针对传统 D-H 参数法求解机械臂运动学时过程比较复杂的问题,为满足油茶果动态抓取的要求,提出了一种基于旋量理论构建 3-R(SS)2 Delta 机器人正运动学方程的方法.针对 3-R(SS)2 Delta 机器人的结构进行分析;通过旋量理论的指数积公式对该机器人的正运动学特性进行研究,获得机器人的位姿变换矩阵;最后,通过搭建的 Delta 机器人试验平台运行标准门型轨迹,结果表明:Delta 机器人末端执行器能够精准地对传送带上移动的油茶果进行抓取.对比分析正运动学方程的计算值和 Delta 机器人试验平台试验测量值,得到末端执行器位置值的位置误差为±0.3mm,验证了所提出方法对构建油茶果动态抓取 Delta 机器人正运动学方程的正确性及可行性,旨在为后续进行油茶果动态抓取的轨迹规划研究奠定基础.
In order to meet the requirements of dynamic grasping of camellia camellia fruit,a forward kinematics equation of 3-R(SS)Delta robot was proposed based on screw theory to solve the complicated kinematic process of manipulator with traditional D-H parameter method.The structure of 3-R(SS)Delta robot is analyzed.Based on screw theory and exponential product formula,the forward kinematics of the robot was analyzed,and the pose transformation matrix of the robot was obtained.Finally,the Delta robot end-effector can accurately grab the camellia fruit moving on the conveyor belt by running the standard gate trajectory of the built Delta robot test platform.The calculated values of forward kinematics e-quation and the measured values of Delta robot test platform are compared and analyzed.The position error of the end-ef-fector position value is±0.01mm,which verifies the correctness and feasibility of the proposed method for constructing the forward kinematics equation of 3-R(SS)Delta robot.It lays a foundation for the follow-up research of trajectory planning of dynamic positioning.