中文摘要：

针对传统手工划线精度差、工效低、劳动强度大等缺点，提出了一种简单实用用于平面划线执行机构的二自由度并联机构，采用拉格朗日法建立了机构的动力学模型，推导了机构动力学方程；以工业排风扇叶片划线为应用背景，拟合了叶片得边界曲线方程，并运用Matlab软件仿真得出机构末端执行点（划线头）作叶片轨迹运动时机构动力学变化规律；得出该二自由度并联机构动力学性能较好，同时由于机构自由度少、结构简单、易于控制等特点，因而适合于曲率半径较大的曲线或者直线形状零件的划线作业。

英文摘要：

In view of the drawbacks existing in traditional manual scribing such as poor accuracy, low effi- ciency, large labor intensity, etc. A 2-DOF parallel mechanism is proposed to be used in the actuator {or plane scraper. Based on the Lagrange equation, the dynamic equation of the mechanism is derived. Some curve equations were fitted based on industrial exhaust fan blade scribing. The dynamics is established that the terminal operating point finished this curve track by using Matlab. It is concluded that the 2-DOF parallel mechanism has good dynamic performance, and because of its less degree of freedom, simple structure and easy control, it is suitable for marking assignments that have curve with large radius or parts with straight shape.