四川轻化工大学学报：自然科学版

机械臂在工程应用中，路径点的位姿约束会影响关节冲击，从而影响机械臂作业的轨迹精度。针对“3-5-3”关节空间轨迹插值和三次、四次混合式插值等算法在实际应用中出现的关节冲击问题，通过分析多项式插值特性，提出了“5-7-5”混合插值算法。以路径分段为前提，交替应用五次与七次多项式进行关节位姿插值计算，降低机械臂关节在关键路径点处的位姿参数变化速率。以六自由度机械臂Puma560为研究对象，利用MATLAB平台建立Puma560仿真模型，并以机械臂在A、B两点完成循环搬运的运动方式为运动场景，通过混合插值算法计算6个关节的位姿变化情况，分析角度、角速度、角加速度随时间的变化规律，并与“3-5-3”、“3-4-3”等插值算法进行对比。结果表明，机械臂关节运动轨迹通过“5-7-5”混合插值算法优化后的位姿曲线连续、平滑，能有效降低关节冲击，为关节空间轨迹规划提供一种以降低关节冲击为目标的优化方法.

In the engineering application of the manipulator, the position and pose constraint of the path point will affect the impact of the joint, thus affecting the trajectory precision of the manipulator. Aiming at the joint impact problem caused by the application of “3-5-3” joint space trajectory interpolation and three-and fourtimes mixed interpolation algorithm, a “5-7-5” hybrid interpolation algorithm is proposed by analyzing the polynomial interpolation characteristics, which alternately applies the five-time and seventh-order polynomials to calculate the joint pose interpolation on the premise of path segmentation, reduce the rate of change of the pose parameters of the robotic arm joints at critical path points. Taking the six-degree-of-freedom manipulator Puma560 as the research object, the Puma560 simulation model is established by using MATLAB platforms, and the movement mode of the manipulator completing the cyclic transportation at points A and B is taken as the motion scene, and the pose changes of the six joints are calculated by the hybrid interpolation algorithm, the variation of angle, angular velocity and angular acceleration with time is analyzed, and compared with with“3-5-3”, “3-4-3” and other interpolation algorithms. The results show that the joint trajectory of the manipulator is continuous and smooth after being optimized by the “5-7-5” hybrid interpolation algorithm, which can effectively reduce the joint impact. This paper provides an optimization method for joint space trajectory planning with the goal of reducing joint impact.