Design, Control and Evaluation of a Whole-Sensitive Robot Arm for Physical Human-Robot Interaction

The paper focuses on design and control of a new anthropomorphic robot arm enabling the torque measurement in each joint to ensure safety while performing tasks of physical interaction with human and environment. When the contact of the robot arm with an object occurs, local admittance algorithm provides active compliance of corresponding robot arm joint. Thus, the whole structure of the manipulator can safely interact with an unstructured environment. The detailed design procedure of the 4-DOF robot arm and optical torque sensors is described in the paper. The experimental results of joint admittance control revealed the feasibility of the proposed approach to provide safe interaction of entire structure of robot arm with a person. The control system with load angle position feedback and lead compensator is proposed to improve dynamic behavior of flexible joint arm. The experimental results show high performance of the developed controller in terms of successful damping of vibrations.