TY - GEN
T1 - Design of a soft ankle-foot orthosis exosuit for foot drop assistance
AU - Thalman, Carly M.
AU - Hsu, Joshua
AU - Snyder, Laura
AU - Polygerinos, Panagiotis
PY - 2019/5/1
Y1 - 2019/5/1
N2 - This paper presents the design of a soft ankle-foot orthosis (AFO) exosuit to aid natural gait restoration for individuals suffering from foot drop. The sock-like AFO is comprised of soft actuators made from fabric-based, thermally-bonded nylon and designed to be worn over the users shoes. The system assists dorsiflexion during swing phase of the gait cycle utilizing a contracting soft actuator, and provides ankle joint proprioception during stance with a variable stiffness soft actuator. A computational model is developed using finite element analysis to optimize the performance characteristics of the fabric actuators prior to fabrication, maximize contraction, and minimize overall volume. The dorsiflexion actuator is able to achieve a linear tensile force of 197 N at 200 kPa. The variable stiffness actuator generates up to 1. 2 Nm of torque at the same pressure. The computational model and soft AFO are experimentally validated and with a healthy participant through kinematic and electromyography studies. When active the AFO is capable of reducing by 13.3% the activity of the muscle responsible for ankle dorsiflexion during the swing phase.
AB - This paper presents the design of a soft ankle-foot orthosis (AFO) exosuit to aid natural gait restoration for individuals suffering from foot drop. The sock-like AFO is comprised of soft actuators made from fabric-based, thermally-bonded nylon and designed to be worn over the users shoes. The system assists dorsiflexion during swing phase of the gait cycle utilizing a contracting soft actuator, and provides ankle joint proprioception during stance with a variable stiffness soft actuator. A computational model is developed using finite element analysis to optimize the performance characteristics of the fabric actuators prior to fabrication, maximize contraction, and minimize overall volume. The dorsiflexion actuator is able to achieve a linear tensile force of 197 N at 200 kPa. The variable stiffness actuator generates up to 1. 2 Nm of torque at the same pressure. The computational model and soft AFO are experimentally validated and with a healthy participant through kinematic and electromyography studies. When active the AFO is capable of reducing by 13.3% the activity of the muscle responsible for ankle dorsiflexion during the swing phase.
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U2 - 10.1109/ICRA.2019.8794005
DO - 10.1109/ICRA.2019.8794005
M3 - Conference contribution
AN - SCOPUS:85071445928
T3 - Proceedings - IEEE International Conference on Robotics and Automation
SP - 8436
EP - 8442
BT - 2019 International Conference on Robotics and Automation, ICRA 2019
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2019 International Conference on Robotics and Automation, ICRA 2019
Y2 - 20 May 2019 through 24 May 2019
ER -