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A robot or robot system is regarded as a general-purpose machine system that, like a human, can perform many tasks under conditions un-known a priori. In this paper, it was shown that a robot hand to handle pieces of cloth was manufactured for trial and plural functions of the hand was studied experimentally. The results obtained were as follows.(1) The robot hand was able to separate a piece of cloth (about 0.5mm in thickness) from a stack of pieces of cloth. (2) The output signal from the strain gauge of the hand considered to be nearly in proportion to the thickness of pieces of cloth (0.1mm N 3.0mm in thickness, under a pressure of 2.5N/cm2) held by the hand and by the signal, it was possible to distinguish thickness of the pieces of cloth.(3) The tension of a piece of cloth could be controlled between 0.09 N 0.12N by the arm and the hand.

We developed a three-dimensional apparel CAD system which simulated sample making and draping processes. In this paper, we explain the sample making system. Using this system, we can predict the shape of garment without actually making and fitting it. The basic idea for the system is that the natural shapes of garments are determined by four main factors, namely, mechanical properties of material fabrics, geometrical and topological shapes of paper patterns, shape of the human body and the way of dressing. The predicted shape of a garment changes according to these four factors. For example, there is some difference between the same pattern worn by different persons. Here we focus on the mechanical formulation of paper patterns and garments. To formulate them, we use the finite difference energy method which is one of the finite element discretization procedures. In terms of structure analysis, to predict the shape of garments is a large deformation and contact problem. To solve the large deformation problem, total Lagrangian formulation is employed in which 2nd Piola-Kirchhoff stress and Green-Lagrange strain are used. As for the contact problem, the existence of the human body is interpreted as a constraint condition. So, we describe the formulation of body surface. Finally we give some examples to show that this system is applicable to a wide range of garments.

Apparel CAD systems used now in many apparel makers consist of grading, marking and plane pattern making. These systems are limited in two-dimensional data-processing. We call the apparel CAD systems which can directly treat three-dimensional information as the second generation. For example, draping and sample making processes are the targets of it.We developed a CAD system which can simulate the sample making process. Using this system, we can estimate the shape of garment without making and dressing it actually. The basic idea for the system is that the natural shape of garment is determined by four main factors, namely, mechanical properties of material fabrics, geometrical and topological shape of paper pattern, shape of the human body and the way of dressing.In this paper, we focus the mechanical model of the fabrics and describe the formulation of it. It is based on the large deformation theory of continuous plates, while some assumptions and modifications added there are adopted from the theory of textile fabrics.Next, we describe a method of numerical analysis to treat the actual problem. The method proposed here is a modified finite element method which is practicable to deal with the textile fabrics.The following points are remarkable features of the problem. 1) Textile fabrics show anisotropic mechanical properties.2) This is a large deformation and nonlinear problem.3) Initial three-dimensional shape, in the state of unloaded and nonstrained, is not given. We can only know the shape of patterns on the plane. 4) The existence of the human body as a constraint condition is essential. 5) The requirement of accuracy in solution is not so intense. Considering these features, we developed an iterating algorithm which has a global convergency. Finally, we compare the solutions from the approximate and the strict methods in the cases of heart loop and pear loop.

As we have explained in the previous paper, we have already proposed a theory and a method to solve the mechanical behaviour of the textile fabrics. The aim of this study is to compare the results from the method above with experimental ones.Before this, it is necessary to clarify the measurement method of the mechanical properties of material fabrics. We first describe the relation between the theoretical elastic modulus and the experimental ones.In the theory, we assume that the elastic modulus of fabric is an unigue constant, but the results of the measurements are histerisis curves in general. Which part of the curve is proper to use to obtain the elastic modulus, especially in the bending case? Two values are nominated and examined through the simulations.Next, we introduce the formulation of the wall as the constraint condition. Evidently when a wall contacts to the cloth such as the heart loop, the shape of the loop changes. For this is analogous to the garment on the human body, the formulation of the wall is essential to the estimating problem.To test the applicability of the estimating method, we selected three kinds of fabric samples and prepare two kinds of walls , horizontal and sloped ones, and recorded the actual shapes of the loops in contact with the walls.We also assume that there is no friction between the fabric and the wall. The difference between the results of the simulation and the experiment occurs in the case of the sloped wall.