Most fully-parallel manipulators encountered today have a common disadvantage, i.e., their low rotational capability. To overcome such a difficulty, this paper focuses its attention on the proposal of a new family of three-degree-of-freedom (3-DoF) fully-parallel manipulators capable of high rotational capability. Parallelogram allows the output link to remain at a fixed orientation with respect to an input link, for which it has many unique roles, especially when creating a desirable DoF output in the design of parallel manipulators. The role of a parallelogram herein described, is used completely for the design of a new parallel manipulator family. In this family, the moving platform of a parallel manipulator is connected to the base by three non-identical legs. The fact that all joints involved in the rotational DoF are with single DoF guarantees the high rotational capability performance of the manipulators. The parallel manipulators proposed here have wide applications in industrial robots, simulators, micro-motion manipulators, parallel kinematics machines, and any other manipulation devices that a high rotational capability is needed. The research provides a new design methodology of novel parallel manipulators. 2004 Elsevier Ltd. All rights reserved.

提出一种新型空间3自由度并联机器人机构，该机器人机构的动平台相对于定平台具有空间2个移动、1个转动自由度。建立了其运动学正反解的封闭形式，并对其工作空同进行了系统的分析和研究。该新型并联机器人机构在工业机器人、薇动机器人、少自由度飞行模拟器和并联机床等领域具有广泛的应用。

The design of the robotic mechanisms is most important because they determine the performance characteristics of the robots. This paper concerns the issue of computer-aided design (CAD) for planar 3-DOF parallel robotic mechanisms by means of the physical model of the solution space, which can be used systematically to express the relationships between the performance criteria and all link lengths of one type of the robtic mechanism. The performance atlases of the workspace volume for the manipulators are plotted in the physical model of the solution space. The characteristics of the distribution of the workspace shapes in the physical model of the solution space are presented. The results are useful for the optimum design of the robotic mechanisms. This paper proposes a new way for robotic CAD.

Parallel manipulators for the machine tool industry have been studied extensively for various industrial applications. However, limited useful workspace areas, the poor mobility, and design difficulties of mote complex parallel manipulators have led to more interest in parallel manipulators with less than six degrees of freedom (Dots). Several parallel mechanisms with various numbers and types of degrees of freedom are described in this paper, which can be used in parallel kinematics machines, motion simulators, and industrial robots

研究一种球坐标式3自由度并联机器人机构的运动学设计，包括运动学反解、速度、考虑铰链转动范围和干涉等条件下的工作空间，和结构参数对工作空间的影响以及灵巧性能指标及其在保角变换平面上的分布特性，这些分析结果和结论对并联机器人机构的设计、轨迹规划和控制等有重要的指导意义并联机构在并联机床、坐标测量机构和工业机器人等领域有广阔的应用前景