提出一种单支链含闭环五杆结构单元的新型3-5RS并联机构,该机构结构简单,求解容易。利用封闭矢量环法计算位置正反解,基于杆长约束方程求导得到了速度以及加速度输入输出方程,建立速度雅可比矩阵。给出机构在一般构型下的工作空间,基于雅可比矩阵分析了机构的静刚度,结果显示该机构相比于支链为开环结构的3-RRS并联机构,其刚度性能明显提高。针对工业生产中的连续直线加工任务进行轨迹规划,仿真结果验证了理论计算和模型建立的正确性以及机构实现运动的能力。
A novel 3-5RS parallel mechanism which has five-bar close-loop structure links is proposed due to its simple structure and easy solution. Closed-vector-circle method is used to solve the forward and inverse kinematic solution of the mechanism. Speed and acceleration of input and output equation are deduced by link constraint equation derivation. The workspace of the parallel mechanism in a general configuration is given. Stiffness performance is analyzed based on Jacobian matrix. Compared with 3-RRS parallel mechanism, the results show that the stiffness performance of the mechanism is improved obviously. The trajectory planning of continuous linear processing tasks in industrial production is carded out, the simulation results verify the theoretical calculation and model establishment are correct and the ability of the mechanism to implement motion.