摘要
为满足钢铁搬运行业的应用需求,提出了一种新型三移一转并联机构。该机构的每条分支包含驱动支链RPR和执行支链RPaPaR,其执行支链中的平行四边形铰链Pa具有封闭环结构特性,使机构有较大的刚度。借助螺旋理论分析了该并联机构的自由度。采用机构杆件之间的几何条件以及坐标变换求出机构的位置逆解,得到驱动杆件与动平台位姿的关系。根据钢铁搬运任务需求,使用五次多项式计算出动平台分段驱动函数,在仿真软件ADAMS中实现机构末端由初始到目标位置的轨迹规划,并由驱动杆的仿真数据与计算数据一致,验证了机构位置逆解数学模型的正确性。利用PID控制器搭建机构的位置控制模型,实现动平台的实际位置与理论位置轨迹的一致性。使用CAD变量几何法得到了机构的可达位置工作空间,并对其进行了分析,得出工作空间分布特点。
To satisfy the application needs of the steel handling industry,a novel parallel mechanism with three translations and one rotation is proposed.Each branch of the mechanism contains the actuated limb RPR and the passive limb RPaPaR,where the passive limb contains the parallelogram joint Pa,which has closed-loop structural characteristics,giving the mechanism a large stiffness.The degrees of freedom of the parallel mechanism are analyzed using the screw theory.The position inverse solution of the mechanism is constructed by using the geometric conditions between the mechanism links and the coordinate transformation,obtaining the relationship between the actuator and the position and posture of the moving platform.According to the steel handling task requirements,the segmental drive function of the moving platform is calculated using the fifth polynomial,and the trajectory planning of the end of the mechanism from the initial to the target position is realized with the simulation software ADAMS,and the simulation data of the actuator is consistent with its calculated data,which verifies the correctness of the mathematical model of the inverse position solution of the mechanism.The position control model of the mechanism is constructed by using the PID controller,realizing the actual position of the moving platform is consistent with the theoretical position trajectory.The accessible position workspace of the mechanism is obtained and analyzed using the CAD variable geometry method,deriving the workspace distribution characteristics.
作者
陈会元
王蕊
张明泽
武海军
张金柱
CHEN Huiyuan;WANG Rui;ZHANG Mingze;WU Haijun;ZHANG Jinzhu(College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030000,China)
出处
《组合机床与自动化加工技术》
北大核心
2024年第2期13-17,23,共6页
Modular Machine Tool & Automatic Manufacturing Technique
基金
国家自然科学基金项目(51905367)。
关键词
并联机构
运动学分析
仿真
轨迹规划
位置控制
工作空间
parallel mechanism
kinematic analysis
simulation
trajectory planning
position control
workspace
