2-P_((4R))RR并联机构的工作空间分析与机构参数设计

Workspace analysis and mechanism parameter design for 2-P_((4R))RR parallel mechanism

并联机构在高承载能力、高刚度和高精度等应用场合得到广泛应用.提出一种三自由度2-P4R RR平面冗余驱动并联机构,建立机构的位置方程和速度方程,并利用位置方程绘制机构的工作空间,讨论机构参数的变化对工作空间形状的影响.利用空间模型理论,将机构参数无量纲化,得到机构参数的设计空间,在设计空间内讨论了无量纲化机构参数的变化对工作空间的影响,为2-P4R RR并联机构基于工作空间的机构参数设计提供有效途径.

Parallel mechanisms are wildly used in conditions where large payload capability, high stiffness and fine precision are needed. In the paper, a 3-DOF planar 2-P4R RR parallel mechanism with redundant actuators is proposed, and its position and velocity equations are built. By the aid of the position equations, the workspace of the mechanism is obtained, and the relationship between the shape of the workspace and the mechanism parameters is discussed. Using the physical model of the solution space, the mechanism parameters get dimensionless and design space for the dimensionless parameters is constructed. In the design space, the relationship between the shape of the workspace and the dimensionless parameters is denoted. The research is an effective way to design the mechanism parameters based on the workspce for the 2-P4R RR parallel mechanism.