{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T06:15:09Z","timestamp":1775196909613,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T00:00:00Z","timestamp":1774656000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>Lower-limb rehabilitation exoskeletons must balance biomechanical compatibility, structural safety, and low mass to enable practical, repeatable gait assistance. This paper proposes a planar pantograph-derived exoskeleton leg driven by a Chebyshev Lambda linkage and develops an integrated workflow from mechanism synthesis to manufacturable optimization and experimental verification. A mannequin-coupled multibody model was built in MSC ADAMS to evaluate joint kinematics, end-point (foot) trajectories, and joint reaction forces under multiple scenarios (fixed-frame, ramp, stair ascent, and inclined-plane walking). The extracted joint loads were transferred to a parametric finite element model in ANSYS Workbench 2019, where response surface surrogates and a multi-objective genetic algorithm (MOGA) were used to minimize mass under stiffness and strength constraints. For the optimized load-bearing link, the selected minimum-mass design reached a component mass of 0.542 kg while respecting the imposed structural limits, i.e., a maximum total deformation below 0.2 mm and a maximum equivalent (von Mises) stress below 50 MPa (e.g., ~0.188 mm deformation and ~39 MPa stress in the optimal candidate). A rapid prototype was manufactured by 3D printing and experimentally evaluated using CONTEMPLAS high-speed video tracking, providing measured XM(t) and YM(t) trajectories and joint-angle histories for quantitative comparison with simulations via RMSE metrics.<\/jats:p>","DOI":"10.3390\/robotics15040071","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T13:41:53Z","timestamp":1774878113000},"page":"71","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Integrated Design of a Modular Lower-Limb Rehabilitation Exoskeleton: Multibody Simulation, Load-Driven Structural Optimization, and Experimental Validation"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8844-0497","authenticated-orcid":false,"given":"Ionut","family":"Geonea","sequence":"first","affiliation":[{"name":"Department of Applied Mechanics and Civil Engineering, Faculty of Mechanics, University of Craiova, 200478 Craiova, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-6802-7476","authenticated-orcid":false,"given":"Andrei","family":"Corzanu","sequence":"additional","affiliation":[{"name":"Department of Applied Mechanics and Civil Engineering, Faculty of Mechanics, University of Craiova, 200478 Craiova, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2807-9948","authenticated-orcid":false,"given":"Cristian","family":"Copilusi","sequence":"additional","affiliation":[{"name":"Department of Applied Mechanics and Civil Engineering, Faculty of Mechanics, University of Craiova, 200478 Craiova, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8512-0156","authenticated-orcid":false,"given":"Adriana","family":"Ionescu","sequence":"additional","affiliation":[{"name":"Department of Applied Mechanics and Civil Engineering, Faculty of Mechanics, University of Craiova, 200478 Craiova, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6935-6641","authenticated-orcid":false,"given":"Daniela","family":"Tarnita","sequence":"additional","affiliation":[{"name":"Department of Applied Mechanics and Civil Engineering, Faculty of Mechanics, University of Craiova, 200478 Craiova, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Flor-Unda, O., Arcos-Reina, R., Toapanta, C., Villao, F., Bustos-Estrella, A., Suntaxi, C., and Palacios-Cabrera, H. 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