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Shedding without dynamic warp loading is done by a loom using assemblies of polygonal shedding disks and disks for increasing weft density. The multiphase rotational loom allows completely new woven fabric structures to be manufactured, which until now was impossible to achieve using conventional looms. Woven fabrics can be manufactured with the use of warp and weft threads with extremely low tenacities, loose structures, and strong developed surfaces; as can grid structures and woven structures with pile loops. The possibility of utilizing unspinnable fibres, roving, and selvedges was demonstrated on a model of a multiphase rotational loom specially constructed for the tests.

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The paper aims to establish and introduce seam pucker assessment indicators and their dependence upon the fabric characteristics and parameters of a sewing machine.

Seams pucker defect is specific to garment from lightweight fabrics, therefore the investigation was performed with this kind of fabrics. The structure and friction properties of fabrics were determined. The influence of rotational frequency of the main shaft (varied from 200 till 2,300 min⁻¹) and pressing force (from 25 till 85 N) on seam pucker was analysed. The seam pucker was evaluated by characteristic of sharpness calculated as ratio of pucker height and length.

Analysis of the obtained results allows stating that pucker sharpness increases with growing rotational frequency of the main shaft and decreases, increasing pressing force. On the basis of correlation analysis, the relationship between proposed new indicator of seam pucker evaluation and parameters of sewing machine was sought. The obtained result demonstrates that in most cases the relative pucker coefficient is dependent upon rotational frequency of the main shaft: increasing rotational frequency also leads to higher pucker coefficient. The linear relationship between the pucker coefficient and pressing force was not observed.

This investigation has practical implications in the clothing and other nearly related industries. In the paper, results involved with evaluation of seam pucker are presented.

The research showed that in order to define seam pucker more comprehensive, it is necessary to evaluate not only ratio of pucker height and length, but also the quantity of puckers as well as their propagation. Considering to this, the new criterion for seam pucker evaluation was proposed.

Para-aramid fabrics see service in a great variety of applications, such as heavy weight lifting applications, penetration protective multilayer panels, etc. It is, therefore, increasingly important to understand the strain rate range at which the fabric has optimum mechanical properties. Although this is a field that has not been studied before, it is of great significance since it allows for the determination of the fabric’s layer location within the multilayered structure which offers maximum overall performance. The paper aims to discuss this issue.

Rectangular strips of PARAX 300 S8 woven para-aramid fabric underwent uniaxial tensile tests at various extension rates. The angle between two fibers at the center of each specimen was measured after the fabrics were elongated at different tensile extensions. This recovery angle was determined by visual analysis of the test video recordings after specimen unloading. Based on this, the recovery of the weaving form after unloading was also estimated for each tensile extension. A recovery degree based deformation characterization of the sections of a typical load/extension curve has been introduced.

The fabric does not appear to be strain rate sensitive for a strain rate range of 0.03 s-1 to 0.53 s-1, and its load/extension characteristics are generally not affected by the extension rate. However, break load and maximum elongation values appear reduced at actuator velocity of 2,400 mm/min and enhanced at 3,600 mm/min. Finally, the effect of extension rate on the different deformation zones of the material is reported and discussed.

The current research work offers a novel approach for the investigation of non-standard response of woven para-aramid fabrics when subjected to tensile loading under various strain rates. Additionally, a new approach is introduced to explain in detail the deformation zones based on the recovery degree of the fiber orientation angle after unloading.

The industrial robot has now become accepted in almost every sector of manufacturing industry as this review of robot applications and specifications shows.

Upper-limb joint kinematics are highly complex and the kinematics of rehabilitation exoskeletons fail to reproduce them, resulting in hyperstaticity and human–machine incompatibility. The purpose of this paper is to design and develop a compatible exoskeleton robot (Co-Exos II) to address these problems.

The configuration synthesis of Co-Exos II is completed using advanced mechanism theory. A compatible configuration is selected and four passive joints are introduced into the connecting interfaces based on optimal configuration principles. A Co-Exos II prototype with nine degrees of freedom (DOFs) is developed and still owns a compact structure and volume. A new approach is presented to compensate the vertical glenohumeral (GH) movements. Co-Exos II and the upper arm are simplified as a guide-bar mechanism at the elevating plane. The theoretical displacements of passive joints are calculated by the kinematic model of the shoulder loop. The compatible experiments are completed to measure the kinematics of passive joints.

The compatible configuration of the passive joints can effectively reduce the gravity influences of the exoskeleton device and the upper extremities. The passive joints exhibit excellent compensation effect for the GH joint movements by comparing the theoretical and measured results. Passive joints can compensate for most GH movements, especially vertical movements.

Co-Exos II possesses good human–machine compatibility and wearable comfort for the affected upper limbs. The proposed compensation method is convenient to therapists and stroke patients during the rehabilitation trainings.

Machining operations on multilayer circuit boards play the two major roles of establishing the finished geometry of the board and leading to the interconnection of the various conductor layers and it is likely that for some considerable time carbide cutting tools will continue to be used in the machining process. Fundamental and detailed considerations of the parameters influencing machining are presented prior to analysing the two predominant areas of use. Mention is made of some advanced machining techniques, involving mechanical, chemical and laser methods.

The purpose of this paper is to investigate the effect of joint clearance on the behavior of a needle driver mechanism (a slider-crank linkage) of a typical sewing machine with an imperfect joint between the coupler and the slider (including needle).

In order to model the clearance, the momentum exchange approach is used. The Lankarani and Nikravesh’s continuous contact force model is used to model the contact force, and the modified Coulomb’s friction law represents the friction between sliding members. The penetration force applied on the needle by fabric is chosen based on an experimental data in the literature. The dynamic response is validated for the existing properties in the literature without considering the penetration force.

It is shown that the clearance joint made considerable effect on the dynamic response of the system. The rough changes of the needle acceleration and jerk are obvious. The base reaction force changed roughly and did not vary as smooth as that of the mechanism with ideal joint. So, clearance joint in the mechanism could lead to an undesirable vibration in the system. Furthermore, the crank driver must provide a non-smooth moment on the crank to keep the crank rotational velocity constant. Moreover, reducing the clearance size sufficiently could make the dynamic response closer to that of the mechanism with ideal joint. In addition, smoother crank moment could be required if the clearance size is reduced sufficiently. Furthermore, the rough change of the base reaction force which can represent the vibration caused by the mechanism on the fixed frame could be reduced if the clearance size is small enough.

Lockstitch sewing machine is one of the most common apparel industrial machines. The needle driver mechanism of a sewing machine could have an important role for proper stitch forming. On the other hand, clearances are inevitable in assemblage of mechanisms to allow the relative motion between the members. This clearance is due to machining tolerances, wear, material deformations, and imperfections, and it can worsen mechanism performance such as precision, dynamic behavior and vibration. Unfortunately, despite the importance of the dynamic behavior of the needle driver mechanism from practical point of view, very little publications have focused especially on the investigation of the effect of clearance joint on the dynamic behavior of the sewing machine which could lead to undesired vibration of the system and shorter lifetime as a result. In this paper, the dynamic behavior of the system including, needle velocity and acceleration, crank moment and base reaction force was compared with that of the ideal mechanism. Finally, the effect of clearance size on the dynamic behavior of the system was investigated.

THE enlarged scale and more varied content of this year's Business Efficiency Exhibition recalls the importance of the office in modern business. So, too, do those vast, austere rectangular boxes whose modular construction makes them so depressingly alike. Those in London and other major cities can be matched exactly in Frankfurt or Brussels, Milan or Montreal. This is a natural consequence of the tendency for the number of manual workers to decline and of clerical ones to increase.

IT would be quite refreshing to have an open breeze blowing through the ranks of work study technicians these days. Away with the ponderous exponents of the mystic art and, instead, finding the experts telling the workers how easy work study really is if only you sit down and think about it. It has, of course, many difficult and complex aspects but let us not confuse the issue, since these aspects can be left to the professionals' — after all that is what they get paid for — sorting out and providing solutions to the problems!