{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T08:03:44Z","timestamp":1789718624633,"version":"4.0.1"},"reference-count":49,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,12]],"date-time":"2022-02-12T00:00:00Z","timestamp":1644624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000738","name":"United States Department of Veterans Affairs","doi-asserted-by":"publisher","award":["1I01RX002275-01"],"award-info":[{"award-number":["1I01RX002275-01"]}],"id":[{"id":"10.13039\/100000738","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["CPS1739800"],"award-info":[{"award-number":["CPS1739800"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>(1) Background: An iterative learning control (ILC) strategy was developed for a \u201cMuscle First\u201d Motor-Assisted Hybrid Neuroprosthesis (MAHNP). The MAHNP combines a backdrivable exoskeletal brace with neural stimulation technology to enable persons with paraplegia due to spinal cord injury (SCI) to execute ambulatory motions and walk upright. (2) Methods: The ILC strategy was developed to swing the legs in a biologically inspired ballistic fashion. It maximizes muscular recruitment and activates the motorized exoskeletal bracing to assist the motion as needed. The control algorithm was tested using an anatomically realistic three-dimensional musculoskeletal model of the lower leg and pelvis suitably modified to account for exoskeletal inertia. The model was developed and tested with the OpenSim biomechanical modeling suite. (3) Results: Preliminary data demonstrate the efficacy of the controller in swing-leg simulations and its ability to learn to balance muscular and motor contributions to improve performance and accomplish consistent stepping. In particular, the controller took 15 iterations to achieve the desired outcome with 0.3% error.<\/jats:p>","DOI":"10.3390\/bioengineering9020071","type":"journal-article","created":{"date-parts":[[2022,2,13]],"date-time":"2022-02-13T20:32:30Z","timestamp":1644784350000},"page":"71","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Biologically Inspired Optimal Terminal Iterative Learning Control for the Swing Phase of Gait in a Hybrid Neuroprosthesis: A Modeling Study"],"prefix":"10.3390","volume":"9","author":[{"given":"Nathaniel S.","family":"Makowski","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, MetroHealth System, Cleveland, OH 44109, USA"},{"name":"APT Center, Louis Stokes VA Medical Center, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9896-2563","authenticated-orcid":false,"given":"Marshaun N.","family":"Fitzpatrick","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0984-5803","authenticated-orcid":false,"given":"Ronald J.","family":"Triolo","sequence":"additional","affiliation":[{"name":"APT Center, Louis Stokes VA Medical Center, Cleveland, OH 44106, USA"},{"name":"Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan-David","family":"Reyes","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roger D.","family":"Quinn","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5737-1708","authenticated-orcid":false,"given":"Musa","family":"Audu","sequence":"additional","affiliation":[{"name":"APT Center, Louis Stokes VA Medical Center, Cleveland, OH 44106, USA"},{"name":"Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1371","DOI":"10.1089\/neu.2004.21.1371","article-title":"Targeting Recovery: Priorities of the Spinal Cord-Injured Population","volume":"21","author":"Anderson","year":"2004","journal-title":"J. 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