TY - JOUR
T1 - Center of mass acceleration feedback control of standing balance by functional neuromuscular stimulation against external postural perturbations
AU - Nataraj, Raviraj
AU - Audu, Musa L.
AU - Triolo, Ronald J.
PY - 2013
Y1 - 2013
N2 - This study investigated the use of center of mass (COM) acceleration feedback for improving performance of a functional neuromuscular stimulation control system to restore standing function to a subject with complete, thoracic-level spinal cord injury. The approach for linearly relating changes in muscle stimulation to changes in COM acceleration was verified experimentally and subsequently produced data to create an input-output map driven by sensor feedback. The feedback gains were systematically tuned to reduce upper extremity (UE) loads applied to an instrumented support device while resisting external postural disturbances. Total body COM acceleration was accurately estimated (>89% variance explained) using 3-D outputs of two accelerometers mounted on the pelvis and torso. Compared to constant muscle stimulation employed clinically, feedback control of stimulation reduced UE loading by 33%. COM acceleration feedback is advantageous in constructing a standing neuroprosthesis since it provides the basis for a comprehensive control synergy about a global, dynamic variable and requires minimal instrumentation. Future work should include tuning and testing the feedback control system during functional reaching activity that is more indicative of activities of daily living.
AB - This study investigated the use of center of mass (COM) acceleration feedback for improving performance of a functional neuromuscular stimulation control system to restore standing function to a subject with complete, thoracic-level spinal cord injury. The approach for linearly relating changes in muscle stimulation to changes in COM acceleration was verified experimentally and subsequently produced data to create an input-output map driven by sensor feedback. The feedback gains were systematically tuned to reduce upper extremity (UE) loads applied to an instrumented support device while resisting external postural disturbances. Total body COM acceleration was accurately estimated (>89% variance explained) using 3-D outputs of two accelerometers mounted on the pelvis and torso. Compared to constant muscle stimulation employed clinically, feedback control of stimulation reduced UE loading by 33%. COM acceleration feedback is advantageous in constructing a standing neuroprosthesis since it provides the basis for a comprehensive control synergy about a global, dynamic variable and requires minimal instrumentation. Future work should include tuning and testing the feedback control system during functional reaching activity that is more indicative of activities of daily living.
KW - Functional neuromuscular stimulation (FNS)
KW - rehabilitation
KW - spinal cord injury (SCI)
KW - standing balance
UR - http://www.scopus.com/inward/record.url?scp=84871731861&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84871731861&partnerID=8YFLogxK
U2 - 10.1109/TBME.2012.2218601
DO - 10.1109/TBME.2012.2218601
M3 - Article
C2 - 22987499
AN - SCOPUS:84871731861
SN - 0018-9294
VL - 60
SP - 10
EP - 19
JO - IEEE Transactions on Biomedical Engineering
JF - IEEE Transactions on Biomedical Engineering
IS - 1
M1 - 6301683
ER -