English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Powered lower limb exoskeletons are a viable solution for people with aspinal cord injury to regain mobility for their daily activities. However, thecommonly employed rigid actuation and pre-programmed trajectories increase therisk of falling in case of collisions with external objects. Compliantactuation may reduce forces during collisions, thus protecting hardware anduser. However, experimental data of collisions specific to lower limbexoskeletons are not available. In this work, we investigated how a variablestiffness actuator at the knee joint influences collision forces transmitted tothe user via the exoskeleton. In a test bench experiment, we compared threeconfigurations of an exoskeleton leg with a variable stiffness knee actuator in(i) compliant or (ii) stiff configurations, and with (iii) a rigid actuator.The peak torque observed at the pelvis was reduced from 260.2 Nm to 116.2 Nm asstiffness decreased. In addition, the mechanical impulse was reduced by afactor of three. These results indicate that compliance in the knee joint of anexoskeleton can be favorable in case of collision and should be considered whendesigning powered lower limb exoskeletons. Overall, this could decrease theeffort necessary to maintain balance after a collision and improved collisionhandling in exoskeletons could result in safer use and benefit their usefulnessin daily life.

Knee Compliance Reduces Peak Swing Phase Collision Forces in a Lower-Limb Exoskeleton Leg: A Test Bench Evaluation