Improving feeding efficiency of a sewing machine by on-line control of the presser foot

This paper presents a contribution towards the development of a new generation of sewing equipment integrating auxiliary add-on kits to improve performance and flexibility in the production of high-quality garments. An overview of all the recent developments concerning the redesign of the first PC-based controller developed for a novel electromagnetically actuated presser foot on an industrial overlock sewing machine will be presented. Other software modules, developed to ease the establishment of control references and the tuning of the controller parameters, as well as a brief discussion and analysis of the obtained results, will also be described in this paper. According to the latest results here reported, the presser foot firmly controls the fabric plies for a wide range of materials and situations

Somatic senses required for the emotional design of upper limb prosthesis

Despite the technological advances associated with prostheses, the total embodiment is still the great challenge in the segment of assistive technology. One of the main aspects is that the bionic member’s sensibility is not responsive to the environment that surrounds it. The purpose of this study aims to identify the perceptual modalities of the somatic senses that are required for a more sensible prosthesis. The methodological strategy contemplates literary research and proposes an interrelationship between neuroscience with philosophical/cultural studies, which regards the different concepts of sensory experience. Such data were analyzed quantitatively and qualitatively. The main conclusion points out that it would be important to unite the nine physiological requirements identified in the state of the art, with the ontological image construction of the prosthesis, in order to create a sensory experience that, in addition to the perceptive organs, builds up by the visual areas of the brain.This work is financed by Project “Deus ex Machina”, NORTE-01-0145-FEDER-000026, funded by CCDRN, through Sistema de Apoio à Investigação Científica e Tecnológica (Projetos Estruturados I&D&I) of Programa Operacional Regional do Norte, from Portugal 2020 and byProject UID/CTM/00264/2019 of 2C2T –Centro de Ciência e Tecnologia Têxtil, funded by National Founds through FCT/MCTES

Fuzzy logic based control strategies for an electromagnetic actuated sewing machine presser foot

Comunicação apresentada na International Conference on Industrial Technology, Hammamet, Tunisia, 8 - 10 Dezembro 2004.Industrial sewing machines have been significantly improved in recent years and especially electronic sewing control is now being introduced. This study concerns the development of a controller for an electromagnetically actuated presser foot. The controller is responsible for controlling the vertical movement of the presser foot. This is an important point since the presser foot tends to bounce at high sewing speeds, resulting in irregular seams. In this study a fuzzy logic controller was used. The reference displacement value is set up by an adaptive method in order to respect changes on the number of plies. The tested fuzzy logic controller allows a better performance of the control especially in relation with different fabrics. During this study another control strategy was considered. This control strategy combines a PI-algorithm with a fuzzy logic controller. Yet, the controller restricts the use of new fabrics, which have not been defined in advance. This aspect will be a major point in the future development in order to recognize the fabrics during sewing and to adapt the controller adequately.(undefined

Adaptive control of an electromagnetically actuated presser-foot for industrial sewing machines

This study describes some possibilities of setting up an adaptive control method for an electromagnetically actuated presser-foot in an industrial high-speed sewing machine. The control of fabrics feeding in sewing machines is difficult not only because of the complexity of relations between the intervening variables (material properties, sewing speed), but also because in many operations a varying number of material plies are crossed. This implies that the reference for the controller has to be adapted dynamically. Several methods, using PID and/or fuzzy logic control, have been tried and are described in this paper. A preliminary sewing test is able to provide data to tune the controller variables. With these adaptation techniques, the machine would be able to automatically adapt its feeding system according to the material being sewn.Fundação para a Ciência e a Tecnologia (FCT

Microalgal reactors: a review of enclosed system designs and performances

One major challenge to industrial microalgal culturing is to devise and develop technical apparata, cultivation procedures and algal strains susceptible of undergoing substantial increases in efficiency of use of solar energy and carbon dioxide. Despite several research efforts developed to date, there is no such thing as “the best reactor system”- defined, in an absolute fashion, as the one able to achieve maximum productivity with minimum operation costs, irrespective of the biological and chemical system at stake. In fact, choice of the most suitable system is situationdependent, as both the species of alga available and the final purpose intended will play a role. The need of accurate control impairs use of open-system configurations, so current investigation has focused mostly on closed systems. In this review, several types of closed bioreactors described in the technical literature as able to support production of microalgae are comprehensively presented and duly discussed, using transport phenomenon and process engineering methodological approaches. The text is subdivided into subsections on: reactor design, which includes tubular reactors, flat plate reactors and fermenter-type reactors; and processing parameters, which include gaseous transfer, medium mixing and light requirements

Detecting abnormalities in endoscopic capsule images using color wavelet features and feed-forward neural networks

This paper presents a system to support medical diagnosis and detection of abnormal lesions by processing endoscopic images. Endoscopic images possess rich information expressed by texture. Texture information can be efficiently extracted from medium scales of the wavelet transform. The set of features proposed in this paper to encode textural information is named color wavelet covariance (CWC). CWC coefficients are based on the covariances of second order textural measures, an optimum subset of them is proposed. The proposed approach is supported by a classifier based on multilayer perceptron network for the characterization of the image regions along the video frames. The whole methodology has been applied on real data containing 6 full endoscopic exams and reached 87% specificity and 97.4% sensitivity.Center Algoritm

Avaliação da eficiência de diferentes produtos enológicos na remoção de ocratoxina A de vinho

As micotoxinas são metabolitos secundários tóxicos produzidos por certos fungos, sendo a ocratoxina A (OTA) das mais importantes. A presença de OTA nos vinhos pode constituir um risco para a saúde dos consumidores, sendo por isso aconselhado que se tomem medidas para atingir níveis seguros para o consumo humano [1]. De acordo com o Regulamento n.º 1881/2006 da Comissão Europeia, o limite máximo para a OTA em vinho é de 2 µg/kg [2]. Sendo assim, foi objetivo deste trabalho conhecer a eficiência de diferentes produtos enológicos na remoção de OTA de vinhos, bem como o seu impacto nas suas características organoléticas. Foram testados onze produtos enológicos diferentes, com origem mineral, sintética, microbiana, vegetal e animal, de forma a avaliar a sua eficiência na remoção de OTA de vinhos. Os ensaios foram realizados em vinhos artificialmente suplementados com OTA numa concentração final de 10 µg/L. O produto enológico mais eficiente na remoção de OTA do vinho branco (80%) é composto por gelatina, bentonite e carvão ativado. Reduções entre 10-30% foram também obtidas com o caseinato de potássio, paredes de células de levedura e proteína de ervilha. Com a aplicação de bentonite, carboximetilcelulose, polivinilpolipirrolidona e quitosana não se verificou nenhuma remoção considerável de OTA dos vinhos brancos. Estes resultados podem fornecer informações úteis para os produtores de vinho, ajudando-os na seleção do produto enológico mais adequado para a remoção de OTA de vinhos brancos, reduzindo a toxicidade do vinho e melhorando simultaneamente a segurança alimentar e qualidade do produto final.Agradecimentos: Este trabalho foi financiado por fundos FEDER através do Programa Operacional Factores de Competitividade - COMPETE e por fundos nacionais através da Fundação para a Ciência e a Tecnologia -FCT, ref. FCOMP-01-0124-FEDER-028029 e PTDC/AGR-TEC/3900/2012, respetivamente. Luís Abrunhosa recebeu apoio através da bolsa Incentivo/EQB/LA0023/2014 do ON.2 O Novo Norte

Typology based method for choosing old masonry walls inspection procedures

The diagnosis of historic masonry walls is an intricate and complex field and has been an object of research for many years. This paper aims to propose practical methodologies for the diagnosis of historic masonry walls, specifically based on their typological characteristics. In order to develop such procedures, information relating to historic masonry typologies in Portugal, classified as rural, urban and military was gathered and techniques for the assessment of historic masonry were studied. All information was integrated to develop a pattern typology oriented methodology. Developed methodology was tested and validated in a small diagnosis campaign carried out in the Guimarães Castle. Methodology was proven to be advantageous and although the study is limited and focused on the Portuguese architectural specificities, it still holds global classifications, and therefore can be useful for any diagnosis procedure of a historic masonry wall

Estudos geológicos aplicados à indústria extractiva de mármores no Anticlinal de Estremoz : o caso do Núcleo de Pardais

O Anticlinal de Estremoz é um dos principais centros mundiais produtores de mármores para fins ornamentais, no qual estão legalmente definidas unidades de ordenamento afectas a esta actividade. Para poder continuar nesta posição privilegiada, tem sido objecto de estudos que visam melhorar a sua caracterização e permitir adaptar a sua exploração às crescentes exigências de eficácia ambiental e económica. Neste trabalho, apresentam-se alguns estudos de carácter geológico que envolveram cartografia litoestrutural, levantamentos de fracturação e realização de sondagens que tiveram como objectivo contribuir para o ordenamento da actividade extractiva da unidade UNOR 5 - Pardais. Foi elaborada uma Carta de Risco Geoeconómico para esta UNOR que pretende classificá-la em função da sua maior ou menor aptidão para a produção de mármore ornamental

Classification of endoscopic capsule images by using color wavelet features, higher order statistics and radial basis functions

This paper presents a system to support medical diagnosis and detection of abnormal lesions by processing capsule endoscopic images. Endoscopic images possess rich information expressed by texture. Texture information can be efficiently extracted from medium scales of the wavelet transform. The set of features proposed in this paper to code textural information is named color wavelet covariance (CWC). CWC coefficients are based on the covariances of second order textural measures, an optimum subset of them is proposed. Third and forth order moments are added to cope with distributions that tend to become non-Gaussian, especially in some pathological cases. The proposed approach is supported by a classifier based on radial basis functions procedure for the characterization of the image regions along the video frames. The whole methodology has been applied on real data containing 6 full endoscopic exams and reached 95% specificity and 93% sensitivity.Centre Algoritm