Evidence map›Paper›PMID 34805288›Full record

ArticleFrontiers in robotics and AI2021

Shared Control of a Powered Exoskeleton and Functional Electrical Stimulation Using Iterative Learning.

Vahidreza Molazadeh, Qiang Zhang, Xuefeng Bao, Brad E Dicianno, Nitin Sharma

Open access · goldAbstract read
In one paragraph

Article in Frontiers in robotics and AI, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
0.8field-weighted citation impact, top 30% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 19 citations in OpenAlex.

  1. Article
  2. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 3 institutions in 1 country.

Vahidreza MolazadehDepartment of Mechanical Engineering and Material Science, University of Pittsburgh, Pittsburgh, PA, United States.
Qiang ZhangNeuromuscular Control and Robotics Lab, Joint Department of Biomedical Engineering, North Carolina State University and the University of North Carolina Chapel-Hill, Raleigh, NC, United States.
Xuefeng BaoDepartment of Biomedical Engineering at University of Wisconsin-Milwaukee, Milwaukee, WI, United States.
Brad E DiciannoDepartment of Physical Medicine and Rehabilitation, School of Medicine and Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.
Nitin SharmaNeuromuscular Control and Robotics Lab, Joint Department of Biomedical Engineering, North Carolina State University and the University of North Carolina Chapel-Hill, Raleigh, NC, United States.
North Carolina State University · USUniversity of Pittsburgh · USUniversity of Wisconsin–Milwaukee · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

A hybrid exoskeleton comprising a powered exoskeleton and functional electrical stimulation (FES) is a promising technology for restoration of standing and walking functions after a neurological injury. Its shared control remains challenging due to the need to optimally distribute joint torques among FES and the powered exoskeleton while compensating for the FES-induced muscle fatigue and ensuring performance despite highly nonlinear and uncertain skeletal muscle behavior. This study develops a bi-level hierarchical control design for shared control of a powered exoskeleton and FES to overcome these challenges. A higher-level neural network-based iterative learning controller (NNILC) is derived to generate torques needed to drive the hybrid system. Then, a low-level model predictive control (MPC)-based allocation strategy optimally distributes the torque contributions between FES and the exoskeleton's knee motors based on the muscle fatigue and recovery characteristics of a participant's quadriceps muscles. A Lyapunov-like stability analysis proves global asymptotic tracking of state-dependent desired joint trajectories. The experimental results on four non-disabled participants validate the effectiveness of the proposed NNILC-MPC framework. The root mean square error (RMSE) of the knee joint and the hip joint was reduced by 71.96 and 74.57%, respectively, in the fourth iteration compared to the RMSE in the 1st sit-to-stand iteration.

Indexed as

exoskeletonfunctional electrical stimulation (FES)iterative learningshared controlwearable robot

Identifiers

PMID34805288
PMCPMC8595125
OpenAlexW3209326698

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.