Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions

Stationary motorized cycling assisted by functional electrical stimulation (FES) is a popular therapy for people with movement impairments. Maximizing volitional contributions from the rider of the cycle can lead to long-term benefits like increased muscular strength and cardiovascular endurance. Th...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Axton Isaly, Brendon C. Allen, Ricardo G. Sanfelice, Warren E. Dixon
Formato:	article
Lenguaje:	EN
Publicado:	Frontiers Media S.A. 2021
Materias:	functional electrical stimulation (FES ) cycling barrier function safety-critical euler-Lagrange control design Mechanical engineering and machinery TJ1-1570 Electronic computers. Computer science QA75.5-76.95
Acceso en línea:	https://doaj.org/article/c94bfb9e9bb3424fbef010997ae73ae0
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:c94bfb9e9bb3424fbef010997ae73ae0
record_format	dspace
spelling	oai:doaj.org-article:c94bfb9e9bb3424fbef010997ae73ae02021-11-30T18:27:37ZEncouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions2296-914410.3389/frobt.2021.742986https://doaj.org/article/c94bfb9e9bb3424fbef010997ae73ae02021-11-01T00:00:00Zhttps://www.frontiersin.org/articles/10.3389/frobt.2021.742986/fullhttps://doaj.org/toc/2296-9144Stationary motorized cycling assisted by functional electrical stimulation (FES) is a popular therapy for people with movement impairments. Maximizing volitional contributions from the rider of the cycle can lead to long-term benefits like increased muscular strength and cardiovascular endurance. This paper develops a combined motor and FES control system that tasks the rider with maintaining their cadence near a target point using their own volition, while assistance or resistance is applied gradually as their cadence approaches the lower or upper boundary, respectively, of a user-defined safe range. Safety-ensuring barrier functions are used to guarantee that the rider’s cadence is constrained to the safe range, while minimal assistance is provided within the range to maximize effort by the rider. FES stimulation is applied before electric motor assistance to further increase power output from the rider. To account for uncertain dynamics, barrier function methods are combined with robust control tools from Lyapunov theory to develop controllers that guarantee safety in the worst-case. Because of the intermittent nature of FES stimulation, the closed-loop system is modeled as a hybrid system to certify that the set of states for which the cadence is in the safe range is asymptotically stable. The performance of the developed control method is demonstrated experimentally on five participants. The barrier function controller constrained the riders’ cadence in a range of 50 ± 5 RPM with an average cadence standard deviation of 1.4 RPM for a protocol where cadence with minimal variance was prioritized and used minimal assistance from the motor (4.1% of trial duration) in a separate protocol where power output from the rider was prioritized.Axton IsalyBrendon C. AllenRicardo G. SanfeliceWarren E. DixonFrontiers Media S.A.articlefunctional electrical stimulation (FES) cyclingbarrier functionsafety-criticaleuler-Lagrangecontrol designMechanical engineering and machineryTJ1-1570Electronic computers. Computer scienceQA75.5-76.95ENFrontiers in Robotics and AI, Vol 8 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	functional electrical stimulation (FES ) cycling barrier function safety-critical euler-Lagrange control design Mechanical engineering and machinery TJ1-1570 Electronic computers. Computer science QA75.5-76.95
spellingShingle	functional electrical stimulation (FES ) cycling barrier function safety-critical euler-Lagrange control design Mechanical engineering and machinery TJ1-1570 Electronic computers. Computer science QA75.5-76.95 Axton Isaly Brendon C. Allen Ricardo G. Sanfelice Warren E. Dixon Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions
description	Stationary motorized cycling assisted by functional electrical stimulation (FES) is a popular therapy for people with movement impairments. Maximizing volitional contributions from the rider of the cycle can lead to long-term benefits like increased muscular strength and cardiovascular endurance. This paper develops a combined motor and FES control system that tasks the rider with maintaining their cadence near a target point using their own volition, while assistance or resistance is applied gradually as their cadence approaches the lower or upper boundary, respectively, of a user-defined safe range. Safety-ensuring barrier functions are used to guarantee that the rider’s cadence is constrained to the safe range, while minimal assistance is provided within the range to maximize effort by the rider. FES stimulation is applied before electric motor assistance to further increase power output from the rider. To account for uncertain dynamics, barrier function methods are combined with robust control tools from Lyapunov theory to develop controllers that guarantee safety in the worst-case. Because of the intermittent nature of FES stimulation, the closed-loop system is modeled as a hybrid system to certify that the set of states for which the cadence is in the safe range is asymptotically stable. The performance of the developed control method is demonstrated experimentally on five participants. The barrier function controller constrained the riders’ cadence in a range of 50 ± 5 RPM with an average cadence standard deviation of 1.4 RPM for a protocol where cadence with minimal variance was prioritized and used minimal assistance from the motor (4.1% of trial duration) in a separate protocol where power output from the rider was prioritized.
format	article
author	Axton Isaly Brendon C. Allen Ricardo G. Sanfelice Warren E. Dixon
author_facet	Axton Isaly Brendon C. Allen Ricardo G. Sanfelice Warren E. Dixon
author_sort	Axton Isaly
title	Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions
title_short	Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions
title_full	Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions
title_fullStr	Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions
title_full_unstemmed	Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions
title_sort	encouraging volitional pedaling in functional electrical stimulation-assisted cycling using barrier functions
publisher	Frontiers Media S.A.
publishDate	2021
url	https://doaj.org/article/c94bfb9e9bb3424fbef010997ae73ae0
work_keys_str_mv	AT axtonisaly encouragingvolitionalpedalinginfunctionalelectricalstimulationassistedcyclingusingbarrierfunctions AT brendoncallen encouragingvolitionalpedalinginfunctionalelectricalstimulationassistedcyclingusingbarrierfunctions AT ricardogsanfelice encouragingvolitionalpedalinginfunctionalelectricalstimulationassistedcyclingusingbarrierfunctions AT warrenedixon encouragingvolitionalpedalinginfunctionalelectricalstimulationassistedcyclingusingbarrierfunctions
_version_	1718406408916959232

Encouraging Volitional Pedaling in Functional Electrical Stimulation-Assisted Cycling Using Barrier Functions

Ejemplares similares