This study deals with a robot manipulator for yarn bobbin handling in the cotton yarns lattice distortion modification system.The aim is to achieve an operation of yarn bobbin handling with minimal execution time,ener...This study deals with a robot manipulator for yarn bobbin handling in the cotton yarns lattice distortion modification system.The aim is to achieve an operation of yarn bobbin handling with minimal execution time,energy consumption and jerk in motion together.The placement of the robot,in relation to the yarn bobbin stations,is also optimized in conjunction of trajectory optimization.Three possible techniques for building the handling traj'ectory were considered:the quaternion spherical linear interpolation in Cartesian space,the quintic polynomial spline and quintic B-spline in joint space.The genetic algorithm(GA) was used to optimize the trajectories of the robot,with a penalty function to handle nonlinear constraints associated in the robot motion.Two simulations of the optimal trajectory in joint space and the placement of robot were carried out and the results obtained were presented and discussed.It is concluded that the quintic polynomial spline constructs a better trajectory in joint space and the proper placement of robot makes better performance.展开更多
Generally, ring spun yarns are manufactured from roving which is produced by roving frame. In this paper, an experiment has been done producing ring spun cotton yarn directly from finisher drawn sliver eliminatin...Generally, ring spun yarns are manufactured from roving which is produced by roving frame. In this paper, an experiment has been done producing ring spun cotton yarn directly from finisher drawn sliver eliminating the roving frame. Total 3 types of yarn with the various linear density of 8 Ne, 10 Ne & 12 Ne were produced using a roving frame and without using a roving frame. In the next step, physical and mechanical properties of those yarns including unevenness, imperfections, hairiness & tenacity were investigated. The result showed that ring spun cotton yarns produced from sliver exhibited inferior physical and mechanical properties compared with samples from the conventional ring spinning system.展开更多
Nowadays,more and more natural or functional fibers are being investigated due to their utilization in thermal underwear.Kapok fiber is one of the natural cellulosic fibers whose source is the kapok plant. It has holl...Nowadays,more and more natural or functional fibers are being investigated due to their utilization in thermal underwear.Kapok fiber is one of the natural cellulosic fibers whose source is the kapok plant. It has hollow body and sealed tail,which exhibits desirable features required for functional textiles of this nature. In this study,cotton / kapok( 80 /20 by mass) blended yarn with two types of yarn size 18. 5 and 14. 8 tex,respectively are knitted into plain stitches. The fabrics are undergone with an optimal preparation plan according to orthogonal design. Then,after dyeing and softening,fabric properties including thermal and water-vapour resistances, wicking property, pilling behaviour, and surface morphology,are tested and scrutinized for their candidacy for thermal underwear. The results showed that cotton / kapok blended fabrics have good thermal resistance which is significantly higher than those of cotton / modal blended fabrics,and the same water vapour resistance compared with cotton / modal blended fabrics which are normally used as underwear. Cotton / modal blended knitted fabrics has better pilling grade than cotton / kapok blended fabrics. Meanwhile, the cotton / kapok blends fabrics have good wicking property. Collectively,it was concluded that cotton / kapok blended fabric was appropriate for thermal underwear. However,the main limitation of these fabrics is their pilling properties.展开更多
Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to...Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to a cotton spinning sector and influence its quality.Those two properties can change the entire spinning process.Understanding this,moisture and temperature must be kept under control when used during the spinning process,once the environment is hot and dry,the cotton yarns absorb moisture and lose the minimal consistency.According to this information,this paper was developed testing four types of cotton yarns,one kind of cotton from Brazil and the others from Egypt.The yarns were exposed to different temperatures and moisture in five different tests and in each test,six samples were examined through physical and mechanical tests:resistance,strength,tenacity,yarn’s hairness,yarn’s evenness and yarn’s twisting.All the analyses were accomplished at Laboratório de Mecânica dos Fluidos and at COATS Corrente S.A.,where,it was possible to use the equipments which were fundamental to develop this paper,such as the STATIMAT ME that measures strength,tenacity,Zweigler G566 that measure hairiness in the yarn,a skein machine and a twisting machine.The analysis revealed alterations in the yarn’s characteristics in a direct way,for example,as moisture and temperature were increased,the yarn’s strength,tenacity and hairness were increased as well.Having the results of all analysis,it is possible to say that with a relatively low temperature and a high humidity,cotton yarns have the best performance.展开更多
According to the Statistics Center of China National Textile and Apparel Council,inthe first four months of2010,the import of cotton yarn achieved 103085 tons,with
The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplish...The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplished mainly in terms of a spot-check on semi-product and a succedent adjust in process parameters during spinning based on technicians' experience.However,it is theoretically believed among manufacturers that with fixed technical levels and parameters in the spinning process,the quality parameters of assorted cotton have a certain influence on the CV.In order to find out a rule of the influence that assorted cotton has on the CV,a GM(1,N)model,correlated raw cotton's quality parameter with the CV,has firstly been developed according to the modeling theory of grey system,and then been applied in the designing step to predict the CV.It has been approved by practical modeling and validation that the model could fit preferably an accrual CV value,and provide a method of quantitative predicting analysis for textile manufacturers to design cotton yarn's quality.展开更多
基金National Key Technology Support Program,China(No.2012BAF13B03)Program for Changjiang Scholars and Innovative Research Team in University,China(No.IRT1220)
文摘This study deals with a robot manipulator for yarn bobbin handling in the cotton yarns lattice distortion modification system.The aim is to achieve an operation of yarn bobbin handling with minimal execution time,energy consumption and jerk in motion together.The placement of the robot,in relation to the yarn bobbin stations,is also optimized in conjunction of trajectory optimization.Three possible techniques for building the handling traj'ectory were considered:the quaternion spherical linear interpolation in Cartesian space,the quintic polynomial spline and quintic B-spline in joint space.The genetic algorithm(GA) was used to optimize the trajectories of the robot,with a penalty function to handle nonlinear constraints associated in the robot motion.Two simulations of the optimal trajectory in joint space and the placement of robot were carried out and the results obtained were presented and discussed.It is concluded that the quintic polynomial spline constructs a better trajectory in joint space and the proper placement of robot makes better performance.
文摘Generally, ring spun yarns are manufactured from roving which is produced by roving frame. In this paper, an experiment has been done producing ring spun cotton yarn directly from finisher drawn sliver eliminating the roving frame. Total 3 types of yarn with the various linear density of 8 Ne, 10 Ne & 12 Ne were produced using a roving frame and without using a roving frame. In the next step, physical and mechanical properties of those yarns including unevenness, imperfections, hairiness & tenacity were investigated. The result showed that ring spun cotton yarns produced from sliver exhibited inferior physical and mechanical properties compared with samples from the conventional ring spinning system.
基金Technical Standards for the Development of Kinitted Jinlong Underw ear Factory of Guangdong Province,China(No.HX201303000008)
文摘Nowadays,more and more natural or functional fibers are being investigated due to their utilization in thermal underwear.Kapok fiber is one of the natural cellulosic fibers whose source is the kapok plant. It has hollow body and sealed tail,which exhibits desirable features required for functional textiles of this nature. In this study,cotton / kapok( 80 /20 by mass) blended yarn with two types of yarn size 18. 5 and 14. 8 tex,respectively are knitted into plain stitches. The fabrics are undergone with an optimal preparation plan according to orthogonal design. Then,after dyeing and softening,fabric properties including thermal and water-vapour resistances, wicking property, pilling behaviour, and surface morphology,are tested and scrutinized for their candidacy for thermal underwear. The results showed that cotton / kapok blended fabrics have good thermal resistance which is significantly higher than those of cotton / modal blended fabrics,and the same water vapour resistance compared with cotton / modal blended fabrics which are normally used as underwear. Cotton / modal blended knitted fabrics has better pilling grade than cotton / kapok blended fabrics. Meanwhile, the cotton / kapok blends fabrics have good wicking property. Collectively,it was concluded that cotton / kapok blended fabric was appropriate for thermal underwear. However,the main limitation of these fabrics is their pilling properties.
文摘Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to a cotton spinning sector and influence its quality.Those two properties can change the entire spinning process.Understanding this,moisture and temperature must be kept under control when used during the spinning process,once the environment is hot and dry,the cotton yarns absorb moisture and lose the minimal consistency.According to this information,this paper was developed testing four types of cotton yarns,one kind of cotton from Brazil and the others from Egypt.The yarns were exposed to different temperatures and moisture in five different tests and in each test,six samples were examined through physical and mechanical tests:resistance,strength,tenacity,yarn’s hairness,yarn’s evenness and yarn’s twisting.All the analyses were accomplished at Laboratório de Mecânica dos Fluidos and at COATS Corrente S.A.,where,it was possible to use the equipments which were fundamental to develop this paper,such as the STATIMAT ME that measures strength,tenacity,Zweigler G566 that measure hairiness in the yarn,a skein machine and a twisting machine.The analysis revealed alterations in the yarn’s characteristics in a direct way,for example,as moisture and temperature were increased,the yarn’s strength,tenacity and hairness were increased as well.Having the results of all analysis,it is possible to say that with a relatively low temperature and a high humidity,cotton yarns have the best performance.
文摘According to the Statistics Center of China National Textile and Apparel Council,inthe first four months of2010,the import of cotton yarn achieved 103085 tons,with
基金Hunan Provincial Basic Science Foundation of China(No.2007FJ3046)Key Scientific Research Fundof Hunan Provincial Education Department,China(No.07A048)
文摘The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplished mainly in terms of a spot-check on semi-product and a succedent adjust in process parameters during spinning based on technicians' experience.However,it is theoretically believed among manufacturers that with fixed technical levels and parameters in the spinning process,the quality parameters of assorted cotton have a certain influence on the CV.In order to find out a rule of the influence that assorted cotton has on the CV,a GM(1,N)model,correlated raw cotton's quality parameter with the CV,has firstly been developed according to the modeling theory of grey system,and then been applied in the designing step to predict the CV.It has been approved by practical modeling and validation that the model could fit preferably an accrual CV value,and provide a method of quantitative predicting analysis for textile manufacturers to design cotton yarn's quality.
