摘要
所述广义负载模拟器采用主从式双并联12自由度机构(MSDPM)进行三维空间力和力矩的复合加载,由于采用了结构化的顺应机构(SCM),致使加载机构(GLS)关节空间耦合特性发生重大变化。本文首先建立了GLS和SCM的独立动力学模型,根据约束条件进行简化并整合。考虑到控制器的设计是在关节空间进行,基于雅克比变换给出了关节空间等效动力学模型。据此指出关节空间多通道交联耦合的根本原因在于刚度矩阵和质量矩阵的非线性强耦合,并给出了耦合矩阵的具体表达式。基于模型对各个自由度下的耦合特性进行仿真研究。结果表明,两种耦合形式都超出了不解耦条件,但在不同的加载目标值和扰动位姿下,二者的影响程度差异巨大。该结论对于控制器的设计有重要的参考价值。
A generalized load simulator is proposed in this paper.It uses a master-slave dual-parallel 12-DOF manipulator（MSDPM） to reproduce spatial force and torque.Because of the structured compliance mechanism（SCM） to be uesd,joint-space coupling characteristics of load mechanism（GLS） changes significantly.This paper firstly establishes an independent dynamics model of GLS and SCM,and the model is simplified and united by constraints.Considering that controller design is carried out in a joint-space.A equivalent joint-space dynamics model is deduced based on Jacobian matrix.Then ultimate reasons for multi-channel cross coupling are concluded as the strong nonlinear coupling of stiffness matrix and mass matrix,and explicit expressions of couple matrixes are given.Based on the model,the coupling characteristics on each DOF are studied via simulation.Results show that both stiffness coupling and mass coupling are too strong to ignore,but both influences are quite different under varying target load and disturbed pose.This work is meaningful to the design of controller.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2010年第5期1463-1467,共5页
Journal of Astronautics
基金
国家自然科学基金资助项目(50375139)
关键词
广义负载模拟器
关节空间
耦合特性
并联六自由度机构
顺应机构
Generalized load simulator
Joint-space coupling
Characteristics
Parallel 6-DOF manipulator
Compliance mechanism
