TY - GEN
T1 - Tank based unified torque/impedance control for a pneumatically actuated antagonistic robot joint
AU - Toedtheide, Alexander
AU - Shahriari, Erfan
AU - Haddadin, Sami
N1 - Publisher Copyright:
© 2017 IEEE.
PY - 2017/7/21
Y1 - 2017/7/21
N2 - In this paper the concept of a unified torque/impedance controller is applied to a pneumatically actuated, antagonistic robot joint. The investigated control algorithm consists of a cascaded structure in which the outer torque/impedance controller commands a desired torque to two cylinder-based force controllers. The torque-/impedance controller is equipped with a virtual tank that ensures passivity of the control loops above force level. Additionally, a shaping function provides a continuous transition to impedance control in case of sudden contact loss during a torque control operation. External torques used in the feedback loop for contact force regulation are estimated by a momentum observer. Experimental and simulation results show a maximum deflection of 9.7° over 130 ms in case of contact loss until a resting position is reached. Additionally, step and sinusoidal torque tracking up to 5 Hz was successfully tested at good performance.
AB - In this paper the concept of a unified torque/impedance controller is applied to a pneumatically actuated, antagonistic robot joint. The investigated control algorithm consists of a cascaded structure in which the outer torque/impedance controller commands a desired torque to two cylinder-based force controllers. The torque-/impedance controller is equipped with a virtual tank that ensures passivity of the control loops above force level. Additionally, a shaping function provides a continuous transition to impedance control in case of sudden contact loss during a torque control operation. External torques used in the feedback loop for contact force regulation are estimated by a momentum observer. Experimental and simulation results show a maximum deflection of 9.7° over 130 ms in case of contact loss until a resting position is reached. Additionally, step and sinusoidal torque tracking up to 5 Hz was successfully tested at good performance.
KW - compliance and impedance control
KW - hydraulic/pneumatic actuators
KW - tendon/wire mechanism
UR - http://www.scopus.com/inward/record.url?scp=85027959874&partnerID=8YFLogxK
U2 - 10.1109/ICRA.2017.7989149
DO - 10.1109/ICRA.2017.7989149
M3 - Conference contribution
AN - SCOPUS:85027959874
T3 - Proceedings - IEEE International Conference on Robotics and Automation
SP - 1255
EP - 1262
BT - ICRA 2017 - IEEE International Conference on Robotics and Automation
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2017 IEEE International Conference on Robotics and Automation, ICRA 2017
Y2 - 29 May 2017 through 3 June 2017
ER -