一种基于角度传感器的6-UPS机构正向运动学分析方法

为了提高6自由度并联机构运动学正解的求解效率,增强求解方法的通用性,提出了一种6-UPS(universal-prismatic-spherical)机构的运动学正解算法.首先在6-UPS机构任意分支虎克铰处添加2个角度传感器,测量了虎克铰2个方位的旋转角度.再基于旋转矩阵构建12个方程,通过代数消元对其进行降次处理得到简易的一元二次方程组.最后,求得6-UPS机构的运动学正解.并通过具体数值算例验证所提方法,求出了确定的位置正解.该方法不仅降低了数据处理的难度,且能求得正解的唯一解,避免了并联机构正解存在多解的问题.

A Method for Forward Kinematics Analysis of 6-UPS Mechanism Based on Angle Sensor

In order to improve the efficiency and universality of the forward kinematics solution of six-degree-of-freedom parallel mechanisms, a forward kinematics solution algorithm of 6-UPS (universal-prismatic-spherical) mechanism is proposed. Firstly, two angle sensors are added to the Hook hinge of any branch of the 6-UPS mechanism, and the rotation angles in the two directions of the Hook hinge are measured. Then 12 equations are constructed based on the rotation matrix, and a simple one-variant quadratic equation system is obtained by reducing the order of equation through algebraic elimination. Finally, the forward kinematics solution of the 6-UPS mechanism is obtained. The proposed method is verified by the numerical examples, and the definite forward kinematics solution is obtained. The method not only reduces the difficulty of data processing, but also solves a unique forward solution, and therefore the problem is avoided that there are multiple forward solutions in parallel mechanism.