Stiffness and Dynamics Analysis of SCARA Parallel Mechanism

被引：0
|
作者：
Zhu W. [1 ]
Guo Q. [1 ]
Ma Z. [1 ]
Shen H. [1 ]
Wu G. [2 ]
机构：
[1] School of Mechanical Engineering, Changzhou University, Changzhou
[2] School of Mechanical Engineering, Dalian University of Technology, Dalian
来源：
Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery | 2019年 / 50卷 / 10期
关键词：
Dynamics; SCARA parallel mechanism; Stiffness; Virtual spring;
D O I：
10.6041/j.issn.1000-1298.2019.10.044
中图分类号：
学科分类号：
摘要：
There is a wide range of industrial applications for the 4-DOF parallel mechanism which can achieve SCARA type output motion (three dimensional translation and one dimensional rotation). A novel four-degree-of-freedom high-speed parallel robot mechanism for SCARA was proposed, which consisted of two RSS branches and two R(SRS)2R branches. Firstly, the topological structure characteristics such as the POC set of moving platform and mobility were first obtained based on the design theory of position and orientation characteristic (POC) set. Secondly, the virtual spring method was used to establish the stiffness model of the branch and the static of the branch was given. The differential mapping of the virtual joint deformation to the end deformation in the branch was obtained by the spin method and the Cartesian stiffness matrix at the end of the mechanism was obtained according to the static equation. By means of a nondimensionalization of the stiffness matrix, the 6×6 inhomogeneous stiffness matrix was decomposed into two homogeneous sub-matrices, of which two performance indices, corresponding to the translational and rotational stiffnesses, were defined to evaluate the stiffness behaviors of the manipulators. And the stiffness index analysis of the mechanism was carried out, and the stiffness characteristics of the mechanism in different working planes were analyzed. In addition, the dynamic analysis of the mechanism was performed to solve the velocity and acceleration of the active pair, the passive pair and the moving platform of the mechanism. The dynamic equation of the mechanism was established by using the virtual work principle. Finally, the simulation was compared with the ADAMS three-dimensional model simulation to verify the dynamics. The correctness of the modeling laid the foundation for further research and practical application of the organization. © 2019, Chinese Society of Agricultural Machinery. All right reserved.
引用
收藏
页码：375 / 385
页数：10
相关论文
共 17 条
  • [11] Pashkevich A., Chablat D., Wenger P., Stiffness analysis of overconstrained parallel manipulators, Mechanism & Machine Theory, 44, 5, pp. 966-982, (2009)
  • [12] Xia Y., Lu N., High-precision Euler-Bernoulli beam element for stability analysis of beam-beam structures, Journal of Shenyang Jianzhu University (Natural Science Edition), 22, 3, pp. 362-366, (2006)
  • [13] Kovecses J., Ebrahimi S., Parameter analysis and normalization for the dynamics and design of multibody systems, Journal of Computational & Nonlinear Dynamics, 4, 3, pp. 340-341, (2009)
  • [14] Taghvaeipour A., Angeles J., Lessard L., On the elastostatic analysis of mechanical systems, Mechanism and Machine Theory, 58, pp. 202-216, (2012)
  • [15] Li Y., Wang Y., Coordinate transformation of rotating inertia tensor of robot, Robot, 2, pp. 31-35, (1992)
  • [16] Sharifzadeh M., Tale M.M., Kalhor A., Et al., An experimental dynamic identification & control of an overconstrained 3-DOF parallel mechanism in presence of variable friction and feedback delay, Robotics & Autonomous Systems, 102, pp. 27-43, (2018)
  • [17] Hu B., Wang A., Li Z., Et al., Kinematics and dynamics analysis of a dynamic seat based on a new 4-UPS+PSPR parallel mechanism, Journal of Yanshan University, 42, 1, pp. 11-21, (2018)
12