食品和日化等领域存在大载荷桶装或袋装产品的两移动自由度搬运和装箱作业，降低了机器人自由度要求，但在机器人负载能力上提出了新的挑战。如何在构型综合层面实现机器人从无到有?如何在性能评价层面保障机器人从有到优?上述问题是研发高性能高速并联机器人的两大核心难题。该文围绕高速并联机器人的闭环支链优势特征，提出支链间耦合策略，建立了基于耦合策略的线几何图谱化高速并联机器人构型综合方法，实现了闭环支链型高速并联机器人构型设计；针对所设计的功能相同、结构近似的不同机器人构型，基于功率系数概念提出构型优选指标TSI（type selection index），实现了高速并联机器人的构型优选；根据上述研究指导了样机研发，并开展了实验研究与应用验证，测试表明：所研发的TH-UR2并联机器人具备高速高负载品质，在50 kg负载下其标准行程周期可达1.76 s，满足应用需求。
The food and retail chemical industries have many pick-and-place operations handling heavy loads with two translational degrees of freedom (DOFs), which reduce the mobility requirements but require robots that can handle heavy loads. Such processes need high-performance and high-speed parallel robots. This paper describes the advantages of closed-loop subchains of high-speed parallel robots and the coupling strategy between the subchains. The coupling strategy is then used to develop a line geometry mapping based synthesis method to design high-speed parallel robots with closed-loop subchains. A type selection index (TSI) based on the power coefficient in screw theory is used to guide the type selection between robot candidates with the same function and similar structures. A high-speed and high-load capability parallel robot TH-UR2 is then developed and tested. This robot can perform one standard travel cycle in 1.76 s with a 50 kg load, which meets the application requirements.
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