6-PPPS正交六自由度并联机构的位置正反解

Forward and Inverse Displacement Analysis of 6-PPPS Orthogonal 6-DOF Parallel Mechanism

针对一种新型6-PPPS并联机构,提出方向余弦阵法进行位置正反解的解析求解。利用机构运动副的运动参数构建并联动平台的方向余弦阵,通过添加约束条件,得到唯一的反解,同样方法可得出所有从动移动副的运动参数。根据方向余弦阵的性质构建约束方程,利用Maple软件辅助求得8组解析正解。根据球铰的约束,发现该机构实际正解唯一,给出了唯一正解的求取方法。

In this paper, a new method for forward and inverse displacement analysis of a new parallel mechanism is proposed based on direction-cosine matrix. A direction-cosine matrix of moving parallel platform is constructed by the motion parameters of a mechanism pair. Unique inverse solution is obtained by the direction-cosine matrix and other constraint equations. In the same way, the motion parameters of slave moving pairs can be obtained. Constraint equations are obtained by the properties of direction-cosine matrix, then eight groups of forward solution can be determined by Maple-aided solution. Unique forward solution is found to exist by the real sphere-hinge constraint, and the method for determining the unique forward solution is given.