{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T21:43:22Z","timestamp":1769550202255,"version":"3.49.0"},"reference-count":33,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,10,8]],"date-time":"2023-10-08T00:00:00Z","timestamp":1696723200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["UIDB\/50022\/2020"],"award-info":[{"award-number":["UIDB\/50022\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Actuators"],"abstract":"<jats:p>Depth control is crucial for underwater vehicles, not only to perform certain tasks that require the vehicle to be still at a given depth but also because most propeller-driven vehicles waste a considerable amount of energy to counteract the passively tuned positive buoyancy. The use of a variable buoyancy system (VBS) can effectively address these items, increasing the energetic efficiency and thus mission length. Achieving accurate depth controllers is, however, a complex task, since experimental controller development in sea or even in test pools is unpractical and the use of simulation requires accurate vertical motion models whose parameters might be difficult to obtain or measure. The development of simple, yet comprehensive, dynamic models for devices incorporating VBS is therefore of upmost importance, as well as developing procedures that allow a simple determination of their parameters. This work contributes to this field by deriving a unified model for the vertical motion of a VBS actuated device, irrespective of the specific technological actuation solution employed, whether it be electromechanical or electrohydraulic. A concise analysis of the open-loop stability of the unified model is presented and a straightforward yet efficient procedure for identifying several of its parameters is introduced. This identification procedure is designed to be convenient and can be carried out in shallow waters, such as test pools, while its results are applicable to the deeper water model as well. To validate the procedure, experimental values obtained from an electromechanical VBS actuated device are used. Closed-loop control of the electromechanical VBS actuated device is conducted through simulation and experimental tests. The results confirm the effectiveness of the proposed unified model and the parameter identification methodology.<\/jats:p>","DOI":"10.3390\/act12100380","type":"journal-article","created":{"date-parts":[[2023,10,9]],"date-time":"2023-10-09T04:56:43Z","timestamp":1696827403000},"page":"380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Electrohydraulic and Electromechanical Buoyancy Change Device Unified Vertical Motion Model"],"prefix":"10.3390","volume":"12","author":[{"given":"Jo\u00e3o","family":"Falc\u00e3o Carneiro","sequence":"first","affiliation":[{"name":"INEGI, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"}]},{"given":"Jo\u00e3o Bravo","family":"Pinto","sequence":"additional","affiliation":[{"name":"Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8573-967X","authenticated-orcid":false,"given":"Fernando","family":"Gomes de Almeida","sequence":"additional","affiliation":[{"name":"INEGI, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6365-9492","authenticated-orcid":false,"given":"Nuno A.","family":"Cruz","sequence":"additional","affiliation":[{"name":"INESC TEC, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1023\/A:1008984701078","article-title":"Design and develop of an autonomous underwater vehicle: A survey","volume":"8","author":"Yuh","year":"2000","journal-title":"Auton. Robot"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"103699","DOI":"10.1016\/j.oregeorev.2020.103699","article-title":"Seabed mineral resources, an alternative for the future of renewable energy: A critical review","volume":"126","author":"Toro","year":"2020","journal-title":"Ore Geol. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.oceaneng.2019.04.011","article-title":"Advancements in the field of autonomous underwater vehicle","volume":"181","author":"Sahoo","year":"2019","journal-title":"Ocean Eng."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"eaar3449","DOI":"10.1126\/scirobotics.aar3449","article-title":"Exploration of underwater life with an acoustically controlled soft robotic fish","volume":"3","author":"Katzschmann","year":"2018","journal-title":"Sci. Robot."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Nguyen, N.-D., Choi, H.-S., Tran, N.-H., and Kim, S.-K. (2018, January 7\u20139). Development of Ray-Type Underwater Glider. Proceedings of the AETA 2017\u2014Recent Advances in Electrical Engineering and Related Sciences: Theory and Application, Ho Chi Minh, Vietnam.","DOI":"10.1007\/978-3-319-69814-4_65"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"693","DOI":"10.1016\/j.ijnaoe.2016.12.003","article-title":"Shape optimization of blended-wing-body underwater glider by using gliding range as the optimization target","volume":"9","author":"Sun","year":"2017","journal-title":"Int. J. Nav. Archit. Ocean Eng."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1016\/j.neucom.2013.12.055","article-title":"Design and construction of an autonomous underwater vehicle","volume":"142","author":"Alam","year":"2014","journal-title":"Neurocomputing"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"08PA06","DOI":"10.7567\/JJAP.57.08PA06","article-title":"Light based underwater wireless communications","volume":"57","author":"Oubei","year":"2018","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1016\/j.optcom.2018.07.029","article-title":"Performance analysis of underwater wireless optical communication systems over a wide range of optical turbulence","volume":"427","author":"Sharifzadeh","year":"2018","journal-title":"Opt. Commun."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Soomro, M., Azar, S.N., Gurbuz, O., and Onat, A. (2017, January 5\u20138). Work-in-Progress: Networked Control of Autonomous Underwater Vehicles with Acoustic and Radio Frequency Hybrid Communication. Proceedings of the 2017 IEEE Real-Time Systems Symposium (RTSS), Paris, France.","DOI":"10.1109\/RTSS.2017.00051"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1007\/s00773-017-0432-3","article-title":"The initial study of LLS-based binocular stereo-vision system on underwater 3D image reconstruction in the laboratory","volume":"22","author":"Lin","year":"2017","journal-title":"J. Mar. Sci. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Hildebrandt, M., and Kirchner, F. (2010, January 24\u201327). IMU-aided stereo visual odometry for ground-tracking AUV applications. Proceedings of the OCEANS\u201910 IEEE SYDNEY, Sydney, NSW, Australia.","DOI":"10.1109\/OCEANSSYD.2010.5603681"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Sukvichai, K., Wongsuwan, K., Kaewnark, N., and Wisanuvej, P. (2016, January 27\u201330). Implementation of visual odometry estimation for underwater robot on ROS by using RaspberryPi 2. Proceedings of the 2016 International Conference on Electronics, Information, and Communications (ICEIC), Danang, Vietnam.","DOI":"10.1109\/ELINFOCOM.2016.7563010"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Vo, T.Q., Kim, H.S., and Lee, B.R. (2010, January 27\u201330). A study on turning motion control of a 3-joint fish robot using sliding mode based controllers. Proceedings of the ICCAS 2010, Gyeonggi, Republic of Korea.","DOI":"10.1109\/ICCAS.2010.5669688"},{"key":"ref_15","unstructured":"Kato, N., Ito, Y., Kojima, J., Takagi, S., Asakawa, K., and Shirasaki, Y. (1994, January 13\u201316). Control performance of autonomous underwater vehicle \u201cAQUA EXPLORER 1000\u201d for inspection of underwater cables. Proceedings of the Proceedings of OCEANS\u201994, Brest, France."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Wang, Z., Guo, S., Shi, L., Pan, S., and He, Y. (2014, January 3\u20136). The application of PID control in motion control of the spherical amphibious robot. Proceedings of the 2014 IEEE International Conference on Mechatronics and Automation, Tianjin, China.","DOI":"10.1109\/ICMA.2014.6885992"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1016\/j.robot.2005.04.004","article-title":"A neural network adaptive controller design for free-pitch-angle diving behavior of an autonomous underwater vehicle","volume":"52","author":"Li","year":"2005","journal-title":"Robot. Auton. Syst."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Falc\u00e3o Carneiro, J., Bravo Pinto, J., Gomes de Almeida, F., and Cruz, N.A. (2022). Design and Experimental Tests of a Buoyancy Change Module for Autonomous Underwater Vehicles. Actuators, 11.","DOI":"10.3390\/act11090254"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1729881419891536","DOI":"10.1177\/1729881419891536","article-title":"Autonomous underwater vehicle depth control based on an improved active disturbance rejection controller","volume":"16","author":"Zhang","year":"2019","journal-title":"Int. J. Adv. Robot. Syst."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"414","DOI":"10.1109\/JOE.2020.3000703","article-title":"Variable Buoyancy or Propeller-Based Systems for Hovering Capable Vehicles: An Energetic Comparison","volume":"46","author":"Carneiro","year":"2020","journal-title":"IEEE J. Ocean. Eng."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/S1474-6670(17)36681-8","article-title":"Buoyancy Control for an Autonomous Underwater Vehicle","volume":"36","author":"Love","year":"2003","journal-title":"IFAC Proc. Vol."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Huang, H., Zhang, C., Ding, W., Zhu, X., Sun, G., and Wang, H. (2020). Design of the Depth Controller for a Floating Ocean Seismograph. J. Mar. Sci. Eng., 8.","DOI":"10.3390\/jmse8030166"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Qi, Y., Wu, X., Zhang, G., and Sun, Y. (2022). Energy-Saving Depth Control of an Autonomous Underwater Vehicle Using an Event-Triggered Sliding Mode Controller. J. Mar. Sci. Eng., 10.","DOI":"10.3390\/jmse10121888"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Bai, Y., Hu, R., Bi, Y., Liu, C., Zeng, Z., and Lian, L. (2022). Design and Depth Control of a Buoyancy-Driven Profiling Float. Sensors, 22.","DOI":"10.3390\/s22072505"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"114670","DOI":"10.1109\/ACCESS.2019.2935815","article-title":"Depth Control for a Deep-Sea Self-Holding Intelligent Buoy Under Ocean Current Disturbances Based on Finite-Time Boundedness Method","volume":"77","author":"Qiu","year":"2019","journal-title":"IEEE Access"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"414","DOI":"10.1109\/JOE.2018.2875576","article-title":"Theoretical and Experimental Investigations on the Design of a Hybrid Depth Controller for a Standalone Variable Buoyancy System\u2014vBuoy","volume":"45","author":"Ranganathan","year":"2018","journal-title":"IEEE J. Ocean. Eng."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"512","DOI":"10.1051\/meca\/2020037","article-title":"Design and control of a low-cost autonomous profiling float","volume":"21","author":"Mezo","year":"2020","journal-title":"Mech. Ind."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"102925","DOI":"10.1016\/j.apor.2021.102925","article-title":"Modeling, characterization and control of a piston-driven buoyancy system for a hybrid aerial underwater vehicle","volume":"120","author":"Hu","year":"2022","journal-title":"Appl. Ocean Res."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Carneiro, J.F., Pinto, J.B., Almeida, F.G.d., and Cruz, N.A. (2023). Model Identification and Control of a Buoyancy Change Device. Actuators, 12.","DOI":"10.3390\/act12040180"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Moritz, F.G. (2014). Electromechanical Motion Systems\u2014Design and Simulation, John Wiley & Sons.","DOI":"10.1002\/9781118359785"},{"key":"ref_31","unstructured":"Merritt, H. (1967). Hydraulic Control Systems, John Wiley & Sons."},{"key":"ref_32","unstructured":"Murrenhoff, H. (2016). Fundamentals of Fluid Power. Part 1: Hydraulics, IFAS Institute fur Fluidtechnische Antriebe and Steuerungen. [8th ed.]."},{"key":"ref_33","unstructured":"Ogata, K. (2009). Modern Control Engineering, Pearson. [5th ed.]."}],"container-title":["Actuators"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0825\/12\/10\/380\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:02:56Z","timestamp":1760130176000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0825\/12\/10\/380"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,10,8]]},"references-count":33,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2023,10]]}},"alternative-id":["act12100380"],"URL":"https:\/\/doi.org\/10.3390\/act12100380","relation":{},"ISSN":["2076-0825"],"issn-type":[{"value":"2076-0825","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,10,8]]}}}