油茶果动态抓取Delta机器人正运动学特性研究

Forward Kinematics Characteristics of Camellia Fruit Dynamically Grasping Delta Robot Based on Screw Theory

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)2Delta机器人正运动学方程的方法。针对3-R(SS)2Delta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 equation and the measured values of Delta robot test platform are compared and analyzed.The position error of the end-effector 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.