中文摘要：

为了发展新的并联机构形式,提出一种以圆弧弯曲截面钢带作为运动支链的6自由度钢带并联机器人机构形式。简要阐述钢带并联机器人结构组成与工作原理。采用基于变分原理的有限元静力学理论和线性屈曲分析理论建立求解钢带失稳临界力的屈曲方程。利用有限元软件ANSYS对不同结构参数的截面由圆弧弯曲形状过渡到平直形状的钢带进行失稳分析,得到钢带能承受的失稳力与结构参数的关系,并进行试验验证。对钢带并联机器人在平移运动位姿下的整机失稳机理进行系统研究,得到不同位姿参数与钢带并联机器人失稳临界力的关系。研究结果表明：弯曲截面结构的钢带能承受一定的压力,钢带失稳力随钢带圆弧截面中心角、钢带厚度增大而增大,随钢带长度增大而减小。对于机器人动平台作上升运动,在500 mm的高度,失稳临界力最大。而对于沿Y轴平动或沿Φ=60°平动且100 mm≤ρ≤200 mm的范围,对于沿极径ρ=500 mm平动且10≤Φ≤20的范围,失稳临界力均比较大。研究成果能用于优化钢带并联机器人的结构设计及确定刚度工作空间。

英文摘要：

In order to develop new parallel mechanisms,a 6-DOF steel band parallel robot with kinemics chain composede of steel band having arc-shaped cross section is presented.The structure and principle of the steel band parallel robot are illustrated.Finite element analysis theories including static and buckling analysis,which are based on the variational principle,are used to determine the buckling equation which can compute the instability critical load.Different structural steel bands with cross sections from arc to straight line are analyzed by using FE software ANSYS,and relationships between structural parameters and the instability critical load are obtained.The simulation results are evaluated by experiments.Instability property analysis of steel-band parallel robot as a whole is analyzed systematically at different postures of translation motion,and the relationships between posture parameters and instability critical force are obtained.The results show that steel band with cross sections from arc to straight line can receive certain pressure,the instability critical force increases in direct ratio to the magnitude of central angle or thickness,but in inverse ratio to the length of steel band.For ascending motion of mobile platform,the instability critical force reaches maximum at the altitude of 500 mm which can be specified as the optimal posture.For mobile platform translating along Y axis or the path with Φ=60° at the same altitude,when 100 mm≤ρ≤200 mm,the instability critical forces are relatively great.For mobile platform along the path of ρ=500 mm with 10≤Φ≤20 at the same altitude,the instability critical forces are also relatively great.These results can be used to optimize structural design and determine the stiffness working space of a steel band parallel robot.