• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2016, Vol. 52 ›› Issue (13): 10-16.doi: 10.3901/JME.2016.13.010

• 机构学及机器人 • 上一篇    下一篇

4自由度并联机构刚体动力学模型*

贾凯凯1, 梅江平1, 刘松涛2, 田二勋1   

  1. 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
  • 出版日期:2016-07-05 发布日期:2016-07-05
  • 作者简介:

    贾凯凯(通信作者),男,1989年出生。主要研究方向为四自由度并联机械手运动控制。

    E-mail:tjuxueshao@163.com

  • 基金资助:
    * 国家自然科学基金重点资助项目(51135008); 20150803收到初稿,20160509收到修改稿;

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

JIA Kaikai1, MEI Jiangping1, LIU Songtao2, TIAN Erxun1   

  1. 1. Institute of Manufacturing Equipment and System, Tianjin University, Tianjin 300072,
    2. Chenxing (Tianjin) Automation Equipment Co., Ltd., Tianjin 301701);
  • Online:2016-07-05 Published:2016-07-05

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。

关键词: 单目标优化, 简化刚体动力学模型, 完备刚体动力学模型, SCARA运动

Abstract:

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.

Key words: complete dynamic model, simplified dynamic model, single objective optimization, SCARA motion