Implementation of Object Grasping Control for a Robot Arm Using Fuzzy Control and Two-CCD Imaging Measurements

An implementation of an object grasping control system for a robot arm is presented in this paper. The hardware of the system contains a fabricated robot arm with a gripper, a pair of charge-coupled device (CCD) cameras, and a computer as the control center. The two CCD cameras are used to “see” the target object and the two-eye imaging geometry is used to calculate the target’s position in 3-D space. In the control process, the inverse-kinematics (IK) concept is utilized to drive the robot arm. First let the robot arm reach a point round the target object such that the target object locates inside the effective grasping region. A fuzzy based object approaching control is proposed then to adjust the gripper position such that the position error between the target object and gripper positions is reduced until the target object position is reached. Thus, the gripper can grasp the target object precisely. Two experimental cases are conducted to demonstrate the effectiveness of the proposed control, in which the target objects are an egg and a bottle, respectively.