point and hence the tool posture angles. However, there are several drawbacks associated with this approach of using STL models. Thus, a point cloud-based posture calculation strategy is proposed in this work. It was observed that the proposed approach performs better than the STL-based strategy in terms of computing efficiency. Numerical simulations were performed to validate the approach utilizing the toolpaths generated by both strategies. The simulation of the ISF process was performed to determine the feasibility of the 5-axis incremental sheet forming toolpath. Finite element simulations were performed using the shell elements for the geometry with the curvature of the wall greater than 90°. Results based on geometrical accuracy are compared to understand the differences between the two strategies.