Robotic Metal Spinning − Forming Non-axisymmetric Products Using Force Control −

Metal spinning is a plastic forming process that forms a metal sheet by forcing the metal onto a rotating mandrel using a roller tool. Products formed by metal spinning have been inherently limited to round shapes. In this paper, we propose metal spinning of non-axisymmetric products by applying hybrid position/force control. The pushing force of the roller is regulated so that the roller can track the changing radius of the mandrel. Our forming experiment demonstrates that a thin aluminum sheet can be formed into a non-axisymmetric shape.

I. Introduction

Metal spinning [1] is a plastic forming process that forms a metal sheet or tube by forcing the metal onto a rotating mandrel using a roller or a paddle tool (Fig. 1). It is widely used for producing round hollow metal parts and products. This forming process is suitable for limited production lots of a wide variety and it is particularly effective in prototyping and product development, since it needs only one mandrel which costs much less than dies for metal stamping or deep drawing. Besides the use of numerically controlled spinning machines, metal spinning is also performed manually by artisans and is known as a highly skilled manufacturing handicraft that requires decades of experience.