TY - GEN
T1 - Impedance control for variable stiffness mechanisms with nonlinear joint coupling
AU - Wimböck, Thomas
AU - Ott, Christian
AU - Albu-Schäffer, Alin
AU - Kugi, Andreas
AU - Hirzinger, Gerd
PY - 2008
Y1 - 2008
N2 - The current discussion on physical human robot interaction and the related safety aspects, but also the interest of neuro-scientists to validate their hypotheses on human motor skills with bio-mimetic robots, led to a recent revival of tendondriven robots. In this paper, the modeling of tendon-driven elastic systems with nonlinear couplings is recapitulated. A control law is developed that takes the desired joint position and stiffness as input. Therefore, desired motor positions are determined that are commanded to an impedance controller. We give a physical interpretation of the controller. More importantly, a static decoupling of the joint motion and the stiffness variation is given. The combination of active (controller) and passive (mechanical) stiffness is investigated. The controller stiffness is designed according to the desired overall stiffness. A damping design of the impedance controller is included in these considerations. The controller performance is evaluated in simulation.
AB - The current discussion on physical human robot interaction and the related safety aspects, but also the interest of neuro-scientists to validate their hypotheses on human motor skills with bio-mimetic robots, led to a recent revival of tendondriven robots. In this paper, the modeling of tendon-driven elastic systems with nonlinear couplings is recapitulated. A control law is developed that takes the desired joint position and stiffness as input. Therefore, desired motor positions are determined that are commanded to an impedance controller. We give a physical interpretation of the controller. More importantly, a static decoupling of the joint motion and the stiffness variation is given. The combination of active (controller) and passive (mechanical) stiffness is investigated. The controller stiffness is designed according to the desired overall stiffness. A damping design of the impedance controller is included in these considerations. The controller performance is evaluated in simulation.
UR - http://www.scopus.com/inward/record.url?scp=69549101982&partnerID=8YFLogxK
U2 - 10.1109/IROS.2008.4651079
DO - 10.1109/IROS.2008.4651079
M3 - Conference contribution
AN - SCOPUS:69549101982
SN - 9781424420582
T3 - 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS
SP - 3796
EP - 3803
BT - 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS
T2 - 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS
Y2 - 22 September 2008 through 26 September 2008
ER -