5R串联机器人的静态误差分析及优化方法

摘要

以5自由度串联机器人为研究对象,采用D-H法建立该机器人运动学模型,并利用微小位移合成法建立该机器人的位置误差模型,通过理论计算得到末端位置静态误差表达式.以末端位置最大误差值为评价指标,运用控制变量法,研究各连杆参数误差对该串联机器人末端位置精度的影响程度.提出一种利用Jacobi矩阵将末端运动轨迹在Descartes坐标下的误差转换为关节角修正量的算法,并对其运动过程中的关节转角进行优化.仿真结果表明,该优化方法正确、有效,可有效降低运动路径误差至3mm以下.%A kinetic model of a robot with five degrees of freedom was built as the research object. By using the small displacement composing method, the error model was also established to reach the static error expressions of the terminal position.The level of influence of parameter errors on terminal position accuracy of the series robot was studied by using the variable controlmethod,with the max error serving as the evaluation indicator. An algorithmwas proposed which transformed the terminal trajectory error in Descartes coordinates to correction of joint angles by using Jacobi matrixes. Then the turning angles in the process wereoptimized.The simulation results showed the rationality and effectiveness of this algorithm, which lowered the trajectory error to a level of under 3mm.