一种并联机器人轨迹规划算法研究  

Research on Trajectory Planning Algorithm of Parallel Robot

作　　者：朱大昌[1] 盘意华 杜宝林 吴光毅 谢清华 ZHU Dachang;PAN Yihua;DU Baolin;WU Guangyi;XIE Qinghua(School of Mechanical and Electrical Engineering,Guangzhou University,Guangzhou Guangdong 510006,China)

机构地区：[1]广州大学机械与电气工程学院,广东广州510006

出　　处：《机床与液压》2023年第5期14-22,共9页Machine Tool & Hydraulics

基　　金：广州大学研究生创新研究资助计划项目(2021GDJC-M31);国家自然科学基金资助项目(51905115)。

摘　　要：针对并联机器人工作空间微小线段间拐角处产生的冲击与振动问题,提出一种基于笛卡尔空间与关节空间相结合的机器人联合空间轨迹规划方法。在笛卡尔空间中采用三次非均匀有理B样条曲线对机器人末端执行器复杂的加工轨迹进行插补。为解决笛卡尔空间微小线段间拐角处的切向不连续导致轨迹突变的问题,基于并联机器人逆运动学模型,将笛卡尔空间轨迹规划算法所得插补点映射到关节空间,采取五次均匀B样条曲线进行第二次轨迹插补,平滑并联机器人运动过程中加速度及加加速度突变曲线。并在动力学层面验证所提算法的有效性。仿真结果表明:联合空间轨迹规划策略能使机器人末端执行器较好地改善连续高阶曲率导数的轨迹平滑问题,提高末端跟踪精度。实验结果表明:末端跟踪误差值最大减少21.12%,力矩最大值减少11.65%。Aiming at the problem of impact and vibration at the corner between micro segments in the workspace of parallel robot,a joint-space trajectory planning method based on Cartesian space and joint space was proposed.In essence,the complex machining trajectory of robot is to approximate the target curve by using small straight line segments.The cubic non-uniform rational B-splines(NURBS)curve was used to interpolate the complex machining trajectory of the end effector in robot Cartesian space.In order to solve the problem of sudden change of trajectory caused by tangential discontinuity at the corner between small line segments in Cartesian space,based on the inverse kinematics model of the parallel robot,the interpolation points obtained by the Cartesian space trajectory planning algorithm were mapped to the joint space,and the quintic uniform B-spline curve was used for the second trajectory interpolation in the joint space,smoothing the abrupt curves of acceleration and jerk during the movement of the parallel robot.Finally,the effectiveness of the proposed algorithm was verified at the dynamic level.The simulation results show that the joint spatial trajectory planning strategy can be used to make the robot end effector better improve the trajectory smoothing problem caused by continuous high-order curvature derivatives and improve the end tracking accuracy.The experimental results show that the end tracking error is reduced by 21.12%and the maximum torque is reduced by 11.65%.

关 键 词：并联机器人 联合空间轨迹规划算法 NURBS 五次均匀B样条 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置]