Mechanism that compensates for misalignments in joint-exoskeleton movements, reducing risk of injury.

Powered knee exoskeletons provide power and torque at the joint level. However, if the user’s joint is not perfectly aligned with the exoskeleton, the exoskeleton’s assistance may result in both dangerous and repetitive torques being transferred to the user’s limb, raising the risk for injury.

University of Utah researchers have developed and tested a self-aligning mechanism that compensates for joint-exoskeleton misalignment. The mechanism uses passive degree of freedom and elastic elements to align the user’s limb with the exoskeleton and has effectively compensated for misalignments during tests with four healthy subjects. Additionally, the tests demonstrated sufficient compensation at varying levels of alignment and exoskeleton-powered assistance, illustrating the mechanism’s efficacy compensating for misalignments during tasks requiring high assistive torque.

Pre-Clinical Validation

• Aligns automatically to joint motion.
• Eliminates undesired force loads on user joints.
• Offers easy assembly and set-up.

Sarkisian, S. V., Ishmael, M. K., Hunt, G. R., & Lenzi, T. (2020). Design, Development, and Validation of a Self-Aligning Mechanism for High-Torque Powered Knee Exoskeletons. IEEE Transactions on Medical Robotics and Bionics, 2(2), 248-259. doi: 10.1109/tmrb.2020.2981951

For a video demonstration: https://www.youtube.com/watch?v=y6ngETuMUkA

Huy Tran
(801) 581-7792
huy.tran@utah.edu