Design of a high-speed and high-load parallel robot
MENG Qizhi1,2, XIE Fugui1,2, LIU Xinjun1,2, YUAN Xin1,2, XUE Long3
1. Department of Mechanical Engineering(DME), Tsinghua University, Beijing 100084, China; 2. Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control, Tsinghua University, Beijing 100084, China; 3. Beijing Institute of Petrochemical Technology, Beijing 102617, China
Abstract：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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2022, Vol. 62 
