一种三自由度冲压搬运机械手的尺度综合

Dimensional synthesis of a 3-DOF handing manipulator in press line

设计了一种用在管材冲压线上,代替人工完成上、下料动作的三自由度冲压搬运机械手,对该机械手进行工作空间求解和优化设计,以运动学、动力学性能指标为目标函数,以工作空间和静刚度指标为约束条件,以杆件参数和拉簧参数为设计变量,建立机械手的多目标优化模型。用非支配排序遗传算法(Non-dominated Sorting Genetic Algorithm-Ⅱ,NSGA-Ⅱ)求解多目标优化模型,在Pareto最优解集中优先选择降低电动机2极限力矩的解,且所选解不能大幅削弱其他性能指标。将所选解代入运动学、动力学方程中进行理论计算,结果表明,优化后机械手的运动学、动力学性能指标均有了一定程度的改善,为结构设计和运动控制提供了依据。

A novel 3-DOF hybrid manipulator was presented to pick and place the tubes on punch line. The workspace and optimi- zation of the mechanism structure were carried out, several evaluation indexes of kinematics and dynamics performance are estab- lished for the object functions, workspace and static stiffness index for the constrains, parameters of level and tension spring for the design variables, and then a standard multi-objective optimization model can be built. The dimension synthesis is carried out by solving the multi-objective optimization with Non-dominated Sorting Genetic Algorithm-II （NSGA-II）, the result of reducing driv- ing torque of the motor 2 was selected in Pareto optimal solutions, meanwhile the selected solution can not significantly impaired other evaluation indexes. The selected solution was verified with kinematics, dynamics equation, the results show that optimized manipulator kinematics and dynamics performance has been greatly improved, and the theoretical foundation was brought forward to guide structural design and motion control.