Abstract Combining the characteristics of parallel and series robots, hybrid robot has a good application prospect of machining. The dimensional synthesis, which is highly related to the performance, is studied based on a 5-DOF hybrid robot in this paper. The construction methods of optimization objectives which better reflect the motion range, stiffness and the kinematics performance are proposed. The bounding box theory is introduced to construct indexes of the actual motion ranges while considering the motion interference caused by mechanisms. And the maximum and minimum stiffness indexes of parallel structure based on the modified stiffness model and the comprehensive kinematics performance index based on condition number are also designed. Four constraints including installation, joint motion limitation, joint load limitation and validity of data define the feasible region. It is found from the optimization results that motion range changes more greatly than other objectives, which makes the solution with better motion ranges a higher priority. The correlation between dimensional parameters and optimization objectives is analyzed to guide the improvement of optimization model and provide references for dimensional synthesis of other hybrid robots.

中文翻译：

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五自由度混合机器人的尺寸综合

摘要 混合机器人结合并联和串联机器人的特点，在机械加工中具有良好的应用前景。本文基于五自由度混合机器人研究了与性能高度相关的维度合成。提出了更能反映运动范围、刚度和运动学性能的优化目标的构建方法。引入包围盒理论，在考虑机构引起的运动干扰的同时，构建实际运动范围的指标。并设计了基于修正刚度模型的并联结构最大最小刚度指标和基于条件数的综合运动学性能指标。四个约束，包括安装、关节运动限制、联合载荷限制和数据的有效性定义了可行区域。从优化结果中发现，运动范围变化比其他目标更大，这使得具有更好运动范围的解具有更高的优先级。分析尺寸参数与优化目标的相关性，指导优化模型的改进，为其他混合机器人的尺寸综合提供参考。