Impedance control of a series elastic drive system added with another actuator

As a driving source of a robot arm in order to achieve a smooth movement at high power and with a minimal size, a series elastic drive system added with another actuator is used in this research. A series elastic mechanism using a torsion bar and a high reduction actuator drives the arm, and the added low reduction actuator reduces the vibration characteristics of the arm according to the response delay of the high-reduction actuator and the elastic system. In order to drive the proposed mechanism described above in low impedance, an impedance control method was adapted to the system. From the results of the simulations and experiments, compared to the response of traditional series elastic driving system and the proposed system, we showed the effectiveness of our proposed system.