Dubravko Rogale

Systematic Representation and Application of a 3D computer-Aided Garment Construction Method, Part I 3D garment basic cut construction on a virtual body model

Purpose – To establish a method of transforming the 3D cutting patterns constructed and modelled into 2D patterns, excluding the fabric parameters.Design/methodology/approach – Three methods have been developed for transforming 3D cutting part segments into 2D segments. They are based on the computer‐based application of the mathematical models developed. The mathematical models differ in their concepts and the application in a particular manner of transforming the 3D segments. Complex spatial matrix transformations have also been developed and used to further transform the 2D segments into the plane of chained 2D cutting pattern segments.Findings – Two‐dimensional cutting patterns have been defined for the 3D garment model, initially constructed on a computer‐generated body model.Research limitations/implications – The method has been developed on an example of a 3D garment basic cut construction of a single article of clothing. However, the same principles can be applied and developed for any garment ba...

Systematic representation and application of a 3D computer‐aided garment construction method: Part II: spatial transformation of 3D garment cut segments

Purpose – To establish a method of transforming the 3D cutting patterns constructed and modelled into 2D patterns, excluding the fabric parameters. Design/methodology/approach – Three methods have been developed for transforming 3D cutting part segments into 2D segments. They are based on the computer‐based application of the mathematical models developed. The mathematical models differ in their concepts and the application in a particular manner of transforming the 3D segments. Complex spatial matrix transformations have also been developed and used to further transform the 2D segments into the plane of chained 2D cutting pattern segments. Findings – Two‐dimensional cutting patterns have been defined for the 3D garment model, initially constructed on a computer‐generated body model. Research limitations/implications – The method has been developed on an example of a 3D garment basic cut construction of a single article of clothing. However, the same principles can be applied and developed for any garment basic cut. Practical implications – The mathematical models developed can be used in a new computer‐based application for the 3D garment construction and the development of the 2D cutting patterns, matched to individual physical characteristics. Originality/value – The most outstanding property of the method developed is the possibility of gradual transformation of 3D cuts into 2D ones, with no need to define physical‐mechanical properties of the fabric used and no need to introduce fabric drape. The newly created 2D cutting patterns are of outstanding quality and preciseness.

Investigation of the strength of ultrasonically welded sails

Purpose – Today when the newest high‐tech fibers and sophisticated material constructions are used for the production of sails, forming 3D sail shape from 2D sailcloth has still remained very primitive because classic sewing techniques are mostly used. Since, the clothing and technical textile industry has been recently using some of contemporary joining techniques (ultrasonic, thermal, high‐frequency) replacing classic sewing, this paper seeks to investigate the possibility of ultrasonic welding in the production of sails, and the strength of obtained bonds.Design/methodology/approach – Concerning the aim, sails were made employing the classic and modern (ultrasonic) joining technique whereby bonding parameters such as amplitude and welding speed, geometry of anvil wheels were varied. Objective quality evaluation of the bond made in such a way, was performed in order to be more exact about its strength.Findings – Based on the obtained results it has been concluded that ultrasonic welding may successfully...

Croatian anthropometric system meeting the European Union

Purpose – Anthropometry as one of anthropology methods is concerned with the measurement of the human body and determining the relationship of the size and proportions of the human body. Aims to outline the main features of the Croatian anthropometric system (HAS).Design/methodology/approach – The paper provides a description of the major characteristics included in HAS, the STIRP project supported by the Ministry of Science, Education and Sports by means of the HITRA program.Findings – In its TEST subprogram, HAS includes the first systematic anthropometric measurement in all Croatian counties and in the city of Zagreb. The objective of HAS is to determine a proposal of the new size system of clothing and footwear. The paper describes major characteristics included: anthropometric measurements and target points, part of practical measurements, survey of measurements based on age groups and instruments used for these purposes, notes about field measurements and HAS users.Practical implications – The imple...

Methods of automatic computerised cutting pattern construction

The procedure of computerised automatic construction of a cutting pattern for men’s shirt is presented. It is based on the calculation of construction measures necessary for the calculation of all the construction elements. The procedure of construction is similar to the conventional hand procedure, but is done using a computer, so that the locations of the co‐ordinates of all the principal and auxiliary points on cutting part contours are calculated. Straight segments are drawn afterwards through these calculated points and curved segments interpolated.

Portable computer measuring systems for automatic process parameter acquisition in garment sewing processes

A measuring system for automatic process parameter acquisition in garment sewing operations has been presented. The measuring equipment is based upon the usage of a very powerful portable notebook IBM compatible personal computer, equipped with an AD converter, measuring instruments and adequate software packages for data storing and analysis. Characteristics of measuring instruments and sensors have also been given, together with measuring process description, all connected with two independent video‐camera systems, working in two planes, used for working operation analysis at workplaces in garment sewing operations.

Garment sewing processing parameters: determination using numerical methods and computers

Presents the possibility of determining increased numbers of processing parameters for garment sewing using numerical methods and computers. The determination of new parameters has been made possible by employing equipment designed to measure stitching speed and to store the data in a computer as a function of time. Mathematical operations of searching and calculating, and numerical methods of derivation or integration can be applied to the measured pairs of data concerning the stitching speed and time period. In this way, the values of new processing parameters can be obtained, or their function flows investigated.

Investigation of operative logical movement groups in garment sewing

The development of the equipment for investigating operative logical movement groups in garment production is presented. The characteristics of the equipment and software packages used are described, as well as the processing of the video recordings, from recording at the workplace, marker separation to marker system chain‐linking, which, as a final result, are used in the course of logical movement group defining.

Numerical simulation of textile flexibility testing

A non‐linear numerical simulation of a standard procedure for textile flexibility testing is performed using discretised beam bending model. Geometric non‐linearity due to large deflections is traced using incremental method. Linear moment‐curvature response is assumed, as well as constant curvature of a finite element of the beam. Numerical procedure is incorporated into a PC programme producing graphical results for the deformed shape of the specimen, non‐linear load‐deflection diagrams and internal force distributions in deformed state. Finally, the method is applied to compute the flexural stiffness of textile materials from the data produced by the standard procedure for flexibility testing.

Technical systems in intelligent clothing with active thermal protection

Purpose – This paper seeks to examine the practical construction of a patented intelligent article of clothing with active thermal protection, outer shell with a variable thickness, system of thermoinsulating chambers, sensors and measuring systems, microcontroller and control system, actuator system and power supply system based on hardware aspect.Design/methodology/approach – Based on practical construction and software aspect, a measuring and control program with algorithm of intelligent behavior is presented.Findings – An intelligent article of clothing with thermal protection like a complex technical system consisting of a very complex architecture connected by different bus types to constitute a complex system acting synchronously and effectively controlled by the microcontroller containing the program which is based on the algorithm of the intelligent behavior.Research limitations/implications – The technical systems described represent a suitable basis for experiments and scientific research durin...