一种协作机器人工作空间灵活度的求解方法

A Solving Method for the Workspace Dexterity of Collaborative Robot

传统机器人工作空间灵活度主要采用逆运动学方法(IK)进行求解,而偏置的存在导致协作机器人的逆运动学求解困难,无法求解其工作空间灵活度.为此,提出了一种不需要进行逆运动学求解的改进方法.首先,对机器人偏置进行定义,并分析IK方法的不足.然后,借助服务球的概念得到满足服务点条件的几何约束,通过该几何约束得到求解灵活度的误差模型,并提出影响灵活度求解的误差参数E及工作空间灵活度指标λ.接着,分析改进方法中的参数n、n0、n1对E、λ的影响,并确定该参数的取值.最后,对比改进方法与IK方法可知,在保证求解准确性的前提下,改进方法比IK方法的求解时间短、计算效率高.通过求解具有偏置的协作机器人工作空间灵活度,证明了改进方法具有适应性强的特点.

The workspace dexterity of traditional robot is mainly solved by inverse kinematics(IK) method, which can not solve the workspace dexterity of collaborative robot because of the offset effect on the solution of inverse kinematics.So, an improved solving method without using the inverse kinematics is proposed. Firstly, the robot offset is defined and the deficiencies of the IK method are analyzed. Then, the geometric constraint satisfying the service point conditions is obtained with the service sphere, and the error model of dexterity is achieved by using the geometric constraint. Besides, the workspace dexterity index λ and the error parameter E which affect the dexterity solution are proposed. Then, the effects of parameters n, n0 and n1 on E and λ are analyzed in the improved method, and the values of the parameters are determined.Finally, through the comparison between the improved method and the IK method, it can be seen that the solution time of the improved method is shorter than the IK method and the computational efficiency is higher while guaranteeing the solution accuracy. The solving of the workspace dexterity of the collaborative robot with offset proves the strong adaptability of the improved method.