{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T15:06:17Z","timestamp":1775228777030,"version":"3.50.1"},"reference-count":19,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,25]],"date-time":"2021-12-25T00:00:00Z","timestamp":1640390400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Custom-made dynamometry was shown to objectively analyze human muscle strength around the ankle joint with accuracy, easy portability and low costs. This paper describes the full method of calibration and measurement setup and the measurement procedure when capturing ankle torque for establishing reliability of a portable custom-built electronic dynamometer. After considering the load cell offset voltage, the pivotal position was determined, and calibration with loads followed. Linear regression was used for calculating the proportionality constant between torque and measured voltage. Digital means were used for data collection and processing. Four healthy consenting participants were enrolled in the study. Three consecutive maximum voluntary isometric contractions of five seconds each were registered for both feet during plantar flexion\/dorsiflexion, and ankle torque was then calculated for three ankle inclinations. A calibration procedure resulted, comprising determination of the pivotal axis and pedal constant. Using the obtained data, a measurement procedure was proposed. Obtained contraction time graphs led to easier filtering of the results. When calculating the interclass correlation, the portable apparatus demonstrated to be reliable when measuring ankle torque. When a custom-made dynamometer was used for capturing ankle torque, accuracy of the method was assured by a rigorous calibration and measurement protocol elaboration.<\/jats:p>","DOI":"10.3390\/s22010135","type":"journal-article","created":{"date-parts":[[2021,12,27]],"date-time":"2021-12-27T01:06:54Z","timestamp":1640567214000},"page":"135","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Custom-Made Lower Limb Dynamometer for Assessing Ankle Joint Torque in Humans: Calibration and Measurement Procedures"],"prefix":"10.3390","volume":"22","author":[{"given":"Iulia Iovanca","family":"Dr\u0103goi","sequence":"first","affiliation":[{"name":"Department of Vascular Surgery and Reconstructive Microsurgery, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania"}]},{"given":"Florina Georgeta","family":"Popescu","sequence":"additional","affiliation":[{"name":"Discipline of Occupational Health, \u201cVictor Babe\u015f\u201d University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7267-3069","authenticated-orcid":false,"given":"Teodor","family":"Petri\u021ba","sequence":"additional","affiliation":[{"name":"Department of Communications, Politehnica University Timi\u0219oara, 2 Vasile P\u00e2rvan, 300223 Timisoara, Romania"}]},{"given":"Romulus Fabian","family":"Tatu","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics-Traumatology-Urology and Imagistics, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania"}]},{"given":"Cosmina Ioana","family":"Bondor","sequence":"additional","affiliation":[{"name":"Department of Medical Informatics and Biostatistics, University of Medicine and Pharmacy \u201cIuliu Ha\u021bieganu\u201d, 8 Victor Babe\u0219, 400000 Cluj-Napoca, Romania"}]},{"given":"Carmen","family":"Tatu","sequence":"additional","affiliation":[{"name":"Department of Functional Sciences, Physiology, Center of Immuno-Physiology and Biotechnologies, \u201cVictor Babe\u015f\u201d University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania"}]},{"given":"Frank L.","family":"Bowling","sequence":"additional","affiliation":[{"name":"Department of Vascular Surgery and Reconstructive Microsurgery, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania"},{"name":"Department of Surgery & Translational Medicine, Faculty of Medical and Human Sciences, University of Manchester, Oxford Rd., Manchester M13 9PL, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9213-4580","authenticated-orcid":false,"given":"Neil D.","family":"Reeves","sequence":"additional","affiliation":[{"name":"Research Centre for Musculoskeletal Science & Sports Medicine, Department of Life Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Oxford Rd., Manchester M1 5GD, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9214-302X","authenticated-orcid":false,"given":"Mihai","family":"Ionac","sequence":"additional","affiliation":[{"name":"Department of Vascular Surgery and Reconstructive Microsurgery, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy, 2 Eftimie Murgu Square, 300041 Timisoara, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1146\/annurev-bioeng-070909-105259","article-title":"Muscle and Joint Function in Human Locomotion","volume":"12","author":"Pandy","year":"2010","journal-title":"Annu. 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