{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:49:37Z","timestamp":1760233777572,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,9]],"date-time":"2021-02-09T00:00:00Z","timestamp":1612828800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Consejo Nacional de Ciencia y Tecnolog\u00eda, M\u00e9xico","award":["783323"],"award-info":[{"award-number":["783323"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, the natural frequencies (NFs) identification by finite element method (FEM) is applied to a two degrees-of-freedom (2-DOF) planar robot, and its validation through a novel experimental methodology, the Multiple Signal Classification (MUSIC) algorithm, is presented. The experimental platforms are two different 2-DOF planar robots with different materials for the links and different types of actuators. The FEM is carried out using ANSYS\u2122 software for the experiments, with vibration signal analysis by MUSIC algorithm. The advantages of the MUSIC algorithm against the commonly used fast Fourier transform (FFT) method are also presented for a synthetic signal contaminated by three different noise levels. The analytical and experimental results show that the proposed methodology identifies the NFs of a high-resolution robot even when they are very closed and when the signal is embedded in high-level noise. Furthermore, the results show that the proposed methodology can obtain a high-frequency resolution with a short sample data set. Identifying the NFs of robots is useful for avoiding such frequencies in the path planning and in the selection of controller gains that establish the bandwidth.<\/jats:p>","DOI":"10.3390\/s21041209","type":"journal-article","created":{"date-parts":[[2021,2,10]],"date-time":"2021-02-10T04:33:46Z","timestamp":1612931626000},"page":"1209","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Natural Frequencies Identification by FEM Applied to a 2-DOF Planar Robot and Its Validation Using MUSIC Algorithm"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6119-9146","authenticated-orcid":false,"given":"Salvador","family":"Mart\u00ednez-Cruz","sequence":"first","affiliation":[{"name":"Facultad de Ingenier\u00eda, Campus San Juan del R\u00edo, Universidad Aut\u00f3noma de Quer\u00e9taro, San Juan del R\u00edo, Quer\u00e9taro 76807, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9559-0220","authenticated-orcid":false,"given":"Juan P.","family":"Am\u00e9zquita-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Campus San Juan del R\u00edo, Universidad Aut\u00f3noma de Quer\u00e9taro, San Juan del R\u00edo, Quer\u00e9taro 76807, Mexico"}]},{"given":"Gerardo I.","family":"P\u00e9rez-Soto","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Santiago de Quer\u00e9taro, Quer\u00e9taro 76010, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9141-3454","authenticated-orcid":false,"given":"Jes\u00fas R.","family":"Rivera-Guill\u00e9n","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Campus San Juan del R\u00edo, Universidad Aut\u00f3noma de Quer\u00e9taro, San Juan del R\u00edo, Quer\u00e9taro 76807, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6483-0543","authenticated-orcid":false,"given":"Luis A.","family":"Morales-Hern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Campus San Juan del R\u00edo, Universidad Aut\u00f3noma de Quer\u00e9taro, San Juan del R\u00edo, Quer\u00e9taro 76807, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6968-9772","authenticated-orcid":false,"given":"Karla A.","family":"Camarillo-G\u00f3mez","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico\/Instituto Tecnol\u00f3gico de Celaya, Celaya, Guanajuato 38010, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1016\/j.bspc.2019.02.022","article-title":"Toward a bio-inspired rehabilitation aid: sEMG-CPG approach for online generation of jaw trajectories for a chewing robot","volume":"51","author":"Kalani","year":"2019","journal-title":"Biomed. 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