{"paper":{"title":"Dynamics Computation of Soft-Rigid Hybrid-Link System and Its Application to Motion Analysis of an Athlete Wearing Sport Prosthesis","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"A soft-rigid hybrid-link model enables inverse kinematics and dynamics computation for athletes wearing flexible prostheses, with 12% error reported on ground-reaction-force estimation in a human-subject trial.","cross_cats":[],"primary_cat":"cs.RO","authors_text":"Ko Yamamoto, Sunghee Kim, Taiki Ishigaki, Yuta Shimane","submitted_at":"2026-05-13T08:49:44Z","abstract_excerpt":"This paper presents a motion analysis framework for an athlete wearing sport-specific flexible prosthesis based on the soft-rigid hybrid-link system. Such a motion analysis is a challenging problem because we need to consider the interaction force between the rigid human skeleton system and a flexible prosthesis. However, most of human musculoskeletal models are based on the computation framework of a rigid-body multi-link system. Recently in soft robotics research field, fast and efficient modeling methods were developed for a flexible rod deformation, which allows us to build a hybrid-link s"},"claims":{"count":3,"items":[{"kind":"strongest_claim","text":"Through a human subject experiment, we show that the inverse dynamics achieved approximately 12% error on the ground reaction force estimation. Furthermore, we provide the muscle force estimation considering muscle amputation and interaction force with the prosthesis leg deformation.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The hybrid-link formulation accurately captures the interaction force between the rigid human skeleton and the flexible prosthesis without requiring additional parameters or post-hoc tuning that would invalidate the inverse-dynamics results.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"A soft-rigid hybrid-link model enables inverse kinematics and dynamics computation for athletes wearing flexible prostheses, with 12% error reported on ground-reaction-force estimation in a human-subject trial.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"}],"snapshot_sha256":"9cb36ea99c5023550459bf7bb4ded397753d07971946e613c21638893f40e590"},"source":{"id":"2605.13192","kind":"arxiv","version":1},"verdict":{"id":"3ab3dd92-58be-4931-ae63-91b697a816bc","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T18:16:42.991145Z","strongest_claim":"Through a human subject experiment, we show that the inverse dynamics achieved approximately 12% error on the ground reaction force estimation. Furthermore, we provide the muscle force estimation considering muscle amputation and interaction force with the prosthesis leg deformation.","one_line_summary":"A soft-rigid hybrid-link model enables inverse kinematics and dynamics computation for athletes wearing flexible prostheses, with 12% error reported on ground-reaction-force estimation in a human-subject trial.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The hybrid-link formulation accurately captures the interaction force between the rigid human skeleton and the flexible prosthesis without requiring additional parameters or post-hoc tuning that would invalidate the inverse-dynamics results.","pith_extraction_headline":""},"references":{"count":26,"sample":[{"doi":"","year":2068,"title":"The fastest sprinter in 2068 has an artificial limb? ; 2015","work_id":"c840effa-0b86-444d-ac25-6dae97bc9c0e","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2005,"title":"Somatosensory computation for man-machine interface from motion-capture data and musculoskeletal human model","work_id":"f4e6d8c7-de38-4271-bc77-9a859d0f9324","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2007,"title":"Opensim: open-source software to create and analyze dynamic simulations of movement","work_id":"1a2381d8-936f-4670-addc-161ecc864230","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2016,"title":"A prosthesis-specific multi-link segment model of lower- limb amputee sprinting","work_id":"72f89cd8-dc33-4dde-aa84-4ff495d322de","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2018,"title":"Inverse optimal control based enhancement of sprinting motion analysis with and without running-specific prostheses","work_id":"d94a1224-73c9-4dce-9632-2fa6fb4aca83","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":26,"snapshot_sha256":"459956fed37844977ea47c32da8d853bd80f8f52be5bcf89229b8d8e17464acb","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}