三转动并联平台速度精度可靠性分析

Speed accuracy reliability analysis of the tri-rotational parallel mechanism platform

机器人的速度精度可靠性是评价机器人精度的重要考核指标。以三转动并联平台为例,在并联平台运动学模型的基础上,给出了末端执行器速度精度可靠性的概念以及速度精度可靠性的状态函数,进而根据一次二阶矩法对并联平台末端执行器速度精度可靠度进行了求解。结合算例,给出了该并联平台在某一确定位置上的速度精度可靠度,并在可靠度分析的结果上,运用可靠性灵敏度设计算法给出了相关随机变量的可靠性灵敏度变化规律。通过控制并联平台的位置变化,给出了其任意位置的可靠度,为合理规划其工作区域提供理论依据。

The robot's speed precision reliability is an important evaluation indexes to evaluate the precision of the robot.Taking tri-rotational parallel mechanism platform for example,the concept of the speed accuracy reliability of the end effector and the state function of speed accuracy reliability is presented on the basis of the kinematics model of the parallel mechanism platform.Then the speed accuracy reliability of the robot is solved by using the first-order second-moment and perturbation method.Combined with an example,the velocity accuracy reliability about the parallel platform in a certain position is given,and on the basis of the analysis of the reliability,the reliability sensitivity design algorithm is used to figure out the changing law of the reliability sensitivity of correlated random variables.The reliability of arbitrary position of the parallel mechanism platform is given by controlling the position of the parallel platform,it can provide theoretical basis for planning the parallel mechanism platform work area reasonably.