Design of an apple-picking end effector

Abstract

A motor-driven end effector with 9 degrees of freedom has been designed. Information of the joint position is transmitted to the potentiometer through gears to realize the position control for the finger joint. The maximum torque of the finger joint motor is verified by imposing a load on the end effector fingertip under the parabola-straight line angular velocity curve. The single-finger coordinate system and the whole-hand coordinate system are established for the end effector through the Denavit-Hartenberg (D-H) method. The forward kinematics and inverse kinematics analysis of the end effector are carried out. To realize the stationary motion of the end effector, the basic algorithms for the starting, stopping and accelerating of the finger joint is designed, based on the analysis of the grasping space using Monte Carlo method and the analysis of the angular displacement of motor using an isochronic interpolation algorithm. The control system is designed based on STM32F103RC to realize the stationary motion of the end effector. Using Tiny 6410, the remote wireless debugging system of the end effector is designed to realize independent control and remote wireless debugging of each joint motor.