一种4自由度高速并联机械手动态特性分析

Dynamic Analysis of a 4-DOF High-Speed Parallel Manipulator

以一种可实现SCARA运动的4自由度高速并联机械手(Cross-Ⅳ机械手)为研究对象,将运动学理论和虚拟仿真相融合,研究一种分析高速/高加速运动机构轨迹误差的系统性策略和方法.以运动学逆解模型为基础,获得Cross-Ⅳ机械手在给定运动轨迹和运动规律时的驱动关节位置数据曲线.利用三维CAD模型,通过有限元软件ANSYS和机械动力学软件ADAMS联合建模,创建Cross-Ⅳ机械手的刚柔混合模型.将驱动关节位置数据代入刚柔混合模型,仿真得到系统重力和惯性力引起的构件弹性形变导致的末端轨迹误差,并分析各向轨迹误差和综合误差随负载、运动规律和工作平面不同的变化规律,为机械手轨迹规划、运动规律优选和误差控制提供理论支撑和分析方法.

Taking a 4-DOF SCARA type high-speed parallel manipulator(Cross-Ⅳ manipulator)as the research ob-ject,by integrating kinematical theory with virtual simulation analysis,a systematic strategy/method was presented for the analysis of trajectory error in a type of high-speed/acceleration mechanism.Based on the inverse kinematical analysis,the position data of actuated joints was obtained with given trajectory and motion law.By means of combin-ing the functions of ANSYS and ADAMS,the rigid-flexible hybrid model of Cross-Ⅳ manipulator was estab-lished.Importing the position data of actuated joints into the rigid-flexible hybrid model,a simulation that considered gravity and inertia force was formulated to calculate the trajectory error caused by elastic deformation of links.The orientation trajectory error and total trajectory error were researched under different conditions of payload,motion law and work plane.This paper serves to provide a theoretical support and analysis method for trajectory planning, selection of motion law and error control etc.