4自由度并联机构刚体动力学模型  

Rigid-body Dynamic Model of a Four-DOF Parallel Mechanism

作　　者：贾凯凯 梅江平[1] 刘松涛 田二勋 

机构地区：[1]天津大学制造装备与系统研究所,天津300072 [2]辰星(天津)自动化设备有限公司,天津301701

出　　处：《机械工程学报》2016年第13期10-16,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金重点资助项目(51135008)

摘　　要：以一种具有空间SCARA运动(三维平动和一维转动)的四自由度并联机构为研究对象,系统研究其简化刚体动力学模型的创建方法,提高了力矩求解精度。在运动学分析的基础上,利用虚功原理,建立机构的完备刚体动力学模型,并利用ADAMS校验该模型的正确性。考虑机构各活动构件的结构和运动状态,建立机构的单变量简化刚体动力学模型,奠定了变量优化的模型基础。以机构沿标准轨迹运动时,将完备模型和简化模型计算所得的单轴驱动力矩差值的最大值的绝对值的平均值作为优化目标,分析各尺度参数对优化目标的影响规律,为简化模型的最优变量确定提供指导。以一组给定参数为例,利用单目标优化方法,求解出变量最优值,通过与现有简化方法对比,验证了所述方法的有效性。Focused on a 4-DOF parallel mechanism with the spatial motion called SCARA（three dimensional translation and one-dimensional rotation）, the establishment of its simplified dynamic model of rigid body is systematically researched to improve the accuracy to solve torque. Based on the kinematics analysis, the complete dynamic model of rigid body is established with the virtual work principle, and its accuracy is examined by ADAMS. To reduce the computational complexity, taking the structure and state of motion in every moving part of the mechanism into consideration, the simplified dynamic model of rigid body with single parameter is established. For the expected simplification, when the mechanism is moving along the standard trajectory, the average of maximum absolute torque difference between values solved from the complete dynamic model and the simplified dynamic model as optimization function are taken and the relation between the function and scale parameters is analyzed. Under the authentication of the analysis results, based on a set of given parameters, the optimal value is obtained by using the single objective optimization method. The validity of the method is verified through a set of image contrast compared with existed theories.

关 键 词：SCARA运动 完备刚体动力学模型 简化刚体动力学模型 单目标优化 

分 类 号：TH122[机械工程—机械设计及理论]