基于非线性最优化的服装混合维度放码方法

通过比较二维放码和三维放码的优缺点，提出了一种混合维度放码方法，将需要放码的二维裁片映射到三维人体上形成衣片，当三维人体变形时，对应的衣片也相应地发生变形.以三维衣片和二维裁片的边角特征作为放码的约束条件，构造非线性目标函数，问题转化为求解有约束的极小化问题，经过数学变换，问题最终转化为求解非线性方程组.多边形具有直角坐标和局部标架2种表示方法，充分结合直角坐标法便于添加放码约束以及局部标架法计算简便并具有良好收敛性的优点，利用局部标架法设定初值，通过直角坐标法实现对问题的最终求解.在求解迭代过程中通过对某些边和角的纠正来达到较好的放码结果.实例表明该方法非常有效.

Hybrid dimension garment grading based on nonlinear optimization

Comparing 3D grading methods with 2D grading methods, a hybrid dimension grading method was presented. The method maps a 2D pattern to be graded onto a 3D body to form a 3D garment patch which deforms with the body mesh. The edge and angle features of the pattern and the patch turn into the grading constraints. After constructing a nonlinear objective function and combining the grading constraints, the grading problem is converted into a nonlinear optimization problem, which requires to solving a nonlinear equation set after mathematic transformation. A polygon has two expressing ways, i.e. orthogonal coordinate and local coordinate frame, accordingly there are two formats of equation set. The first one is convenient to append grading constraints, and the second one has simple format and is well to be solved. The method links these two formats by using the local coordinate frame format to set the start value and the orthogonal coordinate equation format to satisfy all kinds of needs for grading. Some of the edges and angles can be rectified during the iteration process to improve the result. Some given examples show that this algorithm is effective and robust.