Motion Control Strategy for Redundant Visual Tracking Mechanism of a Humanoid Robot

Visual target tracking is one of the main functions that interacting with the environment for the humanoid robot, and it is also an important embodiment of anthropomorphism and human likeness. In order to achieve dexterous and precise visual target tracking task, a kind of humanoid robot head mechanism which is similar to the human head is presented. By using of the modeling method of virtual link, the control task of robot visual tracking is converted to the inverse kinematics solution of a 4DOF RRRP manipulator, and the solution is obtained based on the damped least-squares method. In order to make the manipulator avoid the singularity and joint limit synchronously, a new method for calculating the damping factor is proposed. On the basis of the traditional damping factor which is mainly used to hinder the manipulator close to the singular configuration, the damping factor that hinders the manipulator close to the joint limit is also proposed, and the total damping factor is composed of the two parts. Simulation and analysis show that the redundant visual tracking mechanism can track a moving target stably and precisely.