Abstract

The objective of the research reported here is to develop a virtual fabric handling experience using a haptic display. Development of the capability for haptic simulation of fabric hand requires a feedback system to translate fabric property data into a virtual haptic display. First of all we are establishing the representative force profile for a fabric and develop a touch feedback system capable of accurately simulating the amplitude and frequencies required. The Kawabata KES-F system provides the basis for these force profiles. The reactive forces on the fingers and hand associated with feeling a fabric are duplicated using highly sensitive touch response transducers. The user of this device will be able to evaluate fabrics in a virtual sense. Ultimately such a device could be coupled with a web-based system to allow consumers to make a hand evaluation of fabric before making purchase decisions on garments. In this paper I would mainly focus on the Haptic Simulation of Fabric Hand, which is an upcoming application of the fabric objective management technology.

Introduction

Fabric Hand

Fabric hand refers to the total sensations experienced when a fabric is touched or manipulated in the fingers. Term "fabric handle" or simply "handle" or "hand" is also used. It is a complex parameter and is related to the fabric properties such as flexibility, compressibility, elasticity, resilience, density, surface contour (roughness, smoothness), surface friction and thermal character.

Factors Affecting On Fabric Hand

In textiles raw material, yarn structure, planar structure and finishing treatments affect the fabric hand. Yarn is composed of fibres and they are either staple or filament length. All natural fibres except silk are staple length fibres. Silk and manmade fibres may be staple or filament length. Fiber size is usually specified in terms of diameter or linear density. The finer the fibres the smoother and more flexible is the yarn and the fabric will drape beautifully. Also the fiber length affects to the smoothness of the yarn. The longer the fiber and the smaller the fiber length distribution, the smoother is the spun yarn. The cross-sectional shape of the fiber affects to the smoothness of the yarn, too.

Filament yarns composed of one filament are called monofilament yarns and those with many filaments are called multifilament yarns. For apparel fabrics multifilament yarns are usually used. Comparing multifilament yarns of the same size and fiber composition, yarns containing more filaments (finer) are much less stiff than multifilament yarns containing less filaments (coarser). Flat multifilament yarns are yarns in which the filaments are straight and well aligned with the yarn axis. They tend to be the smoothest of all types of yarns. Textured yarn is a generic term given to the filament yarns with greater apparent volume, which is achieved through physical, chemical or heat treatments or a combination of these. The feel of textured-yarn fabrics against the skin is considerably different than that of flat-yarn fabric. Textured yarns give a fabric more pleasant hand, fabric becomes warmer and softer and it has less synthetic feeling) [1].

Properties of yarns and of fabric made from them are influenced by the degree of twist in the yarn. As the twist is inserted, the fibres or filaments come closer each other. High twist gives greater bending stiffness. In plied yarns, i.e. two or more single yarns twisted together, the stiffness is increased compared to single yarns.

In woven fabrics the weave and the yarn densities affect to the fabric hand. Variations in warp and weft densities and in warp and weft numbers have a significant effect to the hand. Feeling depends also on the weaves in woven structures (cf. terry fabric, velvet, and velveteen, corduroy, satin, twill, rib weave, plain).