A hybrid robot for friction stir welding
A hybrid robot for friction stir welding
复制标题
搅拌摩擦焊混合机器人
DOI：
10.1177/0954406214562848
复制
发表时间：
2015-10-01
影响因子：
2
通讯作者：
Wu, Chuanyu
中科院分区：
文献类型：
--
作者：
Li, Qinchuan;Wu, Weifeng;Wu, Chuanyu
搅拌摩擦焊（FSW）代替传统的熔焊在许多领域得到了广泛的应用。然而，需要巨大的轴向向下力来维持稳定的焊接过程。此外，沿着曲面焊接的任务需要定向能力，这是传统FSW机器不能提供的。为了克服这一限制，我们提出了一个5轴混合机器人搅拌摩擦焊。该混联机器人由一个2-SPR-RPS并联机构（具有一个平移自由度和两个转动自由度）和两个龙门架组成。首先，利用螺旋理论分析了并联机构在初始和一般构型下的自由度，确定了连续转动轴。其次，研究了混联机器人的位置正解和逆解，得到了并联机构的雅可比矩阵。通过分析运动/力传递率，优化了并联机构的结构参数。最后，考虑驱动杆、关节角度和奇异位形的约束，得到了末端执行器的可达工作空间。
Friction stir welding (FSW) has been widely applied in a number of fields instead of traditional fusion welding. However, a huge axial downward force is required to maintain a steady welding process. Moreover, the task of welding along a curved surface requires an orientation ability, which traditional FSW machines cannot provide. To overcome this limitation, we propose a 5-axis hybrid robot for FSW. This hybrid robot comprises a 2-SPR-RPS parallel mechanism (with one translational degree of freedom and two rotational degrees of freedom) and two gantries. First, mobility of the parallel mechanism in the initial and general configuration is analyzed using screw theory and continuous rotational axes are identified. Second, forward and inverse position solutions to the hybrid robot are studied, and the Jacobian matrix of the parallel mechanism is obtained. By analyzing the motion/force transmissibility, the architectural parameters of the parallel mechanism are optimized. Finally, the reachable workspace of the end effector is obtained considering the constraints of actuation links, joint angles, and singular configuration.