Development of a flattening system for sheet metal with free-form surface

In order to improve the flattening quality of sheet metal with free-form surface, a flattening system was developed. The system framework was proposed and the key technologies such as mesh quality measuring criterion, center triangle indexing algorithm, coordinate transforming principle, and initial flattening method were elaborated. Moreover, a planar spring-mass model was presented to optimize the initial flattening result, and the flowchart of the proposed flattening method was designed. Finally, three simulation examples were carried out and the comparison results indicated that the proposed system was proved feasible and efficient.