摘要
显式动力学模型是并联机构控制器设计的基础,由于并联机构的闭环结构特点,导致其显式动力学建模过程通常比较复杂。为了避免动力学建模过程中繁琐的求导过程,考虑关节摩擦并基于牛顿-欧拉法对3SPS+1PS并联机构的显示动力学模型进行了研究。在并联机构运动学及受力分析的基础上,建立其具有一般形式的动力学模型,选取动平台上球铰链所在位置点的运动学参数作为中间变量,并将其表示为各运动参数的函数,通过参数替换,最终得到包含人工髋关节、推力球轴承、球铰链及电动缸等处摩擦且具有显式形式的动力学模型。将所建立并联机构动力学模型的数值仿真结果与实测结果进行对比分析,验证了所建立模型的有效性。得到的动力学模型可用于并联机构的动力学控制器设计及摩擦补偿控制研究,所使用的方法同样适用于其他构型并联机构的显式动力学建模。
Explicit dynamical model is the basis of controller design of parallel manipulator. Caused by the close-chain kinematic structure, dynamical model of parallel manipulator is usually complex. To avoid the tedious derivation process of dynamic modeling, explicit dynamical model of a 3SPS＋IPS parallel manipulator is established based on Newton-Euler method, and in the dynamical model, joint friction is considered. Based on the kinematics analysis and the force analysis, dynamic model of the 3SPS＋IPS parallel manipulator is established. And then, kinematics parameters of the installation sites of the spherical hinges on the moving platform are selected as the intermediate variables, and the intermediate variables are related to the kinematics parameters of the joints. By parameter replacing, the explicit dynamical model of the 3SPS＋IPS parallel manipulator with friction of the artificial hip joint, the thrust ball bearing, the spherical hinges and the electric cylinders is obtained. Comparisons between the results from the established model and the results from the actual experiments verify the correctness of the established model. The explicit dynamical model can be applied to controller design and friction compensation control. The methodology can be also used to derive the dynamics of other manipulators.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2017年第1期28-35,共8页
Journal of Mechanical Engineering
基金
国家自然科学基金(51275512)
江苏高校优势学科建设工程和江苏高校品牌建设工程资助项目
