{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T18:30:25Z","timestamp":1773167425501,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,5]],"date-time":"2023-02-05T00:00:00Z","timestamp":1675555200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/04077\/2020"],"award-info":[{"award-number":["UIDB\/04077\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/00319\/2020"],"award-info":[{"award-number":["UIDB\/00319\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/121994\/2016"],"award-info":[{"award-number":["SFRH\/BD\/121994\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Machines"],"abstract":"<jats:p>Regardless of the type of sport, coaches must perform the difficult task of evaluating the performance of athletes. In some cases, this task is aided using technology which provides tools for this purpose. When the sport considered is taekwondo this scenario does not apply as the athlete evaluation methods used are mostly manual. Thus, the project presented in this paper has the main objective to develop a system that can be used as a tool to evaluate the performance of taekwondo athletes in real time, with special attention to the low cost of implementation and ease of use. With the intention of meeting these requirements, the developed system comprises a 3D camera with a depth sensor (Orbbec Astra), Inertial Measurement Units (IMUs) with accelerometer and gyroscope, a computer and specific software developed for this purpose. This system allows the collection of data from the athletes\u2019 movements necessary for the creation of a dataset that is then analyzed and interpretated. The system permits the user to obtain real-time information about the speed, acceleration, and strength of the athlete\u2019s limbs during training as well as the identification of some movements and their accounting. To achieve this functionality, deep-learning architecture models were used, more specifically long short-term memory (LSTM). The intention is to provide a new training methodology through faster feedback, so that a faster evolution of the athlete\u2019s performance is possible, contributing to the technological development of the assessment practices used in taekwondo.<\/jats:p>","DOI":"10.3390\/machines11020234","type":"journal-article","created":{"date-parts":[[2023,2,6]],"date-time":"2023-02-06T02:29:23Z","timestamp":1675650563000},"page":"234","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Cyber-Physical System for Evaluation of Taekwondo Athletes: An Initial Project Description"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6170-1626","authenticated-orcid":false,"given":"Pedro","family":"Cunha","sequence":"first","affiliation":[{"name":"Algoritmi Research Centre, University of Minho, 4800-058 Guimaraes, Portugal"},{"name":"2Ai, School of Technology, Polytechnic Institute of C\u00e1vado and Ave, 4750-810 Barcelos, Portugal"}]},{"given":"Paulo","family":"Barbosa","sequence":"additional","affiliation":[{"name":"2Ai, School of Technology, Polytechnic Institute of C\u00e1vado and Ave, 4750-810 Barcelos, Portugal"}]},{"given":"F\u00e1bio","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Minho, 4800-058 Guimaraes, Portugal"}]},{"given":"T\u00e2nia","family":"Silva","sequence":"additional","affiliation":[{"name":"Research Institute for Design, Media and Culture, School of Design, Polytechnic Institute of C\u00e1vado and Ave., 4750-810 Barcelos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5228-5453","authenticated-orcid":false,"given":"Nuno","family":"Martins","sequence":"additional","affiliation":[{"name":"Research Institute for Design, Media and Culture, School of Design, Polytechnic Institute of C\u00e1vado and Ave., 4750-810 Barcelos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4438-6713","authenticated-orcid":false,"given":"Filomena","family":"Soares","sequence":"additional","affiliation":[{"name":"Algoritmi Research Centre, University of Minho, 4800-058 Guimaraes, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4658-5844","authenticated-orcid":false,"given":"V\u00edtor","family":"Carvalho","sequence":"additional","affiliation":[{"name":"Algoritmi Research Centre, University of Minho, 4800-058 Guimaraes, Portugal"},{"name":"2Ai, School of Technology, Polytechnic Institute of C\u00e1vado and Ave, 4750-810 Barcelos, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,5]]},"reference":[{"key":"ref_1","unstructured":"(2022, November 23). 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