Abstract:

Objective In order to shorten the product development cycle, improve the design efficiency of multi-needle bed weft-knitted fabrics, and address the inconvenience caused by the coexistence of multiple code systems (loop codes and cam codes) in current weft-knitting computer aided design (CAD) systems, this paper digitizes the working state of multi-needle bed weft-knitted fabrics based on their knitting principles and structural characteristics. By using matrix operations, a rapid design method for multi-needle bed weft-knitted fabrics is achieved.

Method Based on the digitalization of the working states of knitting needles and cams in multi-needle bed weft-knitted fabrics, a weft-knitting color code system is created, establishing the relationship between loop shapes, knitting needle, and cam configurations. The mathematical relationships among the knitting process matrix, cam configuration matrix, and knitting needle arrangement matrix are constructed. The algorithm is incorporated into the weft-knitting CAD system with an added automatic error correction feature for ease of application.

Results In the design of multi-needle bed weft-knitted fabrics, there are three main needle arrangement methods: single-side needle arrangement, double-side aligned needle arrangement, and double-side staggered needle arrangement. Based on the triangular working states of the knitting needles in different knitting conditions, nine loop code systems were constructed, and matrices for knitting needle arrangement, triangular cam configuration, and knitting process were created. The three matrices were mathematically expressed to derive the conversion relationships between them. After establishing the transformation relationships of the fabric matrices, an intelligent error correction design was implemented to address potential issues in different types of fabric designs. The algorithm developed in this study can be applied to the weft-knitting CAD system. The algorithm's correctness was verified through specific product designs, such as the successful transformation between the triangular cam configuration, knitting needle arrangement, and knitting process diagrams for the Dutch double pearl fabric using matrix operations. Finally, the algorithm was implemented into the weft-knitting CAD system using programming tools such as C# and Visual Studio, enabling automatic error correction and achieving fast, accurate, and intelligent product design and production on the machine.

Conclusion This paper primarily investigates the digital design method for multi-needle bed weft-knitted fabrics. Based on the knitting principles of multi-needle bed weft-knitted fabrics, a digital loop system was established. By utilizing matrix operations, a new method was provided for the rapid, convenient, and intelligent processing in weft-knitting CAD design.

Key words: three-position weft-knitted, digital design method, weft-knitted fabric design, knitting pocess, weft-knitted CAD