光学 精密工程, 2018, 26 (12): 2940, 网络出版: 2019-01-27
可展开固体反射面机构设计及运动学分析
Mechanism design and kinematic analysis of deployable solid reflector mechanism
固体反射面机构 可展单元 运动学分析 回转角 结构尺寸 收拢率 solid reflector mechanism deployable unit kinematic analysis rotation angle structure size folding rate
摘要
针对传统固体反射面机构主反射面型面精度和收拢率较低的问题, 设计了一种可展开固体反射面机构。首先, 提出4种固体反射面机构可展单元构型并对其机构自由度进行分析, 对比分析构型方案优缺点确定构型方案4作为可展单元基础构型, 并对其结构和展开原理进行详细设计。通过D-H坐标变换建立该机构可展单元的运动学模型, 根据几何约束条件建立机构位置矢量方程, 利用向量封闭投影法解出各回转角间的关系, 结合MATLAB软件编程对机构的位置、速度和加速度进行分析。应用ADAMS软件建立机构仿真模型, 验证了机构运动学分析的正确性。最后根据机构中回转角的限制条件和结构尺寸关系, 分析回转角和结构尺寸对可展开固体反射面机构收拢率的影响, 确定2.2 m可展开固体反射面机构的回转角和旋转角分别为78°和30°, 中心圆盘半径、铰支座一孔纵向尺寸、切换连杆横向尺寸、纵向尺寸分别为245, 8, 40, 18 mm, 收拢率为0.326, 从而为可展开固体反射面机构的设计提供参考。
Abstract
To solve the problems of low accuracy and folding rate of the main reflective surface of a traditional solid reflector mechanism, a deployable solid reflector mechanism was designed in this paper. First, the configurations of four types of deployable units were proposed, and their degrees of freedom were analyzed. After comparing and analyzing the advantages and disadvantages of the configuration schemes, configuration scheme 4 was defined as the basic configuration of the deployable unit, and its structure and deployment principle were designed. Then, based on the D-H coordinate transformation, a basic deployable unit kinematic model was established. According to the geometric constraints, the position vector equation was established; the relationship between rotation angles was established by the vector closed-form projection method; and the position, velocity, and acceleration were analyzed. Simultaneously, ADAMS software was used to establish the mechanism simulation model and verify the correctness of the kinematics analysis. Finally, based on the relationship between the rotation angle and the structure size of the mechanism, the effects of rotation angle and structure size on the folding rate were analyzed, and the rotation angles and of a 2.2 m deployable solid reflector mechanism are determined to be 78° and 30°, respectively. The center disk radius, the longitudinal dimension of hinge support hole, the transverse dimension, the longitudinal dimension of the switching link, and the folding rate are 245 mm, 8 mm, 40 mm, 18 mm, and 0.326 respectively, which provide a reference for the design of the deployable solid reflector mechanism.
王建东, 郭宏伟, 刘荣强, 罗阿妮, 刘贺平. 可展开固体反射面机构设计及运动学分析[J]. 光学 精密工程, 2018, 26(12): 2940. WANG Jian-dong, GUO Hong-wei, LIU Rong-qiang, LUO A-ni, LIU He-ping. Mechanism design and kinematic analysis of deployable solid reflector mechanism[J]. Optics and Precision Engineering, 2018, 26(12): 2940.