Incremental sheet forming (ISF) offers great flexibility in producing complex sheet parts as compared with conventional sheet forming processes where part-specific die sets are required to form a product. While there are many potential applications of ISF in various industries, toolpath planning for multifeature parts remains a leading challenge hindering the wide adoption of ISF. In this study, a criterion based on the gradient of the target surface was established for determining the appropriate feature forming sequence. Based on the analysis of the gradients of the surface, multifeature geometries were separated into two categories: “plane-referenced” and “surface-referenced.” Experimental investigations of forming a multifeature air intake as an example were carried out to demonstrate the proposed criterion and feature forming sequence. The results show that the choice of the optimal sequence depends on the type of geometry formed. The proposed criterion extends existing toolpath strategies for relatively regular geometries, where features are formed from flat or inclined bases to more complex geometries with features on a curved basis. This work will be of interest to both design and manufacturing communities.
