六自由度并联平台具有结构刚度好、承载能力大、控制精度高等优点,被广泛应用于军工装备、航天航空、制造业等领域。但它也存在固有的缺点,如工作空间小,容易产生运动干涉和奇异位形等。为克服上述缺点对设计的影响,在有限的排布空间内,通过采用分段组合法分析和穷举法迭代,结合运动学和动力学仿真,对结构优化和机构受力展开研究,有效改善了边界条件限制下的机构运动范围、定位精度和变形情况,提高了六自由度并联平台的综合性能。该系统在工件需要自动化对接的场合具有广泛的应用前景。

The Stewart parallel platform with 6 degree of freedoms (6-DOFS), which has the advantages of big bearing capacity,high control accuracy and strong structure stiffness, has been widely used in military equipment, astronautics and industry applications.Meanwhile, its inherent defects, such as small workspace, poor dexterity and the singularity configurations, have constrained its further application. In this paper structure optimization and force analysis were carried out based on kinematics and dynamic simulation results using enumeration method, to improve the positioning accuracy, structure stiffness and expend the workspace under constrained boundary condition. Finally, the inherent defects could be resolved and the comprehensive performance could be improved, and thus the system could be further used in automatic docking applications.

TH137