title: Wireless charing pillow for a fully implantable hearing aid: Design of a circular array coil based on finite element analysis for reducing magnetic weak zones.
abstract: Many types of fully implantable hearing aids have been developed. Most of these devices are implanted behind the ear. To maintain the implanted device for a long period of time, a rechargeable battery and wireless power transmission are used. Because inductive coupling is the most renowned method for wireless power transmission, many types of fully implantable hearing aids are transcutaneously powered using inductively coupled coils. Some patients with an implantable hearing aid require a method for conveniently charging their hearing aid while they are resting or sleeping. To address this need, a wireless charging pillow has been developed that employs a circular array coil as one of its primary parts. In this device, all primary coils are simultaneously driven to maintain an effective charging area regardless of head motion. In this case, however, there may be a magnetic weak zone that cannot be charged at the specific secondary coil's location on the array coil. In this study, assuming that a maximum charging distance is 4 cm, a circular array coil-serving as a primary part of the charging pillow-was designed using finite element analysis. Based on experimental results, the proposed device can charge an implantable hearing aid without a magnetic weak zone within 4 cm of the perpendicular distance between the primary and secondary coils.
authors.affiliation: Graduate School of Electronics Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701, Korea.
authors.forename: Hyung-Gyu
authors.initials: HG
authors.lastname: Lim
authors.affiliation: Department of Medical and Biological Engineering, Graduate School, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, Daegu 700-422, Korea.
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Graduate School of Electronics Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701, Korea.
authors.forename: Dong Ho
authors.initials: DH
authors.lastname: Shin
authors.affiliation: Graduate School of Electronics Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701, Korea.
authors.forename: Seong Tak
authors.initials: ST
authors.lastname: Woo
authors.affiliation: Department of Biomedical Engineering, Kyungpook National University Hospital, 130 Dongdeok-ro, Jung-gu, Daegu 700-721, Korea.
authors.forename: Ki Woong
authors.initials: KW
authors.lastname: Seong
authors.affiliation: Department of Biomedical Engineering, Kyungpook National University Hospital, 130 Dongdeok-ro, Jung-gu, Daegu 700-721, Korea.
authors.forename: Jyung Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Biomedical Engineering, School of Medicine, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, Daegu 700-422, Korea.
authors.forename: Myoung Nam
authors.initials: MN
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, School of Medicine, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 704-701, Korea.
authors.forename: Qun
authors.initials: Q
authors.lastname: Wei
authors.affiliation: Graduate School of Electronics Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701, Korea.
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Cho
mesh_terms: D001512:Bedding and Linens; D001513:Beds; D017076:Computer-Aided Design; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020342:Finite Element Analysis; D006310:Hearing Aids; D060526:Magnetic Fields; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D019736:Prostheses and Implants; D059015:Wireless Technology / Q000295:instrumentation*
keywords: Wireless charging pillow; circular array coil; fully implantable hearing aid; inductive coupling; magnetic weak zone