Determination of Singularity Occurrence and Characteristic Analysis of Dual 6-DOF Manipulator Using Manipulability and Manipulability Ellipsoid

In this paper, we judge whether the singularity occurs among the path of dual 6-DOF manipulator using manipulability and analyze the characteristics in the velocity space of the straight path and alternative path what avoids the singularity using manipulability ellipsoid. To do this, we solved the inverse kinematics of the manipulator and made simulator in MATLAB. In this simulator, the path can be set in advance and change of manipulability and manipulability ellipsoid can be observed. This allows better path to be determined in advance before following it. Experiments has confirmed that singularity occurs in straight path and eigenvalue in the direction of yaw is zero. In addition, the alternative path is identified as an improved path due to the large eigenvalue in the direction of pitch and yaw. Since this result can be used as an indicator for evaluating the agent's state, we intend to apply to reinforcement learning and research to create a singularity avoidance path by the robot itself.