520 research outputs found
Design and Evaluation of the LOPES Exoskeleton Robot for Interactive Gait Rehabilitation
This paper introduces a newly developed gait rehabilitation device. The device, called LOPES, combines a freely translatable and 2-D-actuated pelvis segment with a leg exoskeleton containing three actuated rotational joints: two at the hip and one at the knee. The joints are impedance controlled to allow bidirectional mechanical interaction between the robot and the training subject. Evaluation measurements show that the device allows both a "pa- tient-in-charge" and "robot-in-charge" mode, in which the robot is controlled either to follow or to guide a patient, respectively. Electromyography (EMG) measurements (one subject) on eight important leg muscles, show that free walking in the device strongly resembles free treadmill walking; an indication that the device can offer task-specific gait training. The possibilities and limitations to using the device as gait measurement tool are also shown at the moment position measurements are not accurate enough for inverse-dynamical gait analysis
Robotic design and modelling of medical lower extremity exoskeletons
This study aims to explain the development of the robotic Lower Extremity Exoskeleton (LEE) systems between 1960
and 2019 in chronological order. The scans performed in the exoskeleton systemâs design have shown that a modeling
program, such as AnyBody, and OpenSim, should be used first to observe the design and software animation, followed
by the mechanical development of the system using sensors and motors. Also, the use of OpenSim and AnyBody
musculoskeletal system software has been proven to play an essential role in designing the human-exoskeleton by
eliminating the high costs and risks of the mechanical designs. Furthermore, these modeling systems can enable rapid
optimization of the LEE design by detecting the forces and torques falling on the human muscles
Electromechanical and robotic devices for gait and balance rehabilitation of children with neurological disability: a systematic review
In the last two decades, a growing interest has been focused on gait and balance robot-assisted rehabilitation in children with neurological disabilities. Robotic devices allow the implementation of intensive, task-specific training fostering functional recovery and neuroplasticity phenomena. However, limited attention has been paid to the protocols used in this research framework. This systematic review aims to provide an overview of the existing literature on robotic systems for the rehabilitation of gait and balance in children with neurological disabilities and their rehabilitation applications. The literature search was carried out independently and synchronously by three authors on the following databases: MEDLINE, Cochrane Library, PeDro, Institute of Electrical and Electronics Engineers, ScienceDirect, and Google Scholar. The data collected included three subsections referring to clinical, technical, and regulatory aspects. Thirty-one articles out of 81 found on the primary literature search were included in the systematic review. Most studies involved children with cerebral palsy. Only one-third of the studies were randomized controlled trials. Overall, 17 devices (nine end-effector systems and eight exoskeletons) were investigated, among which only 4 (24%) were bore the CE mark. Studies differ on rehabilitation protocols duration, intensity, and outcome measures. Future research should improve both rehabilitation protocols\u2019 and devices\u2019 descriptions
Adapted assistance and resistance training with a knee exoskeleton after stroke
Studies on robotic interventions for gait rehabilitation after stroke require: (i) rigorous performance evidence; (ii) systematic procedures to tune the control parameters; and (iii) combination of control modes. In this study, we investigated how stroke individuals responded to training for two weeks with a knee exoskeleton (ABLE-KS) using both Assistance and Resistance training modes together with auditory feedback to train peak knee flexion angle. During the training, the torque provided by the ABLE-KS and the biofeedback were systematically adapted based on the subjectâs performance and perceived exertion level. We carried out a comprehensive experimental analysis that evaluated a wide range of biomechanical metrics, together with usability and usersâ perception metrics. We found significant improvements in peak knee flexion ( p=0.0016 ), minimum knee angle during stance ( p=0.0053 ), paretic single support time ( p=0.0087 ) and gait endurance ( p=0.022 ) when walking without the exoskeleton after the two weeks of training. Participants significantly ( p<0.00025 ) improved the knee angle during the stance and swing phases when walking with the exoskeleton powered in the high Assistance mode in comparison to the No Exo and the Unpowered conditions. No clinically relevant differences were found between Assistance and Resistance training sessions. Participants improved their performance with the exoskeleton (24-55 %) for the peak knee flexion angle throughout the training sessions. Moreover, participants showed a high level of acceptability of the ABLE-KS (QUEST 2.0 score: 4.5 ± 0.3 out of 5). Our preliminary findings suggest that the proposed training approach can produce similar or larger improvements in post-stroke individuals than other studies with knee exoskeletons that used higher training intensities.This work was supported in part by the Agency for Management of University and Research Grants (AGAUR) along with the Secretariat of Universities and Research of the Catalan Ministry of Research and Universities and the European Social Fund (ESF) under Grant 2020 FI_B 00331, in part by the Spanish Ministry of Science and Innovation (MCI)âAgencia Estatal de InvestigaciĂłn (AEI) under Grant PTQ2018-010227, in part by âLa Caixaâ Foundation under Grant LCF/TR/CC20/52480002, and in part by the Eurostars-3 Joint Program with co-financing from CDTI and the European Unionâs Horizon Europe Research and Innovation Framework Program under Eureka Application Number 1789 under Grant CIIP-20221022Peer ReviewedPostprint (published version
Feedback Control of an Exoskeleton for Paraplegics: Toward Robustly Stable Hands-free Dynamic Walking
This manuscript presents control of a high-DOF fully actuated lower-limb
exoskeleton for paraplegic individuals. The key novelty is the ability for the
user to walk without the use of crutches or other external means of
stabilization. We harness the power of modern optimization techniques and
supervised machine learning to develop a smooth feedback control policy that
provides robust velocity regulation and perturbation rejection. Preliminary
evaluation of the stability and robustness of the proposed approach is
demonstrated through the Gazebo simulation environment. In addition,
preliminary experimental results with (complete) paraplegic individuals are
included for the previous version of the controller.Comment: Submitted to IEEE Control System Magazine. This version addresses
reviewers' concerns about the robustness of the algorithm and the motivation
for using such exoskeleton
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