Optimum design is proven significant for improving task performances of robotic manipulators under certain constraints. However, when it is utilized for collaborative robots (Cobots), there are still many challenges such as complex smooth surface links, time-varying kinematic configurations, computational expensiveness, and nonstructural parameter optimization. Therefore, based on orthogonal design experiment (ODE) and finite element substructure method (FESM), a multi-objective optimum design method of Cobots is proposed with the structural dimensions and parameterized joint components as the optimization variables and the natural frequency, the Cartesian stiffness, and the mass of the robot as optimization objectives. Firstly, to obtain multiple global performance indexes (GPIs) of robots in real-time and efficiently, the FESM model of Cobots is established which can preserve the accuracy of the finite element method (FEM) while ensuring the computational efficiency. Then, the gray relational analysis method (GRAM) is used to construct the multi-objective optimization function which includes the global first-order natural frequency index (GFNFI), the global elastic deformation index (GEDI), and the mass of robots. The ODE is constructed, and the structural dimensions and parameterized joint components are taken as influencing factors. According to the orthogonal array (OA), the degree of gray incidence under different levels of influencing factors is solved. And the optimal combination of influencing factor levels is obtained by range analysis (RA), which is used to guide the design of Cobots. Finally, a Cobot SHIR5-I is taken as an illustrative example to perform optimum design in this paper.

事实证明，在某些约束条件下，最佳设计对于提高机械手的任务性能具有重要意义。但是，当将其用于协作机器人（Cobots）时，仍然存在许多挑战，例如复杂的平滑曲面链接，时变运动学配置，计算昂贵和非结构参数优化。因此，基于正交设计实验（ODE）和有限元子结构法（FESM），提出了一种以结构尺寸和参数化关节构件为优化变量，固有频率，笛卡尔刚度为基础的多目标Cobots优化设计方法。 ，并将机器人的质量作为优化目标。首先，要实时，高效地获取机器人的多个全局性能指标（GPI），建立了Cobots的FESM模型，该模型可以在保证计算效率的同时保持有限元方法（FEM）的准确性。然后，使用灰色关联分析法（GRAM）构造多目标优化函数，该函数包括全局一阶固有频率指数（GFNFI），全局弹性变形指数（GEDI）和机器人质量。构造了ODE，并以结构尺寸和参数化的关节部件为影响因素。根据正交阵列（OA），解决了不同水平的影响因素下的灰色入射度。并通过范围分析（RA）获得了影响因素水平的最佳组合，用于指导Cobots的设计。最后，