OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI

Abstract Background FES-Cycling is an exciting recreational activity, which allows certain individuals after spinal cord injury or stroke to exercise their paralyzed muscles. The key for a successful application is to activate the right muscles at the right time. Methods While a stimulation pattern...

Full description

Bibliographic Details
Main Authors: Martin Schmoll, Ronan Le Guillou, Charles Fattal, Christine Azevedo Coste
Format: Article
Language:English
Published: BMC 2022-04-01
Series:Journal of NeuroEngineering and Rehabilitation
Subjects:
Online Access:https://doi.org/10.1186/s12984-022-01018-2
_version_ 1818273507977461760
author Martin Schmoll
Ronan Le Guillou
Charles Fattal
Christine Azevedo Coste
author_facet Martin Schmoll
Ronan Le Guillou
Charles Fattal
Christine Azevedo Coste
author_sort Martin Schmoll
collection DOAJ
description Abstract Background FES-Cycling is an exciting recreational activity, which allows certain individuals after spinal cord injury or stroke to exercise their paralyzed muscles. The key for a successful application is to activate the right muscles at the right time. Methods While a stimulation pattern is usually determined empirically, we propose an approach using the torque feedback provided by a commercially available crank power-meter installed on a standard trike modified for FES-Cycling. By analysing the difference between active (with stimulation) and passive (without stimulation) torques along a full pedalling cycle, it is possible to differentiate between contributing and resisting phases for a particular muscle group. In this article we present an algorithm for the detection of optimal stimulation intervals and demonstrate its functionality, bilaterally for the quadriceps and hamstring muscles, in one subject with complete SCI on a home trainer. Stimulation patterns were automatically determined for two sensor input modalities: the crank-angle and a normalized thigh-angle (i.e. cycling phase, measured via inertial measurement units). In contrast to previous studies detecting automatic stimulation intervals on motorised ergo-cycles, our approach does not rely on a constant angular velocity provided by a motor, thus being applicable to the domain of mobile FES-Cycling. Results The algorithm was successfully able to identify stimulation intervals, individually for the subject’s left and right quadriceps and hamstring muscles. Smooth cycling was achieved without further adaptation, for both input signals (i.e. crank-angle and normalized thigh-angle). Conclusion The automatic determination of stimulation patterns, on basis of the positive net-torque generated during electrical stimulation, can help to reduce the duration of the initial fitting phase and to improve the quality of pedalling during a FES-Cycling session. In contrast to previous works, the presented algorithm does not rely on a constant angular velocity and thus can be effectively implemented into mobile FES-Cycling systems. As each muscle or muscle group is assessed individually, our algorithm can be used to evaluate the efficiency of novel electrode configurations and thus could promote increased performances during FES-Cycling.
first_indexed 2024-12-12T21:59:04Z
format Article
id doaj.art-b494c17b5c9c4309a854cf4586a81e71
institution Directory Open Access Journal
issn 1743-0003
language English
last_indexed 2024-12-12T21:59:04Z
publishDate 2022-04-01
publisher BMC
record_format Article
series Journal of NeuroEngineering and Rehabilitation
spelling doaj.art-b494c17b5c9c4309a854cf4586a81e712022-12-22T00:10:34ZengBMCJournal of NeuroEngineering and Rehabilitation1743-00032022-04-0119111210.1186/s12984-022-01018-2OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCIMartin Schmoll0Ronan Le Guillou1Charles Fattal2Christine Azevedo Coste3INRIA-Université de MontpellierINRIA-Université de MontpellierRehabilitation Center Bouffard VercelliINRIA-Université de MontpellierAbstract Background FES-Cycling is an exciting recreational activity, which allows certain individuals after spinal cord injury or stroke to exercise their paralyzed muscles. The key for a successful application is to activate the right muscles at the right time. Methods While a stimulation pattern is usually determined empirically, we propose an approach using the torque feedback provided by a commercially available crank power-meter installed on a standard trike modified for FES-Cycling. By analysing the difference between active (with stimulation) and passive (without stimulation) torques along a full pedalling cycle, it is possible to differentiate between contributing and resisting phases for a particular muscle group. In this article we present an algorithm for the detection of optimal stimulation intervals and demonstrate its functionality, bilaterally for the quadriceps and hamstring muscles, in one subject with complete SCI on a home trainer. Stimulation patterns were automatically determined for two sensor input modalities: the crank-angle and a normalized thigh-angle (i.e. cycling phase, measured via inertial measurement units). In contrast to previous studies detecting automatic stimulation intervals on motorised ergo-cycles, our approach does not rely on a constant angular velocity provided by a motor, thus being applicable to the domain of mobile FES-Cycling. Results The algorithm was successfully able to identify stimulation intervals, individually for the subject’s left and right quadriceps and hamstring muscles. Smooth cycling was achieved without further adaptation, for both input signals (i.e. crank-angle and normalized thigh-angle). Conclusion The automatic determination of stimulation patterns, on basis of the positive net-torque generated during electrical stimulation, can help to reduce the duration of the initial fitting phase and to improve the quality of pedalling during a FES-Cycling session. In contrast to previous works, the presented algorithm does not rely on a constant angular velocity and thus can be effectively implemented into mobile FES-Cycling systems. As each muscle or muscle group is assessed individually, our algorithm can be used to evaluate the efficiency of novel electrode configurations and thus could promote increased performances during FES-Cycling.https://doi.org/10.1186/s12984-022-01018-2Functional electrical stimulation (FES)FES-CyclingCybathlonSpinal cord injuryFES-SportsInertial measurement unit (IMU)
spellingShingle Martin Schmoll
Ronan Le Guillou
Charles Fattal
Christine Azevedo Coste
OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI
Journal of NeuroEngineering and Rehabilitation
Functional electrical stimulation (FES)
FES-Cycling
Cybathlon
Spinal cord injury
FES-Sports
Inertial measurement unit (IMU)
title OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI
title_full OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI
title_fullStr OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI
title_full_unstemmed OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI
title_short OIDA: An optimal interval detection algorithm for automatized determination of stimulation patterns for FES-Cycling in individuals with SCI
title_sort oida an optimal interval detection algorithm for automatized determination of stimulation patterns for fes cycling in individuals with sci
topic Functional electrical stimulation (FES)
FES-Cycling
Cybathlon
Spinal cord injury
FES-Sports
Inertial measurement unit (IMU)
url https://doi.org/10.1186/s12984-022-01018-2
work_keys_str_mv AT martinschmoll oidaanoptimalintervaldetectionalgorithmforautomatizeddeterminationofstimulationpatternsforfescyclinginindividualswithsci
AT ronanleguillou oidaanoptimalintervaldetectionalgorithmforautomatizeddeterminationofstimulationpatternsforfescyclinginindividualswithsci
AT charlesfattal oidaanoptimalintervaldetectionalgorithmforautomatizeddeterminationofstimulationpatternsforfescyclinginindividualswithsci
AT christineazevedocoste oidaanoptimalintervaldetectionalgorithmforautomatizeddeterminationofstimulationpatternsforfescyclinginindividualswithsci