Abstract: In order to improve the efficiency of knitted fabric simulation and ensure the authenticityof the simulation effect, a method of using the periodicity of yarn model is proposed. The method first establishes the correspondence between the mesh and the yarn model, and then simulates the mesh model and the yarn model separately. To speed up the mesh simulation and improve the deformation effect under low resolution mesh, the adaptive remeshing technique is used to appropriately subdivide and coarsen the mesh model at the corresponding location according to the degree of deformation, and to calculate the strain on the mesh surface. In terms of microscopic deformation details, the minimum repetitive cell of the yarn is simulated using different strain parameters as input, and the relationship between the input strain parameters and the energy density of the repetitive cell is obtained. Finally, the simulation results are mapped onto the mesh model that has been output by the mesh simulation through the input of the strain parameters obtained in the mesh model. A simulation experiment is taken in fabrics of five different knitting methods. The results show that this method is closer to the real deformation effect than the traditional mesh simulation method, and the number of model vertices and meshes used in the simulation process is reduced by 20%-30% compared with the input mesh, and the time efficiency can be improved by up to 39.7%.

Key words: adaptive remeshing, yarn model, mass-spring system, knitted cloth simulation

摘要： 为了提高针织物仿真效率并保证仿真效果的真实性,提出一种利用纱线模型周期性的方法。该方法首先建立网格与纱线模型之间的对应关系,然后对网格模型与纱线模型分别进行仿真。在整体形变效果方面以网格仿真为主,为了加快网格仿真速度、提高低分辨率网格下的形变效果,仿真过程中使用自适应网格划分技术,根据形变的程度适当地细分与粗化相应位置的网格模型,并计算网格面的应变。在微观形变细节方面,使用不同的应变参数的输入对纱线最小重复单元进行仿真,得到该重复单元的输入应变参数与能量密度之间的关系。最后通过网格模型中得到的应变参数输入,将仿真结果映射到经过网格仿真输出的网格模型上。对5种不同针法的织物进行仿真实验,结果表明该方法比起传统网格仿真方法有更接近真实的形变效果,仿真过程中使用的模型顶点与网格数量相比输入网格减少20%～30%,并且在时间效率上最多能够提升39.7%。

关键词: 自适应网格划分, 纱线模型, 弹簧质点模型, 针织物仿真