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Title: Cadence Tracking for Switched FES Cycling with Unknown Input Delay
Functional electrical stimulation (FES) induced cycling provides a means of therapeutic exercise and functional restoration for people affected by neuromuscular disorders. A challenge in closed-loop FES control of coordinated motion is the presence of a potentially destabilizing input delay between the application of the electrical stimulation and the resulting muscle contraction. Moreover, switching amongst multiple actuators (e.g., between FES control of various muscle groups and a controlled electric motor) presents additional challenges for overall system stability. In this paper, a closed-loop controller is developed to yield exponential cadence tracking, despite an unknown input delay, switching between FES and motor only control, uncertain nonlinear dynamics, and additive disturbances. Lyapunov-Krasovskii functionals are used in a Lyapunov-based stability analysis to ensure exponential convergence for all time.  more » « less
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Author(s) / Creator(s):
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Date Published:
Journal Name:
2019 IEEE 58th Conference on Decision and Control (CDC)
Page Range / eLocation ID:
60 - 65
Medium: X
Sponsoring Org:
National Science Foundation
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