{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:05:35Z","timestamp":1787029535959,"version":"build-2736575974"},"reference-count":22,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2014,8,7]],"date-time":"2014-08-07T00:00:00Z","timestamp":1407369600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"BMBF","doi-asserted-by":"publisher","award":["13EZ1011"],"award-info":[{"award-number":["13EZ1011"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Implantable assembly components that are biocompatible and highly miniaturized are an important objective for hearing aid development. We introduce a mechanical transducer, which could be suitable as part of a prospective fully-implantable hearing aid. The transducer comprises a sensor and an actuator unit in one housing, located in the joint gap between the middle ear ossicles, the incus and stapes. The setup offers the advantage of a minimally invasive and reversible surgical solution. However, feedback between actuator and sensor due to mechanical coupling limits the available stable gain. We show that the system can be stabilized by digital control algorithms. The transducer is tested both in a finite elements method simulation of the middle ear and a physical model of a human middle ear. First, we characterize the sensor and actuator elements separately. Then, the maximum stable gain (MSG) of the whole transducer is experimentally determined in the middle ear model. With digital feedback control (using a least mean squares algorithm) in place, the total signal gain is greater than 30 dB for frequencies of 1 kHz and above. This shows the potential of the transducer as a high frequency hearing aid.<\/jats:p>","DOI":"10.3390\/s140814356","type":"journal-article","created":{"date-parts":[[2014,8,7]],"date-time":"2014-08-07T10:23:22Z","timestamp":1407407002000},"page":"14356-14374","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Examination of a Mechanical Amplifier in the Incudostapedial Joint Gap: FEM Simulation and Physical Model"],"prefix":"10.3390","volume":"14","author":[{"given":"Martin","family":"Koch","sequence":"first","affiliation":[{"name":"Clinic of Otorhinolaryngology, Department of Medicine, Technische Universit\u00e4t Dresden, Universit\u00e4tsklinik Carl Gustav Carus, Fetscherstra\u00dfe 74, 01307 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Till","family":"E\u00dfinger","sequence":"additional","affiliation":[{"name":"Clinic of Otorhinolaryngology, Department of Medicine, Technische Universit\u00e4t Dresden, Universit\u00e4tsklinik Carl Gustav Carus, Fetscherstra\u00dfe 74, 01307 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Bornitz","sequence":"additional","affiliation":[{"name":"Clinic of Otorhinolaryngology, Department of Medicine, Technische Universit\u00e4t Dresden, Universit\u00e4tsklinik Carl Gustav Carus, Fetscherstra\u00dfe 74, 01307 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Zahnert","sequence":"additional","affiliation":[{"name":"Clinic of Otorhinolaryngology, Department of Medicine, Technische Universit\u00e4t Dresden, Universit\u00e4tsklinik Carl Gustav Carus, Fetscherstra\u00dfe 74, 01307 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,8,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1177\/1084713809346262","article-title":"Middle ear implantable hearing devices: An overview","volume":"13","author":"Haynes","year":"2009","journal-title":"Trends Amplif"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1586\/erd.11.18","article-title":"The role of active middle-ear implants in the rehabilitation of hearing loss","volume":"8","author":"Green","year":"2011","journal-title":"Expert Rev. Med. Devices"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1007\/s00106-008-1852-5","article-title":"Fully implantable hearing systems","volume":"57","author":"Maurer","year":"2009","journal-title":"HNO"},{"key":"ref_4","unstructured":"Fisch, U., and May, J. (1994). Tympanoplasty, Mastoidectomy and Stapes Surgery, Georg Thieme."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.heares.2010.02.007","article-title":"Evaluation of implantable actuators by means of a middle ear simulation model","volume":"263","author":"Bornitz","year":"2010","journal-title":"Hear. Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1177\/000348949510400411","article-title":"Measurements of the stapes superstructure","volume":"104","author":"aWengen","year":"1995","journal-title":"Ann. Otol. Rhinol. Laryngol"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1097\/00129492-200405000-00021","article-title":"Clinical, experimental, and theoretical investigations of the effect of superior semicircular canal dehiscence on hearing mechanisms","volume":"25","author":"Rosowski","year":"2004","journal-title":"Otol. Neurotol"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1055\/s-2006-945076","article-title":"A new model for training in tympanoplasty","volume":"86","author":"Hofmann","year":"2007","journal-title":"Laryngo-Rhino-Otologie"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Essinger, T., and Hoffmann, R. (2014, January 1\u20133). Feedback suppression in a mechanically coupled, short signal path sensor-actuator system for use as a hearing implant. Berlin, Germany.","DOI":"10.1109\/TSP.2015.7296394"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"288","DOI":"10.1109\/JPROC.2010.2090998","article-title":"Fifty years of acoustic feedback control: State of the art and future challenges","volume":"99","author":"Moonen","year":"2011","journal-title":"Proc. IEEE"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1415","DOI":"10.1109\/5.58323","article-title":"30 Years of adaptive neural networks: Perceptron, madaline, and backpropagation","volume":"78","author":"Widrow","year":"1990","journal-title":"Proc. IEEE"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1159\/000101474","article-title":"Testing a method for quantifying the output of implantable middle ear hearing devices","volume":"12","author":"Rosowski","year":"2007","journal-title":"Audiol. Neurootol"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1159\/000013835","article-title":"Modelling of components of the human middle ear and simulation of their dynamic behavior","volume":"4","author":"Beer","year":"1999","journal-title":"Audiol. Neuro-Otol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/S0378-5955(00)00177-5","article-title":"Acoustic responses of the human middle ear","volume":"150","author":"Voss","year":"2000","journal-title":"Hear. Res."},{"key":"ref_15","first-page":"83","article-title":"Vorhersage der Empfindlichkeit Eines Implantierten Membransensors fur Cochlea-Implantate in der Gehorknochelchenkette","volume":"Volume 14","author":"Fussel","year":"2012","journal-title":"Dresdner Beitrage zur Medizintechnik, 4. Dresdner Medizintechnik Symposium"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.heares.2012.12.001","article-title":"Influence of the middle ear anatomy on the performance of a membrane sensor in the incudostapedial joint gap","volume":"301","author":"Koch","year":"2013","journal-title":"Hear. Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1159\/000069475","article-title":"Three-dimensional stapes footplate motion in human temporal bones","volume":"8","author":"Hato","year":"2003","journal-title":"Audiol. Neurootol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1016\/j.heares.2011.11.008","article-title":"Contribution of complex stapes motion to cochlea activation","volume":"284","author":"Eiber","year":"2012","journal-title":"Hear. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1245","DOI":"10.1121\/1.3458850","article-title":"Evaluation of feedback reduction techniques in hearing aids based on physical performance measures","volume":"128\/3","author":"Spriet","year":"2010","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1007\/s00106-004-1058-4","article-title":"Horgerate im Alter","volume":"52","author":"Hesse","year":"2004","journal-title":"HNO"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Lehnhardt, E., and Laszig, R. (2009). Praxis der Audiometrie, Georg Thieme Verlag KG. [9th ed.].","DOI":"10.1055\/b-002-44901"},{"key":"ref_22","first-page":"272","article-title":"An evaluation of several rationales for selecting hearing aid gain","volume":"51","author":"Humes","year":"1986","journal-title":"J. Speech Hear. Res."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/8\/14356\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:14:31Z","timestamp":1760217271000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/8\/14356"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,8,7]]},"references-count":22,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2014,8]]}},"alternative-id":["s140814356"],"URL":"https:\/\/doi.org\/10.3390\/s140814356","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,8,7]]}}}