基于AutoCAD VBA液压挖掘机工作装置运动学分析

液压挖掘机工作装置可视为多自由度机械手,具有高效灵活的特点。不考虑其回转运动,工作装置属平面连杆机构。铲斗位姿与关节夹角之间的变换常用齐次坐标变换或解析法,逆向运动学问题的求解则用几何法。在AutoCAD环境下,建立工作装置的简化模型,借助二次开发语言,对运动学问题进行了研究。编程实现了图解过程,省略了复杂的公式推导,得出工作范围包络曲线及工作参数。设置铲斗的姿态角为某一数值,得出了齿尖轨迹为水平直线和竖直直线时的运动学逆解,并实现了工作装置的运动仿真。

Kinematics analysis of working device of hydraulic excavator based on AutoCAD VBA

Hydraulic excavator working device can be regarded as multi-DOF manipulator with high efficiency and great flexibility.Without considering its rotary movement,working device belongs to planar linkage mechanism.The conversion between bucket position and joint angles is solved by coordinate transform method or analytic method, while the geometry method is used in solving inverse kinematics problem.In the AutoCAD environment a simplified model of the working device is established.Then the kinematics problems are studied with the use of secondary development language.Since the programming is realized by graphic method,complex formula derivation is omitted and the curves of workspace and working parameters are obtained.With the bucket attitude angle being set with a value,inverse kinematics solutions are obtained when the tooth tip trajectories are horizontal line and vertical line.And the motion simulation of the working device is realized.