基于旋量理论Kane方程的挖掘机工作装置动力学分析

Dynamics Analysis of Bucket of Hydraulic Excavator Using Screw-based Kane's Equations

旋量是机器人研究中的重要工具,且其计算优势明显,建模过程几何意义突出。将挖掘机视作4自由度单开链机构,根据旋量理论建立了挖掘机动力学模型,旋量将挖掘机末端铲斗轨迹的位置与姿态变量分离,为提高控制精度奠定基础,且其计算简洁,利于实现挖掘机轨迹实时控制。文中根据旋量理论求取了挖掘机上部转台、动臂、斗杆与铲斗的物体雅可比矩阵,分别表示作用于挖掘机上部转台、动臂、斗杆与铲斗的主动力旋量与惯性力旋量,通过旋量形式Kane方程,建立了置于刚性水平土壤基上的挖掘机工作装置动力学模型。最后由相关挖掘机参数进行仿真,结果验证了所建模型的正确性。

Screw theory is an important tool in research of robots,also with its obvious advantages in computing,the geometric significance is more apparent in the process of modeling. By observing the hydraulic excavator as a single open chain mechanism with 4 degrees of freedom（ 4 DOF）,its dynamic equations were established with using screw-based Kane equations. The position and orientation variables of the trajectory of end bucket of excavator were separated based on screw theory,which laid a foundation for improving precision control,with its simplicity in computing,was helpful for implement real-time control of the trajectory of end bucket of excavator. The body Jacobian matrix of the upper rotational platform with the cab,boom arm and bucket of the excavator were gained based on the screw theory,which presented their generalized active wrench force and inertial wrench force in every respect. Through the screw type of Kane＇s equations,the dynamics model of end bucket of the excavator rested on a rigid horizontal soil foundation was established. Finally the correctness of the established model is verified from the simulation results of related parameters of the excavator.