Implementation of twisting skill to robot hands for manipulating linear deformable objects


This paper describes the implementation of a twisting skill to a multi-DOF end effector for manipulating linear deformable objects (LDOs). When manipulating of LDOs such as rope knotting, an important factor is to control torsion. However, controlling torsion is difficult using only the robot arm movement because of the range limit of a manipulator and the danger of collision with the environment such as a table and objects to be tied. On the other hand, implementing the movement into a robot hand as in-hand manipulation means that the robot-arm movement can be compact. In this study, we extract what is needed in a “twisting skill”, implement them into multi-DOF end effectors mounted on a dual-arm robot, and evaluate the skill. Then, we demonstrate rope manipulation including a knotting task and verify the effect by using a twisting skill. Our results show that the proposed method can be used to control the twisted angle of the rope with the required precision. Furthermore, using the proposed twisting skill, when placing a rope on a table top, the accuracy and reproducibility are improved compared with the case when the skill is not used. Finally, using the proposed method, clove hitches are successfully tied.

2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)