Modeling of Deformable Thin Parts for Their Manipulation

A systematic approach to modeling of deformable soft parts for their manipulation is presented. Various deformable parts such as cords, leather products, and sheet metals are manipulated and are handled in a lot of manufacturing processes. Deformation of these parts is often utilized in order to manipulate them successfully while the manipulation sometimes fails because of unexpected deformation of the parts. Modeling of deformable objects is thus required so that the shape of the soft parts can be analyzed and can be evaluated on a computer. In this paper, we will develop an analytical method to model the shape of a deformable object. Especially, we deal with deformation of a bendable thin object. Firstly, the process of manipulating a deformable object is analyzed with regard to how the object interacts with other objects around it. Secondly, model of a bendable thin object is formulated according to a principle that the potential energy of the object reaches to the minimum at its stable shape. Thirdly, algorithm to compute the deformed shape of the object is developed by applying a nonlinear programming technique. This algorithm is applied to some examples to show how it works. Finally, a simple experiment is done to demonstrate the validity of the modeling method proposed in this paper.