A geometric model of relaxed plain-nitted fabric isproposed.A method based on the model for predictingthe loop length from the course spacing,wale spacing offabric and the diameter of yarn is deduced,as well as a comp...A geometric model of relaxed plain-nitted fabric isproposed.A method based on the model for predictingthe loop length from the course spacing,wale spacing offabric and the diameter of yarn is deduced,as well as a computer program is developed to graphically represent the structures of plain knitted fabric with various struc-tural parameters.展开更多
Weft knitted fancy fabrics are widely used in knitted garment design. Due to the complexity of the structures, their modeling and simulation needs to be solved in three-dimensional (3D) CAD developments. In this paper...Weft knitted fancy fabrics are widely used in knitted garment design. Due to the complexity of the structures, their modeling and simulation needs to be solved in three-dimensional (3D) CAD developments. In this paper, 3D loop geometrical models of weft knitted fancy structures, including tuck stitch, jacquard stitch, transfer stitch and fleecy stitch, were developed based on an improved model of plain loop, and their central axes as some 3D space curves were achieved by using Non-Uniform Rational B-Splines (NURBS). The 3D visual simulation programme was written in C++ programming language using OpenGL, which was a function library of 3D graphics. Some examples of weft knitted fancy fabrics were generated and practical application of 3D simulation was discussed.展开更多
Based on classic theory of elastic rod,the warp-knitted loop geometry in plane is independent of yarn properties,while there is a certain gap between the geometrical model and the actual fabrics.According to this prob...Based on classic theory of elastic rod,the warp-knitted loop geometry in plane is independent of yarn properties,while there is a certain gap between the geometrical model and the actual fabrics.According to this problem,further analysis of loop geometry is done based on the theory of elastic rod with theoretical calculation and experiments.The theoretical analysis found that the distance between the contacted points at the loop root affected the loop geometry,and the distance was affected by the ratio of bending rigidity and the friction between yarns.The experiments,forming simple loop by taking the yarn as an elastic rod,found that the bending rigidity affected the loop geometry.Then the relationships between warp-knitted loop geometry in plane of metallic fabrics and wires properties were studied.The results show that metallic fabrics are more suitable for the theory of elastic rod;the friction and bending rigidity of wire yarns affect the loop geometry in plane.Also,the elongation of yarn affects the loop geometry in the actual warp-knitted fabric.展开更多
In this paper,the relations between the parameters of stitch structure and the needle penetra-tion force,and the method by using the needle penetration force detected to evaluate the looplength and evenness of knitted...In this paper,the relations between the parameters of stitch structure and the needle penetra-tion force,and the method by using the needle penetration force detected to evaluate the looplength and evenness of knitted fabric indirectly are analysed and discussed.A microcomputer system with a needle sensor and author’s program are used as a pick up setcombined with a data analysis system,for sampling and analysing the needle penetration forcedata.A lot of experimental research work has been done for knitted fabric of some kinds of knittedstitch and loop length.As a summary of this study,some conclusions can be drawn from the linearregression between the needle penetration force and the loop length.Then,the size and evenness ofthe loop length of knitted fabric can be indicated indirectly by detecting the value and variance ofneedle penetration force.It offers an effective method to detect and evaluate the evenness of knit-ted fabric with an efficiently high speed.展开更多
文摘A geometric model of relaxed plain-nitted fabric isproposed.A method based on the model for predictingthe loop length from the course spacing,wale spacing offabric and the diameter of yarn is deduced,as well as a computer program is developed to graphically represent the structures of plain knitted fabric with various struc-tural parameters.
基金Natural Science Foundation of Tianjin,China( No. 11JCYBJC26400) Tianjin High School Scientific and Technology Fund Planning Project,China( No. 20100310)
文摘Weft knitted fancy fabrics are widely used in knitted garment design. Due to the complexity of the structures, their modeling and simulation needs to be solved in three-dimensional (3D) CAD developments. In this paper, 3D loop geometrical models of weft knitted fancy structures, including tuck stitch, jacquard stitch, transfer stitch and fleecy stitch, were developed based on an improved model of plain loop, and their central axes as some 3D space curves were achieved by using Non-Uniform Rational B-Splines (NURBS). The 3D visual simulation programme was written in C++ programming language using OpenGL, which was a function library of 3D graphics. Some examples of weft knitted fancy fabrics were generated and practical application of 3D simulation was discussed.
基金Young and Middle-aged Teacher's Education and Research of Fujian Province,China(No.JA15405)the Excellent Academic Leaders Project of Shanghai Municipal Science and Technology Commission,China(No.12XD1400400)+2 种基金the Natural Science Foundation of Shanghai Municipal Science and Technology Commission,China(No.13ZR1400500)the Fundamental Research Funds for the Central Universities,China(No.13D110126)National Innovation Experiment Program for University Students,China(No.131025501)
文摘Based on classic theory of elastic rod,the warp-knitted loop geometry in plane is independent of yarn properties,while there is a certain gap between the geometrical model and the actual fabrics.According to this problem,further analysis of loop geometry is done based on the theory of elastic rod with theoretical calculation and experiments.The theoretical analysis found that the distance between the contacted points at the loop root affected the loop geometry,and the distance was affected by the ratio of bending rigidity and the friction between yarns.The experiments,forming simple loop by taking the yarn as an elastic rod,found that the bending rigidity affected the loop geometry.Then the relationships between warp-knitted loop geometry in plane of metallic fabrics and wires properties were studied.The results show that metallic fabrics are more suitable for the theory of elastic rod;the friction and bending rigidity of wire yarns affect the loop geometry in plane.Also,the elongation of yarn affects the loop geometry in the actual warp-knitted fabric.
文摘In this paper,the relations between the parameters of stitch structure and the needle penetra-tion force,and the method by using the needle penetration force detected to evaluate the looplength and evenness of knitted fabric indirectly are analysed and discussed.A microcomputer system with a needle sensor and author’s program are used as a pick up setcombined with a data analysis system,for sampling and analysing the needle penetration forcedata.A lot of experimental research work has been done for knitted fabric of some kinds of knittedstitch and loop length.As a summary of this study,some conclusions can be drawn from the linearregression between the needle penetration force and the loop length.Then,the size and evenness ofthe loop length of knitted fabric can be indicated indirectly by detecting the value and variance ofneedle penetration force.It offers an effective method to detect and evaluate the evenness of knit-ted fabric with an efficiently high speed.