3-RPC定位机构结构设计

Structural Design Forthe 3-RPC Positioning Mechanism

集成式全柔性并联定位机构具有无摩擦和高稳定性的优点,但其结构设计相对复杂,定位精度低,在一些超精密定位领域无法达到定位要求。基于同构性的集成式全柔性并联定位机构,引入拓扑优化设计理论,设计出与同构性集成式全柔性并联定位机构运动特性一致的3-RPC型全柔顺并联定位机构。首先,以3-RPC并联定位机构为研究对象,通过微位移法求解出其输入输出间的映射关系。然后,建立3-RPC集成式全柔性并联定位机构和3-RPC全柔顺并联定位机构三维模型。最后,通过有限元软件对两种定位机构进行静、动力学分析。结果表明:3-RPC全柔顺并联定位机构在定位精度和抗振性均优于同构性的集成式全柔性并联定位机构。

The integrated flexible parallel positioning mechanismhas the advantages of high stability and no friction,In some field of precise positioning,integrated fully flexible parallel positioning mechanism has been unable to meet the accuracy requirements. A new mechanism which is called 3-RPC fully compliant parallel positioning mechanism is designed by the topology optimization design theory. The design of such a new model is based on the configuration and motion characteristics of a 3-RPC integrated fully compliant positioning mechanism. Firstly,taking the 3-RPC parallel positioning mechanism as the research object,the mapping relationship between the input and output is solved by the micro displacement method.Secondly,The model of 3-RPC integrated fully compliant positioning mechanism and 3-RPC fully compliant parallel positioning mechanismare designed. Finally,the static and dynamic analysis of two positioning mechanisms was carried out by the finite element software. The results show that the location accuracy and vibration resistance of 3-RPC fully compliant parallel positioning mechanism are better than its prototype.