TY - JOUR
T1 - LIMPACT:A Hydraulically Powered Self-Aligning Upper Limb Exoskeleton
AU - Otten, Alexander
AU - Voort, Hendrik Carsten
AU - Stienen, Arno
AU - Aarts, Ronald G.K.M.
AU - van Asseldonk, Edwin H.F.
AU - van der Kooij, Herman
PY - 2015
Y1 - 2015
N2 - The LIMPACT is an exoskeleton developed to be used in identifying the reflex properties of the arm in stroke survivors. Information on joint reflexes helps in designing optimal patient specific therapy programs. The LIMPACT is dynamically transparent by combining a lightweight skeleton with high power to weight ratio actuators. The LIMPACT is supported by a passive weight balancing mechanism to compensate for the weight of the exoskeleton and the human arm. Various self-aligning mechanisms allow the human joint axes to align with the axes of the exoskeleton which ensure safety and short don/doff times. The torque-controlled motors have a maximum torque bandwidth of 97 Hz which is required for fast torque perturbations and smooth zero impedance control. The LIMPACT's weight is reduced five times as gravitational forces are lowered using a model-based gravity compensation algorithm. The impedance controller ensures tracking of a cycloidal joint angle reference. A cycloid with an amplitude of 1.3 rd and a maximum velocity of 6.5 rd/s has a maximum tracking error of only 7%. The LIMPACT fulfills the requirements to be used in future diagnostics measurements for stroke patients.
AB - The LIMPACT is an exoskeleton developed to be used in identifying the reflex properties of the arm in stroke survivors. Information on joint reflexes helps in designing optimal patient specific therapy programs. The LIMPACT is dynamically transparent by combining a lightweight skeleton with high power to weight ratio actuators. The LIMPACT is supported by a passive weight balancing mechanism to compensate for the weight of the exoskeleton and the human arm. Various self-aligning mechanisms allow the human joint axes to align with the axes of the exoskeleton which ensure safety and short don/doff times. The torque-controlled motors have a maximum torque bandwidth of 97 Hz which is required for fast torque perturbations and smooth zero impedance control. The LIMPACT's weight is reduced five times as gravitational forces are lowered using a model-based gravity compensation algorithm. The impedance controller ensures tracking of a cycloidal joint angle reference. A cycloid with an amplitude of 1.3 rd and a maximum velocity of 6.5 rd/s has a maximum tracking error of only 7%. The LIMPACT fulfills the requirements to be used in future diagnostics measurements for stroke patients.
KW - IR-98213
KW - METIS-311455
U2 - 10.1109/TMECH.2014.2375272
DO - 10.1109/TMECH.2014.2375272
M3 - Article
VL - 20
SP - 2285
EP - 2298
JO - IEEE/ASME transactions on mechatronics
JF - IEEE/ASME transactions on mechatronics
SN - 1083-4435
IS - 5
M1 - 7044558
ER -