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In this paper, we have proposed the modeling of cloth that realizes force together with shape to manipulate the virtual cloth. Researchers, in the community of computer graphics, have simulated only the realistic shape of cloth. However, it is also important to display the force generated from cloth for the environment where user manipulates the cloth with visual and haptic feedback. Inclusion of force with shape requires to simulate shape and force, based on the relation between them. The real relationship between shape and force can be measured by special device called "Kawabata Evaluation System(KES)". However, a cloth has hysteretic property, and relation between shape and force depends on the history of manipulation. KES data only describes incomplete unilateral relations between force and shape under specific histories of manipulation. Although there exists some previous work that simulates the shape of the cloth based on KES data, it is insufficient to simulate both shape and force considering their hysteretic relation. This paper discusses how to model a virtual cloth to simulate shape and force with realities by interpolating empirical data obtained from KES, considering their limitation due to the hysteresis. IntroductionIn the field of computer graphics, it has widely been studied how to simulate realistic shape of clothes. Clothes have many degrees of freedom, and change their shape very flexibly. Most of the previous work employs mass-spring model, which is formed by triangular or rectangular meshes of particles with mass connected by springs, and simulate rectangular-shaped clothes including flag and tablecloth [3,7] or complex garments and dresses [9,10]. More comprehensive survey of cloth modeling and its application is given in [5].Those previous work[1-4,7-10] focuses on simulating the shape of a cloth. However, in order to realize an environment for virtual cloth manipulation with both haptic and visual feedback to the user, we need to simulate force generated from the cloth as well as shape. In this paper, we discuss how to model a cloth that can realize its shape with force.In order to simulate realistic shape and force of a cloth, we have to consider three kinds of realities: (a) reality of shape, (b) reality of force, and (c) reality of the relation between shape and force. Since the previous work [3,7,10] employs mass-spring model, the force applying to each particle in the mesh is of course simulated. However, this force is not the same force generated in the real cloth but an imaginary force to achieve a realistic shape by the mass-spring model. Since real clothes have properties in between a sheet of paper and a rubber membrane, the force acting on the cloth is different from what is given by springs. In that sense, the previous work only achieves reality (a) but does not consider the reality (b) nor (c).The relation between force and shape of a cloth in stretch, bend, shear, and so forth can be obtained by a special device called "Kawabata Evaluation System (KES)" [6]. For example, fo...