以设计全柔性多自由度过驱动并联机构为目标,研究了平面3-DOF4RRR过驱动并联机构的最优综合问题.从一般四分支3-DOF平面并联机构出发,建立了机构的运动学模型;给出了机构的4种可能拓扑结构分类,对不同拓扑结构类型机构的运动学和力学性能进行了分析比较.建立了并联机构全工作空间操作性改善优化模型,采用遗传算法进行优化设计并给出了实例,根据优化实例的结果设计制造了平面全柔性三自由度过驱动并联机构.以上方法对其它全柔性并联机构的优化设计具有参考价值.
Optimal synthesis procedure of a planar 3-DOF 4RRR overactuated parallel mechanism is investigated to design a full-compliant multi-degree-of-freedom overactuated parallel mechanism. Firstly, the kinematic models are developed for the general 3-DOF four-limbed planar parallel mechanism. Then, the possible topologies of the mechanism are classified into four categories, and their kinematic and dynamic performances are analyzed and compared. A global optimization model for the parallel mechanism is established to improve its manipulability, and a numerical optimization example using genetic algorithm is presented..Based on the numerical result, a planar 3-DOF full-compliant overactuated mechanism is designed and fabricated. The optimal synthesis procedure can be applied to other full-compliant mechanisms.