Iterative process control and sensor evaluation for deep drawing tools with integrated piezoelectric actuators

Abstract

Due to the design-driven increase in complexity of forming car body parts, it becomes more difficult to ensure a stable forming process. Piezoelectric actuators can influence the material flow of stamping parts effectively. In this article the implementation of piezoelectric actuators in a large scale sheet metal forming tool of a car manufacturer is described. Additionally, it is shown that part quality can be assessed with the help of triangulation laser sensors, which are mounted on the blankholder. The resulting flange draw-in signals were processed and used to adopt the applying actuator force iteratively to reduce the occurrence of cracks. It was shown that process control helped to improve the quality of the stamping parts significantly.